Maternal, perinatal, neonatal, and postpartum outcomes following SARS-CoV-2 infection in pregnancy: A WHO multi-country prospective cohort study 

Maternal, perinatal, neonatal, and postpartum outcomes following SARS-CoV-2 infection in pregnancy: A WHO multi-country prospective cohort study | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Maternal, perinatal, neonatal, and postpartum outcomes following SARS-CoV-2 infection in pregnancy: A WHO multi-country prospective cohort study WHO COVID-19 & Pregnancy Cohort Study Group, Edna Kara, Sami L Gottlieb, and 36 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7933142/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 13 You are reading this latest preprint version Abstract Background Our aim was to determine if SARS-CoV-2 infection during pregnancy increased the risk of adverse maternal, perinatal, neonatal, or postpartum outcomes during pre-Omicron and Omicron periods. Methods We conducted a prospective cohort study across 43 health facilities, in 10 predominantly primarily low- and middle-income countries, comprising mainly maternity, public and private hospitals in rural and urban areas. A total of 16,007 pregnant women were consecutively recruited between January 2021 and October 2023 (75% in pre-Omicron period and 25% in Omicron period), followed from enrollment through delivery and to six weeks postpartum. The main outcomes are: miscarriage, haemorrhage, preeclampsia/eclampsia, hypertensive disorders of pregnancy, thromboembolic disease, preterm labour, placental abruption, near-miss at delivery, Cesarean delivery, maternal death, modified maternal morbidity and mortality index (MMMI); stillbirth, preterm birth, low birth weight, congenital anomalies, NICU admission, perinatal death, severe perinatal morbidity and mortality index (SPMMI); haemorrhage, infection, or readmission to hospital during postpartum period. Results Based on RT-PCR or antigen testing at enrolment and serial serologic testing, 2,189 participants had confirmed SARS-CoV-2 infection during pregnancy, 116 were classified as probable infection, 7,332 as possible infection, 402 participants were considered probably uninfected, 1,053 had no evidence of infection, and 4,915 had unknown infection status. During the pre-Omicron era, the risk of several outcomes was significantly higher among the infected group compared to those uninfected: emergency Cesarean delivery (RR 1.26, CI 1.03–1.53); MMMI (RR 1.27, CI 1.12–1.44), preterm birth < 37 weeks (RR 1.73, CI 1.32–2.28), < 34 weeks (RR 3.69, CI 1.92–7.09), < 32 weeks (RR 7.58, CI 2.19–26.19), NICU admission (RR 1.90, CI 1.28–2.82) and SPMMI (RR 1.76, CI 1.01–3.05). During the Omicron era, the only outcome with a significantly elevated risk was preterm birth < 34 weeks (RR 1.88, CI 1.04–3.39). Conclusions SARS-CoV-2 infection during pregnancy was associated with an increased risk of several adverse maternal, perinatal, and neonatal outcomes, particularly in the pre-Omicron era. These risks were largely attenuated during the Omicron period; however, the persistent elevated risk for preterm birth < 34 weeks gestation underscores the need for updated evidence on SARS-CoV-2 infection and pregnancy outcomes, especially in relation to emerging Omicron sub-variants. COVID-19 Omicron pregnancy complications pregnancy outcomes maternal health neonatal outcomes cohort study Figures Figure 1 Figure 2 Background Since the emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), concerns about its effects on pregnancy have been raised worldwide. Systematic reviews and meta-analyses summarizing the effect of SARS-CoV-2 infection during pregnancy have demonstrated increased risk for multiple adverse maternal and perinatal outcomes [ 1 , 2 ]. However, these meta-analyses have been limited by varying study designs, potentially inexact definitions of infection during pregnancy, and differing outcome definitions across included studies. In addition, most available data have been from earlier in the pandemic. Several studies have shown less severe maternal illness with Omicron variants, yet studies comparing pregnancy-related outcomes in infected and uninfected pregnant women during the Omicron and Omicron sub-variant era remain limited [ 3 – 5 ]. Further, most data were from high-income countries (HICs). Less is known about the impact of infection on pregnancy in low- and middle-income countries (LMICs), where differences in access to higher-level care, underlying comorbidities, and baseline rates of adverse pregnancy outcomes might modify risks [ 6 ]. Early in the COVID-19 pandemic, the World Health Organization (WHO) developed a generic protocol for a prospective cohort study among pregnant women to facilitate systematic and harmonized data collection across different settings and to minimize potential biases. The study aimed to determine if SARS-CoV-2 infection during pregnancy increases the risk of adverse maternal, perinatal, neonatal, or postpartum outcomes. The protocol was implemented in 10 diverse, primarily LMICs (Argentina, Brazil, Burkina Faso, Chile, Ghana, Kenya, Pakistan, Philippines, Spain, and Tunisia). In this article, we report the pooled results of this study during pre-Omicron and Omicron periods of SARS-CoV-2 variant predominance. Additionally, we report on factors associated with SARS-CoV-2 illness severity, including vaccination, and the association of severity with adverse outcomes among infected women. Detailed evaluation of the effects of COVID-19 vaccination on pregnancy outcomes from this study will be reported separately. Methods This prospective cohort study was conducted between January 2021 and November 2023, across 43 health facilities in the 10 countries ( Additional File 1 - Table 1 ). The study design, data collection, and reporting adhered to the STROBE (Strengthening the Reporting of Observational Studies in Epidemiology) guidelines to ensure transparency, completeness, and methodological rigor in the presentation of the research findings. The study protocol, including sample size estimation, is available online [7]. Study procedures: enrolment Pregnant or recently pregnant women (within 48 hours of delivery or end of pregnancy) attending antenatal care or other obstetric services at participating health facilities were consecutively recruited regardless of SARS-CoV-2 infection status or vaccination status. Only those unable to provide informed consent or assent or to attend follow-up visits were excluded. At enrolment, all participants had detailed assessment of demographics, past medical and obstetric history, gestational age, details of the current pregnancy including complications and comorbidities, and COVID-19 vaccination status, with review of the obstetric record up to the time of enrolment. At enrolment, all participants received virologic testing for SARS-CoV-2, either reverse transcription polymerase chain reaction (RT-PCR) or antigen testing depending on study site, regardless of symptoms, along with serologic testing for SARS-CoV-2 antibodies. Participants who had never received a COVID-19 vaccine were tested for antibodies against the spike (S) protein of SARS-CoV-2 (Wantai BioPharm SARS-CoV-2 Ab ELISA, China). Vaccinated participants underwent anti-nucleocapsid (N) protein serologic testing (BioRad Platelia SARS-CoV-2 Total Ab Assay, USA) to distinguish infection-induced (S+/N+) from vaccine-acquired antibodies (S+/N-). An exception applied to women who received inactivated whole virus vaccines, which induce production of both anti-S and anti-N antibodies. In these cases, serologic status remained unknown. COVID-19 vaccination status was confirmed using vaccination cards, medical records, or vaccination registries wherever possible. Participants were asked about COVID-19-related symptoms, diagnoses and treatments, and medical and laboratory records were reviewed for COVID-19 diagnoses during and prior to pregnancy. Study procedures: follow-up Follow-up data were collected during regular antenatal care visits, which were typically every 4–6 weeks; however, intervals varied by country. Changes in health status, pregnancy complications, COVID-19 vaccination, COVID-19-related symptoms and laboratory findings since the previous visit were recorded, along with dates. At delivery, data were also collected on mode of delivery and pregnancy outcomes. Participants presenting with signs or symptoms related to COVID-19 at any time during follow-up received RT-PCR or antigen testing. In addition, all participants who had previous negative SARS-CoV-2 serologic testing at enrolment or follow-up had repeat serologic testing at subsequent follow-up visits including delivery. Participants were followed through six weeks after delivery, and information was collected on symptoms and health outcomes of both the woman and her neonate(s). Definitions Gestational age Gestational age was estimated based on ultrasound measurement in the first trimester or on last menstrual period (LMP), where start of pregnancy (day 0) was the first day of LMP. If both measurements were available, the best obstetric estimate was used, based on the American College of Obstetricians and Gynecologists algorithm [8]. The first trimester was defined as day 1–97 of pregnancy (week 0–13), second trimester day 98–195 (week 14–27), and third trimester day 196–280+ (week 28–40+). SARS-CoV-2 infection status Women were grouped into six mutually exclusive exposure categories based on the likelihood that SARS-CoV-2 infection occurred during pregnancy: confirmed infected, probably infected, possibly infected, probably uninfected, confirmed uninfected, and unknown ( Fig. 1 ). Figure 1. Categorizations based on likelihood of SARS-CoV-2 infection during pregnancy Participants were considered to have “confirmed” SARS-CoV-2 infection if they had a positive RT-PCR or Ag test result at any time during pregnancy or seroconversion (not related to vaccination) during follow-up. Those with consistently negative virologic and serologic test results were considered “confirmed uninfected”. Since a positive serologic test might reflect infection prior to pregnancy, most women with positive serology results were categorized as “possibly” infected during pregnancy, barring clinical diagnoses during pregnancy or known infection just prior to pregnancy. Participants whose infection status during pregnancy could not be determined because of missing data or prior receipt of inactivated vaccines were classified as “unknown”. The date of infection was defined as the date of specimen collection for positive RT-PCR and antigen tests, the midpoint between negative and positive serologic specimen collection for seroconversion, and first day of symptoms for clinical diagnosis. For those with infection, information was collected on symptoms and hospitalization. “Moderate” illness was defined as presence of fever, shortness of breath, or chest pain, while COVID-19-related hospital admission was used as a proxy for “severe” infection. Having at least one symptom but none in the moderate or severe category was defined as “mild” illness. Outcomes Study outcomes are outlined in Box 1. Detailed definitions are provided in Additional File 2 - Table 2. All analyses incorporated restrictions to ensure temporal plausibility, i.e., outcomes occurring after COVID-19 test date. Table 2 Maternal, pregnancy, perinatal, neonatal and postpartum outcomes by SARS-CoV-2 infection status during pregnancy ¥ Outcome § Confirmed or probably infected £ N = 2,305 1 Confirmed or probably uninfected £ N = 1,455 1 Adjusted infected vs uninfected random-effects model RR (95% CI); p-value 2 Overall sample (Events / Total) Restricted to pre-Omicron (Events / Total) Restricted to Omicron (Events/Total) MATERNAL AND PREGNANCY OUTCOMES Miscarriage (before 22 weeks GA)* 16/401 6/212 10/189 Yes 11 (3.7) 5 (4.9) 0.71 (0.47,1.08) p = 0.1079 0.99 (0.28,3.49) p = 0.9838 0.76 (0.53,1.10) p = 0.1447 No 290 (96.4) 97 (05.1) At risk 301 102 Miscarriage (before 28 weeks GA) * 16/403 6/213 10/190 Yes 11 (3.6) 5 (4.9) 0.71 (0.47,1.07) p = 0.1049 0.98 (0.28,3.45) p = (0.9777) 0.76 (0.53,1.10) p = 0.1426 No 292 (96.4) 97 (95.1) At risk 303 102 Haemorrhage (antepartum, intrapartum, or immediately postpartum) 116/3,565 92/2,949 24/616 Yes 80 (3.6) 37 (2.7) 1.59 (0.65,3.88) p = 0.3057 2.02 (0.95,4.29) p = 0.0677 0.51 (0.23,1.11) p = 0.0894 No 2,126 (96.4) 1,339 (97.3) At risk 2,206 1,376 Preeclampsia/eclampsia 240/3,607 185/2973 55/634 Yes 156 (7.0) 84 (6.1) 1.32 (0.76,2.31) p = 0.3293 1.46 (0.78,2.74) p = 0.2338 0.93 (0.63,1.37) p = 0.7044 No 2,087 (93.0) 1,305 (93.9) At risk 2,243 1,389 Hypertensive disorders of pregnancy 327/3,608 244/2,974 83/634 Yes 218 (9.7) 109 (7.9) 1.38 (0.83,2.31) p = 0.2153 1.59 (0.94,2.68) p = 0.0830 0.93 (0.59,1.47) p = 0.7641 No 2,026 (90.3) 1,280 (92.1) At risk 2,244 1,389 Thromboembolic disease 7/3,607 7/2,973 0/634 Yes 4 (0.2) 3 (0.2) 0.85 (0.21,3.35) p = 0.8120 0.90 (0.23,3.58) p = 0.8813 — No 2,238 (99.8) 1,385 (99.8) At risk 2,242 1,388 Preterm labour 179/2,356 132/1,856 47/500 Yes 119 (7.5) 60 (7.6) 0.91 (0.68,1.22) p = 0.5259 0.80 (0.59,1.09) p = 0.1542 1.27 (0.74,2.17) p = 0.3831 No 1,459 (92.5) 731 (92.4) At risk 1,578 791 Placental abruption 17/3,607 14/2,973 3/634 Yes 10 (0.5) 7 (0.5) 0.93 (0.39,2.24) p = 0.8716 0.91 (0.36,2.33) p = 0.8475 0.84 (0.25,2.80) p = 0.7732 No 2,232 (99.5) 1,381 (99.5) At risk 2,242 1,388 Maternal near-miss at delivery 65/3534 58/2910 7/624 Yes 36 (1.7) 29 (2.1) 1.16 (0.60,2.25) p = 0.6639 1.28 (0.68,2.40) p = 0.4489 0.59 (0.12,2.86) p = 0.5083 No 2145 (98.3) 1343 (97.9) At risk 2,181 1,372 C-section 767/3,552 636/2,938 131/614 Emergency 507 (23.0) 265 (19.3) 1.16 (0.93,1.46) p = 0.1903 1.26 (1.03,1.53) p = 0.0270 0.73 (0.56,0.95) p = 0.0181 Other delivery modes α 1,695 (77.0) 1,105 (80.7) At risk 2,202 1,370 Maternal death 9/3,603 7/2,969 2/634 Yes 8 (0.4) 1 (0.1) 3.45 (0.93,12.78) p = 0.0640 3.15 (0.74,13.40) p = 0.1206 — No 2,232 (99.6) 1,387 (99.9) At risk 2,240 1,388 Modified maternal morbidity and mortality index (MMMI) 749/3,560 575/2,930 174/630 Yes 467 (21.2) 283 (20.6) 1.13 (0.94,1.37) p = 0.1931 1.27 (1.12,1.44) p = 0.0001 0.76 (0.48,1.22) p = 0.2585 No 1,741 (78.8) 1,093 (79.4) At risk 2,208 1,376 PERINATAL AND NEONATAL OUTCOMES Stillbirth at/after 22 weeks GA 21/3,575 19/2,958 2/617 Yes 15 (0.7) 7 (0.5) 1.36 (0.51, 3.58) p = 0.5392 1.25 (0.46,3.38) p = 0.6568 — No 2,205 (99.3) 1,374 (99.5) At risk 2,220 1,381 Stillbirth at/after 28 weeks GA 20/3,560 18/2,945 2/615 Yes 14 (0.6) 7 (0.5) 1.23 (0.47,3.23) p = 0.6704 1.11 (0.42,2.93) p = 0.8356 — No 2,192 (99.4) 1,373 (99.5) At risk 2,206 1,380 Preterm birth (< 37 weeks) 541/2,904 423/2,381 118/523 Yes 362 (23.5) 181 (13.2) 1.53 (1.27,1.84) p = < 0.0001 1.73 (1.32,2.28) p = 0.0001 1.03 (0.68,1.57) p = 0.8812 No 1,181 (76.5) 1,192 (86.8) At risk 1,543 1,373 Preterm birth (< 34 weeks) 120/2,656 93/2,163 27/493 Yes 95 (7.4) 26 (1.9) 3.01 (1.74,5.21) p = 0.0001 3.69 (1.92,7.09) p = 0.0001 1.88 (1.04,3.39) p = 0.0366 No 1,196 (92.6) 1,347 (98.1) At risk 1,291 1,373 Preterm birth (< 32 weeks) 58/2,540 43/2,062 15/478 Yes 50 (4.3) 9 (0.7) 4.59 (1.51,13.94) p = 0.0072 7.58 (2.19,26.19) p = 0.0014 1.88 (0.55,6.44) p = 0.3164 No 1,124 (95.7) 1,364 (99.3) At risk 1,174 1,373 Low birth weight (< 2,500g) 455/3,197 370/2,625 85/572 Yes 287 (15.2) 171 (13.0) 1.16 (0.93, 1.45) p = 0.1817 1.20 (0.95,1.51) p = 0.1201 0.97 (0.68,1.37) p = 0.8501 No 1,608 (84.8) 1,141 (87.0) At risk 1,895 1,312 Very low birth weight (< 1,500g) 88/3,197 76/2,625 12/572 Yes 51 (2.7) 38 (2.9) 1.10 (0.52,2.31) p = 0.8022 1.19 (0.50,2.82) p = 0.6930 0.89 (0.37,2.18) p = 0.8018 No 1,844 (97.3) 1,274 (97.1) At risk 1,895 1,312 Congenital anomaly (at or after 22 weeks) 87/2,755 76/2,346 11/409 Yes 63 (3.7) 24 (2.3) 2.07 (0.94,4.53) p = 0.0694 2.28 (0.80,6.46) p = 0.1214 0.76 (0.39,1.49) p = 0.4297 No 1,647 (96.3) 1,032 (97.7) At risk 1,710 1,056 Congenital anomaly (at or after 28 weeks) 83/2,743 73/2,336 10/407 Yes 59 (3.5) 24 (2.3) 1.91 (0.95,3.85) p = 0.0716 2.11 (0.83,5.35) p = 0.1151 0.75 (0.42,1.34) p = 0.3329 No 1,639 (96.5) 1,032 (97.7) At risk 1,698 1,056 Perinatal death (22-week stillbirths + early neonatal deaths) 41/3,575 38/2,958 3/617 Yes 27 (1.2) 15 (1.1) 1.25 (0.77,2.01) p = 0.3702 1.37 (0.85,2.19) p = 0.1923 0.89 (0.27,2.99) p = 0.8559 No 2,193 (98.8) 1,366 (98.9) At risk 2.220 1,381 Perinatal death (28-week stillbirths + early neonatal deaths) 37/3,560 34/2,945 3/615 Yes 24 (1.1) 14 (1.0) 1.20 (0.78,1.85) p = 0.3980 1.32 (0.88,2.0) p = 0.1850 0.90 (0.27,3.01) p = 0.8617 No 2,182 (98.9) 1,366 (99.0) At risk 2,206 1,380 Neonatal/infant death 32/3,511 30/2,898 2/613 Yes 20 (0.9) 13 (1.0) 0.92 (0.26,3.32) p = 0.9017 1.16 (0.38,3.54) p = 0.7992 — No 2,154 (99.1) 1,346 (99.0) At risk 2,174 1,359 NICU admission 468/3,497 383/2,886 85/611 Yes 321 (14.8) 150 (11.1) 1.63 (1.06,2.50) p = 0.0267 1.90 (1.28,2.82) p = 0.0015 0.82 (0.54,1.26) p = 0.3748 No 1,842 (85.2) 1,206 (88.9) At risk 2,163 1,356 SPMMI 281/3,504 230/2,900 51/604 Yes 196 (9.0) 89 (6.5) 1.57 (0.97,2.54) p = 0.0685 1.76 (1.01,3.05) p = 0.0449 0.86 (0.45,1.63) p = 0.6374 No 1,969 (91.0) 1,273 (93.5) At risk 2,165 1,362 POSTPARTUM OUTCOMES Postpartum haemorrhage 30/3,359 26/2,758 4/601 Yes 12 (0.6) 18 (1.4) 0.51 (0.24,1.08) p = 0.0795 0.39 (0.18,0.84) p = 0.0158 — No 2,062 (99.4) 1,291 (98.6) At risk 2,074 1,309 Postpartum complications: Maternal infection or endometritis 77/3,334 57/2,747 20/587 Yes 53 (2.6) 25 (1.9) 1.35 (1.04,1.74) p = 0.0243 1.39 (0.94,2.06) p = 0.0956 1.22 (0.73,2.04) p = 0.4561 No 2,000 (97.4) 1,278 (98.1) At risk 2,053 1,303 Any readmission in the postpartum period 56/3,350 44/2,761 12/589 Yes 35 (1.7) 21 (1.6) 1.12 (0.70,1.79) p = 0.6421 1.01 (0.58,1.78) p = 0.9677 1.71 (0.42,6.93) p = 0.4524 No 2,033 (98.3) 1,283 (98.4) At risk 2,068 1,304 1 n (%) 2 Pearson’s Chi-squared test *Denominator: All completed pregnancies enrolled at < 20 weeks of gestation ¥ N appears at multiple rows to reflect change in the denominator due to difference in outcome definitions § M/U = Missing or Unknown £ N (%) α: other delivery modes include spontaneous vaginal delivery, instrumental delivery, and planned cesarean section. Some outcomes could not be evaluated because of small numbers or lack of model convergence. Box 1. Study outcomes Maternal and pregnancy Miscarriage before 22 completed weeks of gestation; miscarriage before 28 weeks of gestation Haemorrhage (antenatal, intrapartum and immediately postpartum) Preeclampsia or eclampsia Hypertensive disorders of pregnancy Thromboembolic disease Preterm labour (< 37 weeks) Placental abruption Maternal near-miss indicators at delivery Caesarean section Maternal death (during pregnancy or until 42 days postpartum) Modified maternal morbidity and mortality index (MMMI): at least 1 of the following: haemorrhage at labour and delivery, hypertensive disorders of pregnancy (including preeclampsia/eclampsia), thromboembolic disease, preterm labour, placental abruption; OR near-miss indicator at delivery; OR death. Perinatal and neonatal Stillbirth at or after 22 completed weeks of gestation; stillbirth at or after 28 weeks of gestation Preterm birth < 37 weeks; preterm birth < 34 weeks; preterm birth < 32 weeks Low birth weight (< 2500g); very low birth weight (< 1500g) Congenital anomaly (at or after 22 weeks; at or after 28 weeks) Perinatal death (from 22 weeks gestation to 7 days after birth; from 28 weeks gestation to 7 days after birth) Neonatal death (up to 28 days after birth) Neonatal intensive care unit (NICU) admission Severe perinatal morbidity and mortality index (SPMMI): either stillbirth; OR at least one of the following: hypoxic-ischemic encephalopathy, sepsis; OR admission to the NICU for 7 days or longer; OR neonatal death before hospital discharge. Postpartum Postpartum haemorrhage Infection or endometritis Readmission to the hospital during the postpartum period Table 3. Regression model to determine factors associated with severity of illness among SARS-CoV-2 infected women Covariates in the model Summary Statistics by Symptoms Odds Ratio of Moderate or Severe Symptoms Asymptomatic or Mild Moderate or Severe Odds Ratio OR 95% CI 1, p-value N = 1,939 N = 323 Maternal age at enrollment (years) Median [Q1, Q3] 30 [26,35] 31 [27,35] 1.06 (0.93,1.22) 0.374 Missing/Unknown 19 0 Presence of medical conditions 0 953 (88.9%) 119 (11.1%) — 1 or more conditions 930 (82.4%) 199 (17.6%) 1.27 (0.97,1.66) 0.088 Missing/Unknown 56 5 Vaccination status Never vaccinated 615 (82.6%) 130 (17.4%) — Partially vaccinated 147 (86.0%) 24 (14.0%) 0.62 (0.38,1.01) 0.056 Fully vaccinated, last dose before pregnancy 419 (86.7%) 64 (13.3%) 0.84 (0.57,1.24) 0.384 Fully vaccinated, last dose during pregnancy 591 (86.8%) 90 (13.2%) 0.47 (0.47,1.02) 0.063 Missing/Unknown 167 15 Variant of concern pre-Omicron 1,549 (84.5%) 285 (15.5%) — Omicron 390 (91.1%) 38 (8.9%) 0.52 (0.34,0.78) 0.002 1 Odds Ratios determine association after adjusting for other covariates in the model. £: Maternal age OR per 5-year increase Variant period Variant of concern (VOC) designation was determined based on country-specific genetic sequencing data from the Global Initiative on Sharing All Influenza Data (GISAID), which had been expanded to include SARS-CoV-2 data [9]. The assigned VOC was the variant predominant in 75% or more cases in the participant’s country at the pregnancy start date. Participants with an Omicron VOC designation were classified as 'Omicron' and those with any other VOC designation were grouped under 'pre-Omicron'. Vaccination status Participants were considered fully vaccinated if they had received a complete primary series (at least one dose for J&J/Janssen or CanSino and at least two doses for all other vaccines); partially vaccinated if they had only received one dose (aside from J&J/Janssen or CanSino); and never vaccinated if they had not received any doses. The “fully vaccinated” group was divided according to whether their most recent dose was during or before pregnancy. Data management Data were collected using paper-based or tablet-based case report forms and subsequently key-entered into a validated web-interface electronic data capture system on the OpenClinica® platform (OpenClinica LLC, Waltham, Massachusetts, USA). Country-specific user accounts were password-protected, with a hierarchy of data access depending on each researcher’s role. Data sent to the server were encrypted using Secure Hash Algorithm 256-bit (SHA256) with Rivest-Shamir-Adleman (RSA) encryption. All study records were anonymised with unique study numbers. A standardised data management plan for data collection, curation, and discrepancy management was coordinated by WHO through web-based dashboards and periodic PDF reports. Statistical analysis Participants with unknown infection status were excluded from both primary and sensitivity analyses. Characteristics of enrolled participants including country, demographics, clinical and obstetric history, SARS-CoV-2 infection status during pregnancy, and VOC designation were summarized using appropriate descriptive statistics. Categorical variables were presented as proportions, while continuous variables were summarized using measures of central tendency (mean or median) and dispersion (standard deviation or quartiles), based on variable distribution. Comparisons of proportions were conducted using Pearson’s chi-squared test or Fisher’s exact test, and comparisons of continuous variables were conducted using the Wilcoxon rank sum test. A p-value < 0.05 was considered statistically significant. For the primary analysis, participants with confirmed or probable SARS-CoV-2 infection during pregnancy were considered as “SARS-CoV-2 infected”, and those with confirmed or probably no infection during pregnancy were considered as “uninfected” ( Fig. 1 ). Risk of adverse pregnancy outcomes related to SARS-CoV-2 infection during pregnancy were evaluated by comparing the absolute risk of outcomes in the infected group to the uninfected group and by estimating the relative risk (RR) using log-binomial generalized linear mixed models (GLMMs). We reviewed forest plots by country for each outcome and stratified by VOC period to identify countries with extreme RRs or disproportionately large influence on pooled estimates. Models were refitted, excluding these countries, and evaluated for consistency. Country-specific random intercepts were used to account for potential clustering. All models were adjusted for maternal age at enrollment and presence of at least one comorbidity. Modification of effects by VOC was evaluated by fitting the model with an interaction term between SARS-CoV-2 infection and VOC period, and RR estimates were reported for combined sample and stratified for the pre-Omicron and Omicron periods. For all estimates, 95% confidence intervals (CI) were provided. In sensitivity analyses, these models were repeated twice: first by adding the “possibly infected during pregnancy” group to the "infected” group and second, by adding the “possibly infected” group to the “uninfected” group. For each adverse pregnancy outcome of interest, denominators were established based on contribution to the gestational period at risk and timing of enrolment in the study, as some outcomes such as miscarriage occur only within specific time periods (Additional File 2 - Table 2). Those lost to follow up prior to completion of pregnancy and those whose SARS-CoV-2 testing occurred more than 48 hours after delivery were excluded. For preterm birth, an additional subgroup analysis was conducted. In the main analysis, the sample was restricted to participants with positive SARS-CoV-2 tests occurring prior to the gestation week for the preterm birth outcome being considered, but otherwise included all live births. For the subgroup analyses, further restrictions were applied: only participants with 1) enrollment dates, or 2) negative SARS-CoV-2 testing dates, prior to the gestation week were considered ensuring temporal alignment between infection status and outcome risk. To explore determinants of illness severity within the SARS-CoV-2 infected subgroup, a mixed effects logistic regression model, using country-specific random intercepts, was fitted to evaluate the association between maternal age, underlying conditions, vaccination status and VOC period with illness severity. Odds ratios (ORs) for moderate or severe illness compared to asymptomatic or mild infection and 95% CI were estimated. The risk of pregnancy, perinatal, and neonatal outcomes in the moderate or severe illness group relative to the asymptomatic or mild group, controlling for maternal age and presence of underlying conditions were assessed using the GLMM model as above. Analyses were conducted using R version 4.4.2 (R Foundation for Statistical Computing, Vienna, Austria). Results Study population Of 22,047 pregnant women screened at 43 facilities in 10 countries, 16,007 (72.6%) were enrolled. Study flow, assignment to infection status groups, and final analytic samples are shown in Fig. 2. Figure 2. Study flowchart and algorithm for determining infection status during pregnancy Based on laboratory testing and clinical diagnoses over the study, 2,189 (13.7%) participants were classified as having confirmed SARS-CoV2 infection during pregnancy, 116 (0.7%) had probable infection, 7,332 (45.8%) had possible infection, 402 (2.5%) probably had no infection, 1,053 (6.6%) had confirmed no infection during pregnancy, and 4,915 had unknown infection status. The distribution of participants by SARS-CoV-2 infection status across the participating countries is presented in Additional File 3 - Table 3 . Most enrolled participants began their pregnancies in 2021 or 2022 ( Additional File 4 - Fig. 1 ). Of 15,914 with available data, 11,847 pregnancies (74.4%) began before the period of Omicron predominance (pre-Omicron) and 4,067 (25.6%) began during the period of Omicron predominance ( Additional File 5 - Fig. 2 ). Most infections (80.8%) also occurred in the pre-Omicron period. Women infected with SARS-CoV-2 during pregnancy were more likely than uninfected women to be multigravida (73.4% vs 69.0%, p < 0.004), single or previously married (24.3% vs 13.5%, p < 0.001), to have higher education (41.8% vs 36.6%, p < 0.001), and to be unemployed or working in informal jobs (57.9% vs 45.0%, p < 0.001) (Table 1 ). Both groups were similar with respect to age at enrollment and alcohol consumption. Although the median gestational age at enrollment was 36 weeks for both groups, a higher proportion of infected women were enrolled earlier in pregnancy (6.4% vs 4.3% before 14 weeks, 22.0% vs 10.7% between 14–27 weeks, 71.6% vs 85.0% after 27 weeks, p < 0.001). Most study participants were seen in tertiary care hospitals, more commonly among those with infection (94.7% vs 80.4%, p < 0.001). Conditions such as heart disease, lung disease, hypertension, and diabetes were consistently more prevalent in the infected group; however, these differences were not statistically significant (Additional File 6 - Table 4) . Additionally, considering the overall number of pre-existing conditions, the infected group was less likely to report one medical condition (41.2% vs 48.8%) and only slightly more likely to report two or more conditions (9.7% vs 9.3%). Vaccination status by the end of the study differed significantly between both groups. Uninfected participants were more likely to have never been vaccinated (45.3% vs 35.3%) and infected women were more likely to be fully vaccinated before pregnancy (23.7% vs 14.5%) (Table 1 ). Characteristics for all infection group categories can be found in Additional File 7 - Table 5 . Maternal and pregnancy outcomes Of the participants included in the analytic sample, 604 (5.4%) participants were lost to follow up before end of pregnancy, leaving 2,246 participants with confirmed or probable infection and 1,390 participants with confirmed or probably no infection. Participants classified as possibly infected (n = 6,852) were considered in the sensitivity analysis. Accounting for variation by country and after adjusting for maternal age and presence of at least one comorbidity, the risks of emergency Cesarean delivery (RR 1.26, CI 1.03–1.53) and the composite outcome of maternal morbidity and mortality according to the modified MMMI (RR 1.27, CI 1.12–1.44) were significantly higher among women infected with SARS-CoV-2 compared to the infected group during the pre-Omicron period (Table 2 and Additional File 8 - Fig. 3 ). During the Omicron era, RR estimates for both of these outcomes were no longer significantly elevated, and the risk for emergency Cesarean delivery was significantly lower among women infected with SARS-CoV-2. None of the other maternal outcomes evaluated had significantly elevated RRs in either variant period ( Table 2 ) . Eight maternal deaths were recorded out of 2,240 (0.4%) SARS-CoV-2-infected women (3 due to confirmed COVID-19, 1 due to postpartum abdominal infection, and 4 unspecified), and 1 out of 1,388 (0.1%) non-infected women (due to pre-eclampsia). Of these nine deaths, 7 occurred during the pre-Omicron era and two during the Omicron era. Perinatal and neonatal outcomes During the pre-Omicron period, the adjusted risks of preterm birth < 37 weeks (RR 1.73, CI 1.32–2.28), as well as < 34 weeks (RR 3.69, CI 1.92–7.09) and < 32 weeks (RR 7.58, CI 2.19–26.19) were significantly higher in the infected group compared to the uninfected group. During the Omicron period the only RR that remained significantly elevated was for preterm birth < 34 weeks (RR 1.88, CI 1.04–3.39). The RR point estimate for preterm birth < 32 weeks was similar to that for 34 weeks; however, this association was not statistically significant (RR 1.88, CI 0.55–6.44) (Table 2 and Additional File 8 - Fig. 3 ). In the first subgroup analyses for preterm birth, which was restricted to those with enrolment dates prior to the respective gestation week, RRs were slightly attenuated but remained significant for preterm birth at all three gestation ages in the pre-Omicron era ( Additional File 9 - Table 6 ). The significantly increased RR for preterm birth < 34 weeks observed in the Omicron era for the main analysis was no longer observed. In the second subgroup analysis based on dates of negative testings, no significant RRs were observed. The risk of NICU admission was significantly higher in the infected group during the pre-Omicron period (RR 1.90, CI 1.28–2.82), as was the risk of SPMMI (RR 1.76, CI 1.01–3.05), but not during the Omicron period. No significant differences were found between groups for other perinatal and neonatal outcomes evaluated. Postpartum outcomes The risk of postpartum complications was significantly higher among infected women overall (RR 1.35 CI 1.04–1.74). During the pre-Omicron period, women with SARS-CoV-2 infection had a significantly lower risk of hemorrhage within the 42 days after delivery compared to the uninfected group (RR 0.39, CI 0.18–0.84) (Table 2 and Additional File 8 - Fig. 3 ). Sensitivity Analysis Results for the first sensitivity analysis, which combined “possibly” infected women with the “infected” group, are shown in Additional Files 10–12: Tables 7–9 . In this analysis, RR point estimates for most outcomes were similar to those in the main analysis or attenuated, with some outcomes no longer significant (e.g., emergency C-section and MMMI) and others becoming significant despite similar RRs (e.g., pre-eclampsia/eclampsia and hypertensive disorders or pregnancy). The only exception to this was for stillbirth and perinatal death, for which RR estimates were higher relative to the main analysis in the pre-Omicron period (e.g., for perinatal death from 28 weeks, the RR was 2.05 (CI 1.44–2.92)). Due to small numbers, these outcomes could not be evaluated during the Omicron period. In the first sensitivity analysis, the only outcomes with significantly elevated RRs for the infected group in the Omicron period were preterm birth < 34 weeks (RR 2.20, CI 1.46–3.32) and preterm birth < 32 weeks (RR 1.40, CI 1.07–1.85). Risks for congenital anomalies were notably lower (RR 0.40, CI 0.18–0.86 after 28 weeks). Results of the second sensitivity analysis, including women “possibly” infected during pregnancy in the uninfected group, are shown in Additional Files 13–15 – Tables 10–12 . Overall, notable differences with the main analysis include an increased risk for maternal hemorrhage for those in the infected group in the pre-Omicron era (RR 2.42, CI 1.87,3.14) and decreased risks of miscarriage (RR 0.73, CI 0.56–0.97; Omicron) and of stillbirth (RR 0.55, CI 0.36–0.82 for 28 weeks; pre-Omicron). In this second sensitivity analysis, the only outcomes with significantly elevated RRs for the infected group in the Omicron period were congenital anomalies (RR 1.94, CI 1.02–3.70 after 28 weeks). Severity of SARS-CoV-2 infections and related outcomes Data on SARS-CoV-2 infection-related symptoms were available for 2,262 (98.1%) women with infection. Of these, 1939 (85.7%) were asymptomatic or had mild symptoms and 323 (14.3%) had moderate to severe symptoms. The most frequently reported symptoms during the pre-Omicron era were fever (36.7%), cough (28.9%), and myalgia (27.9%) whereas rhinitis (27.7%), fever (27.0%) and headache (26.8%) were more frequent during the Omicron period ( Additional File 16 - Fig. 4 ). Additionally, the prevalence of moderate to severe infection was significantly lower during the Omicron period compared to the pre-Omicron period (8.9% vs 91.1%), with an adjusted OR of 0.52 (CI 0.34–0.78), after adjusting for maternal age, comorbidities, and vaccination status (Table 3 ). Vaccination status revealed a protective trend against moderate or severe symptoms. Compared to individuals who were never vaccinated, those who were partially vaccinated had 38% lower odds (OR 0.62; CI 0.38–1.01) and those fully vaccinated during pregnancy had 53% lower odds (OR = 0.47, 95% CI: 0.47–1.02). These findings were borderline significant, indicating a possible protective effect of vaccination, particularly when administered during pregnancy. Fully vaccinated individuals whose last dose was before pregnancy showed no significant reduction in risk (OR = 0.84, 95% CI: 0.57–1.24). Pregnant women who experienced moderate to severe illness were at significantly increased risk of a near-miss indicator at delivery (RR 3.45, CI 2.20–5.49), MMMI (RR 1.29, CI 1.02–1.61) and C-section (RR 1.36, CI 1.08–1.71) ( Additional File 17 - Table 13 ). Table 3 . Regression model to determine factors associated with severity of illness among SARS-CoV-2 infected women Discussion In this large multi-country prospective cohort study, conducted primarily in LMICs, we evaluated whether SARS-CoV-2 infection during pregnancy increases the risk of adverse maternal, perinatal, neonatal, or postpartum outcomes compared with women without infection during pregnancy, in both pre-Omicron and Omicron periods of SARS-CoV-2 variant predominance. We found that the risks of several adverse outcomes, such as emergency Cesarean delivery, MMMI, preterm birth, NICU admission, SPMMI and postpartum hemorrhage were significantly increased following SARS-CoV-2 infection in pregnancy during the pre-Omicron era. However, these risks were no longer significantly elevated during the Omicron period, for all outcomes except preterm birth before 34 weeks of gestation. A strength of our study was its prospective design, which used rigorous definitions for both exposure and outcomes. We determined SARS-CoV-2 infection status during pregnancy through universal virologic testing and serial serologic assessments. In contrast, previous individual studies and meta-analyses on this topic have been limited by differing and inexact definitions of exposure status, e.g., relying on a single virologic test to classify participants as “negative”, increasing the risk of misclassification bias. Others preferentially identified cases with symptomatic infection or at delivery, potentially skewing results toward those more likely to experience adverse outcomes [ 1 , 2 ]. Another strength of our study was the inclusion of a large sample of participants from LMICs in distinct parts of the world. Most prior studies on COVID-19 and pregnancy have been conducted in HICs, where greater access to higher-level care could improve illness-related outcomes while potentially increasing certain clinician-initiated interventions, such as emergency Cesarean section [ 10 ]. Conversely, in many LMICs, higher baseline rates of outcomes like preterm birth can make it more challenging to detect small absolute increases associated with SARS-CoV-2 infection [ 11 ]. Differences in underlying comorbidities could also modify risk. Finally, our study is among the few that have evaluated RRs of adverse pregnancy outcomes by comparing pregnant women with and without SARS-CoV-2 infection during the Omicron period. This provides a more accurate reflection of current risks than data collected earlier in the pandemic [ 3 – 5 ]. A main limitation of our study was that it was originally designed and powered to incorporate serologic testing at a time when few women had previous infection, so the presence of antibody would reflect recent infection [ 7 ]. However, by the time the study started in many settings, most women were already seropositive. Additionally, data had also emerged that SARS-CoV-2 antibodies could persist over 12 months, meaning that seropositivity could reflect infection prior to pregnancy [ 12 ]. Excluding participants whose infection status was not confirmed or probable from the primary analysis improved the accuracy of comparisons, but it also reduced our effective sample size and made our study sample less representative of the general antenatal population, especially as the pandemic progressed. Given the loss of statistical power [ 7 ], some caution needs to be taken in interpreting the lack of significant RRs for adverse outcomes in the Omicron era. Pregnant women with SARS-CoV-2 infection continued to have a significantly increased RR of preterm birth < 34 weeks during the Omicron period. For the less common outcome of preterm birth < 32 weeks, point estimates remained higher but were no longer statistically significant. It is reassuring that Omicron-era RR point estimates for most outcomes, including preterm birth < 37 weeks, were not increased. Our pre-Omicron era findings align with numerous previous studies demonstrating severe disease and elevated risks of adverse pregnancy-related outcomes associated with SARS-CoV-2 infection during pregnancy earlier in the pandemic [ 1 , 2 ]. Our Omicron era findings differed from another multi-country study by Villar et al, which observed increased composite risks of severe maternal, perinatal, and neonatal morbidity, especially for women with symptomatic COVID-19 [ 4 ]. A key methodological distinction lies in the timing and classification of Omicron exposure. The prior study included women who delivered within the first six months of the Omicron era using a global date cutoff. In contrast, our analysis defined Omicron exposure based on country-specific data, including only pregnancies that started when more than 75% of circulating variants were Omicron [ 10 ]. This approach may have reduced misclassification with pre-Omicron infections and better captured the full gestational impact of Omicron-dominant infections. Neither ours nor the Villar study conducted genotyping for individual infections. Additionally, Villar’s cohort included more HIC data, whereas ours primarily included data from LMICs. A recent study in Botswana found no differences in adverse maternal and neonatal outcomes among women with and without SARS-CoV-2 infection in pregnancy in the period of Omicron predominance [ 5 ]. Another potential explanation for differences between our findings and those of Villar et al. may relate to our use of serologic testing to help define those without infection during pregnancy. As part of our sensitivity analyses, we included those with “possible” infection during pregnancy (whose only evidence of infection was a positive serologic test) as part of the uninfected group, which more closely aligns with previous studies that have not incorporated serologic testing. However, this did not result in significantly increased RR estimates in the Omicron era for most outcomes, except for congenital anomalies, an association that should be further explored. The varied findings in our sensitivity analyses likely reflect the effects of both increased power due to larger numbers and increased misclassification (as the seropositive are a mix of those infected during pregnancy and those infected earlier). Differences in specific RR estimates in prior studies, such as findings of an increased risk of stillbirth or maternal death in some studies but not others, may depend on the degree of exposure status misclassification [ 1 , 2 ]. The decline in risk of adverse outcomes during the Omicron period could be attributed to a decrease in virulence of Omicron variants, or to increased prior immunity, from previous infection, vaccination, or both [ 13 ]. Several studies have demonstrated a decrease in overall severity of illness in pregnancy during the Omicron period compared with earlier periods, as observed in nonpregnant adults [ 3 , 14 ]. We found that among those with SARS-CoV-2 infection, women had lower odds of moderate or severe illness during the Omicron era compared to the pre-Omicron era, regardless of previous vaccination. In turn, controlling for variant period, the odds of moderate to severe illness were around 53% lower if women were fully vaccinated with the latest dose in pregnancy compared with no vaccination. Although in a borderline statistical significance, this finding is important because, among all those with infection in pregnancy, women with more severe illness had higher risks of adverse outcomes such as maternal near-miss at delivery, MMMI, and C-section (this analysis was not sufficiently powered to evaluate separately by variant period) [ 6 ]. Our findings have implications for risk-benefit assessments for interventions in pregnancy, including vaccination. As of September 2025, WHO recommendations are for pregnant women to receive one dose of COVID-19 vaccine in each pregnancy [ 15 ], based on the increased risk of adverse outcomes in pregnancy observed in previous literature [ 1 , 2 ], along with numerous studies showing that vaccines are safe and effective in preventing severe COVID-19 illness for pregnant women and infants, even in the Omicron era [ 16 ]. The findings of this study contribute to those considerations and provide reassurance that the risk of adverse outcomes has decreased as the pandemic has progressed. However, the ongoing signals for an increased risk of early preterm births for women infected during Omicron-era, and potentially for additional outcomes in sensitivity analyses with greater sample size, mean that there may be ongoing risks. We did not have data from more recent Omicron sub-variant periods. Continued monitoring can evaluate evolving risk profiles of new variants [ 17 ], although the large proportion of women with prior hybrid immunity is reassuring that we will not go back to the morbidity seen earlier in the pandemic [ 18 ]. However, an important consideration is that the lower risks observed in the Omicron period might be related to increased overall vaccination levels—and ongoing vaccination in pregnancy—which we were not fully able to evaluate. A disproportionate number of vaccinated individuals were excluded from the current analysis, preferentially from the uninfected group, based on our use of negative serologic testing at the end of pregnancy to confirm lack of infection. Serologic testing cannot distinguish natural from vaccine-induced antibodies following receipt of inactivated vaccines, which were used by almost a third of those vaccinated and almost 15% of the entire study sample. The separate COVID-19 vaccine evaluation from this study, conducted among the entire study population of 16,007 participants without limiting to those with known infection status, will provide additional information to the risk-benefit equation. Conclusions In summary, this prospective cohort study among pregnant women in 10 countries, one of the largest evaluating COVID-19 and pregnancy in primarily LMICs, found that SARS-CoV-2 infection during pregnancy increased the risk of several maternal, perinatal, and neonatal outcomes mainly during the pre-Omicron era. These data provide reassurance that during the Omicron era, when a large proportion of pregnant women also have immunity from prior infection or vaccination, relative risks are largely attenuated. However, some evidence of increased risk remains, for example in preterm births < 34 weeks of gestation. Continued evaluation of data on SARS-CoV-2 illness and pregnancy outcomes, especially in the context of emerging variants and newer Omicron sub-variants, and further exploration of the effects of COVID-19 vaccination during the Omicron and Omicron sub-variant periods would be valuable. As most prior data on COVID-19 and pregnancy outcomes have been from HICs, this study also highlights the importance of generating quality outbreak-related data in LMICs, to ensure the health of pregnant women and their neonates globally. Declarations Ethics approval and consent to participate This study was conducted in accordance with the ethical principles outlined in the Declaration of Helsinki for research involving human participants and relevant national and institutional guidelines. The generic protocol received approval from the WHO Ethics Review Committee (WHO ERC). Country-specific protocols were also submitted for review and approved by both the WHO ERC and the Institutional Review Boards (IRBs) of each participating country. Written informed consent or assent was obtained from all participants prior to their inclusion. Ethics approval committees and timelines are as follows: Generic protocol - World Health Organization (WHO): WHO Ethics Review Committee (ERC) approval granted on 18 August 2020 (Ref: CERC.0008), with continuing review approval on 1 September 2021 and amendment approval on 5 July 2022 (Ref: CERC.0008). Country-adapted protocols: Argentina: Ethical approval obtained from the Pan American Health Organization Ethics Review Committee (PAHOERC) on 4 November 2021 (Ref: PAHOERC.0428.03), and from the following local ethics committees: Comité de Ética Independiente del CREP on 22 September 2021; Ref 3_21, Comité de Ética del Hospital Materno Neonatal “Eloisa Torrent de Vidal” on 14 June 2021, and Comité de Ética del Hospital Privado – Centro Médico de Córdoba on 10 September 2021; Ref HP4-346. Brazil: Ethical approval obtained from PAHOERC on 2 July 2021 (Ref: PAHOERC.0369.02) and on 23 March 2023, and from the following local ethics committee for all centers: Comissão Nacional de Ética em Pesquisa (CONEP) on 30 June 2021 (Ref: 4.817.831), with amendments approved on 6 June 2023. Burkina Faso: Ethical approval requirements were waived by the WHO African Region Ethics Review Committee (AFRO ERC) on 3 August 2021 (Ref: AFR/ERC/2021/8.2) and on 23 June 2023 (Ref: AFR/ERC/2023/6.10). Local approval was obtained from the Comité d’éthique pour la recherche en Santé (CERS) on 2 June 2021, with amendments approved on 7 June 2023. Chile: Ethical approval was obtained from the World Health Organization (WHO) / Pan American Health Organization (PAHO) Ethics Review Committee (Ref. PAHOERC.0590.02; approval dated 16 December 2022), as well as from the following local ethics committees in Chile: Comité de Ética Científica de la Dirección de Servicio de Salud Araucanía Sur (approval dated 21 October 2021; Ref. 244), Comité de Ética Científica de la Dirección de Servicio de Salud Araucanía Sur (approval dated 23 March 2023; Ref. 57), Comité Ético Científico del Servicio de Salud del Reloncaví – Hospital Puerto Montt (approval dated 26 July 2021; Ref. 16), and Dirección de Servicio de Salud Araucanía Sur – Hospital Dr. Hernán Henríquez Aravena (approval dated 30 March 2023; Ref. 2553). Ghana: WHO AFRO ERC approval obtained on 26 February 2021 (Ref: AFR/ERC/2021/2.2), with local approvals granted by the Ghana Health Service Ethics Review Committee on 26 April 2021 and 11 November 2021 (Ref: GHSERC 017/02/21), and by the University of Ghana IRB on 28 October 2021 (IRB00006220). Kenya: WHO AFRO ERC approval on 25 February 2021 (Ref: AFR/ERC/2021/2.4) with continuing approval on 14 April 2023 (Ref: AFR/ERC/2023/4.1). Local approvals from Aga Khan University, Nairobi on 12 May 2021 (Ref: 2020/IERC-153 (v2)) and 6 March 2023 (Ref: 2020/IERC-153 (V3)), and from the National Commission for Science, Technology and Innovation (NACOSTI) on 9 June 2021 (Ref: 336896). Pakistan: WHO Eastern Mediterranean Regional Ethics Review Committee (EMRERC) approval with waiver in 2021 and 10 December 2023. Local approvals obtained from the Aga Khan University Ethics Review Committee on 26 February 2023 (Ref: 2023-5838-24122), with amendments approved on 17 February 2022 (Ref: 2022-5838-20665), 18 May 2022 (Ref: 2022-5838-21504), and 8 November 2022 (Ref: 2022-5838-23158). National Bioethics Committee approvals were granted on 23 February 2021 (Ref: 4-87/COVID-62/NBC/21), with amendment and extension approvals on 26 May 2021 and 5 September 2022 (Ref: 4-87/COVID-62/22/294). Philippines: WHO Western Pacific Regional Ethics Review Committee (WPRO-ERC) approval on 27 August 2021 (Ref: 2021.14.PHL.3.MCN). Local approvals from the Single Joint Research Ethics Board (SJREB) on 19 May 2021 (Ref: SJREB-2020-30) and 20 February 2023 (amendment), the University of the Philippines Manila Research Ethics Board (UPMREB) on 9 June 2021 (Ref: 2020-320-01-SJREB) and 10 March 2023 (continuing review; Ref: IRB 2020-18-4), and the Research Institute for Tropical Medicine – Department of Health on 11 June 2021 (Ref: IRB 2020-18-2). Spain: Comité Ético de Investigación de la Dirección General de Salud Pública y Centro Superior de Investigación en Salud Pública approval obtained on 21 December 2020 (Ref: 20201221/06), and Comité Ético de Investigación Clínica del Hospital Universitario Doctor Peset de Valencia approval obtained on 29 November 2021. Tunisia: EMRERC approvals (with waiver) on 19 October 2021 and 3 March 2023, on the basis of local approvals obtained from: the Comité d’éthique du Centre de Maternité et de Néonatologie de Tunis on 23 July 2021, and from the Comité d’éthique Biomédicale de l’Institut Pasteur de Tunis on 29 July 2021 (Ref: 2021/12/I/LR16IPT/V1), with amendment approval on 26 June 2023 (Ref: 2022/12/I/LR16IPT/Amendment/V1). Informed Consent: Obtained from all study participants prior to enrolment in the study, and in accordance with WHO ERCs and local ethics committee requirements. Consent for publication Not applicable. This manuscript does not contain any individual’s data in any form (including individual details, images, or videos) that require consent for publication. Availability of data and materials Research study data that support the findings of this study may be requested by completing a concept note available from the corresponding author. An anonymized dataset will be made available upon approval of the multi-country editorial board with data share agreement from the country principal investigators. Competing interests The authors declare no competing interests. Funding The project was partially supported by the Bill and Melinda Gates Foundation, Ref: Investment ID INV-041181, the United States Department of State, the German Federal Ministry of Health (BMG) COVID-19 Research and development support to the World Health Organization (WHO), Ref: MG 2022 support to WHO SPRP ACT-A, and UNDP-UNFPA-UNICEF-WHO-World Bank Special Programme of Research, Development and Research Training in Human Reproduction (HRP), a co-sponsored programme executed by WHO. The funders had no specific role in the conceptualization, design, data collection, analysis, decision to publish, or preparation of the manuscript. The authors alone are responsible for the views expressed in this article and they do not necessarily represent the views, decisions, or policies of the institutions with which they are affiliated. RHR TRIMS Project ID no. A66012” Authors' contributions WHO COVID-19 Pregnancy Cohort Study Group The following are the manuscript authors comprising the WHO COVID-19 Pregnancy Cohort Study Group. In each Implementing Country Team, the leads/principal investigators are followed by remaining group members in alphabetical order: WHO Coordinating Team: 1 Edna Kara § , Sami L Gottlieb § , Nathalie J Broutet , Anna Thorson, Marie Delnord, Ibukun-Oluwa Omolade Abejirinde. WHO Data Management and Analysis Team: 1 Ronaldo Silva £ , Soe Soe Thwin £ , Daniel Giordano, Ndema Abu Habib. Implementing Country Teams (countries in alphabetical order) : Argentina 2 : Edgardo Abalos*. Brazil 3 : José G Cecatti*; Maria L Costa; Renato T Souza. Burkina Faso 4 : Seni Kouanda*; Desiré L. Dahourou; Henri Gautier Ouedraogo. Chile 5 : Sergio Munoz*; Gerardo Espinoza; Araceli Saavedra. Ghana 6 : Kwasi Torpey*; Chris Guure; Ernest Maya; Emefa Modey. Kenya : Marleen Temmerman 7 *; Rodney D. Adam 7 ; Ingrid Gichere 7 ; Sura Mandeep 8 . Pakistan 9 : Sarah Saleem*; Najia Ghanchi; Saleem Jessani. Philippines : Erlidia Llamas-Clark 10,11 *; Emmanuel S Baja 10 ; Mayan U Lumandas 12 . Spain 13 : Alejandro Orrico-Sánchez*; Antonio Carmona. Tunisia : Henda Triki 14,15 *; Mariem Gdoura 14-16 . Also see in the acknowledgements the full list of contributors in each country. § Co-lead authors £ Co-lead analyst/statisticians, *Principal Investigators. Affiliations Department of Sexual and Reproductive Health and Research including the Human Reproduction Programme (HRP), World Health Organization, Geneva, Switzerland Centro Rosarino de Estudios Perinatales (CREP), Rosario, Argentina Department of Obstetrics and Gynecology, University of Campinas, Brazil Institut de Recherche en Sciences de la Santé (IRSS), Uagadugu, Burkina Faso University de La Frontera, Temuco, Chile School of Public Health, University of Ghana, Accra, Ghana Aga Khan University, Nairobi, Kenya Pumwani Maternity Hospital Department of Community Health Sciences, Aga Khan University, Karachi, Pakistan. University of the Philippines, Manila, Philippines Institute of Child Health and Human Development, National Institutes of Health, University of the Philippines, Manila, Philippines. Research Institute for Tropical Medicine-Department of Health, Manila, Philippines Department of Vaccines Research, Fundación Para el Fomento de la Investigación Sanitaria y Biomédica de la Comunitat Valenciana (Fisabio), Valencia, Spain Research Laboratory "Virus, Vectors and Hosts”, LR20IPT02, Pasteur Institute, University Tunis El-Manar (UTM), Tunis, Tunisia Clinical Investigation Center (CIC2016IPT02), Institut Pasteur de Tunis, University of Tunis El Manar. Faculty of Pharmacy, University of Monastir, Monastir, Tunisia The original generic protocol of the study was conceptualized and had the first draft written by the staff of WHO. The adaptation of the generic protocol to each participant country´s characteristics was performed by each country´s PI and Co-PIs with the support of the WHO team. The current manuscript was first drafted by EK and SLG with initial inputs from by-lined authors. Data collection was performed by the local study teams. Data was managed, cleaned and processed by DG. The statistical analysis was conducted by RS and SST, who also provided input to the initial manuscript. Initial interpretation of findings was conducted by EK, SLG, RS and SST. A second round of input was performed by the WHO team including all COVID-19 PCS investigators and co-investigators. A third round of input was received from all authors, who also read and approved the final manuscript to be submitted for publication. The authors alone are responsible for the views expressed in this article, and they do not necessarily represent the views, decisions, or policies of the institutions with which they are affiliated. Additional contributors in each country are listed in the acknowledgements. Acknowledgements We extend our heartfelt gratitude to the women who participated in this study. We also wish to express our appreciation to the institutions and individuals who contributed to this project’s design and implementation. This includes researchers, study coordinators, data collectors, data clerks, and other partners, as well as the staff from the Ministries of Health and WHO Regional and Country Offices. Hospital site investigators are listed below, followed by any additional collaborators by country and in alphabetical order. Argentina: Jesús D Aguirre; Lucia Bóccoli; Pablo Gola; Elba MA Morales; Constanza Poenitz; Savino Gil Pugliese; Sofía Roggi; Gabriela C Taborda. Additional collaborators: Raúl H Capra; Micaela Y Colussi; Hernán G De La Rocha Morales; Florencia Ducart Díaz; Karina MA Fernández; Soledad C Fleita; Silvia Galetto; Florencia L García; Martín L García; Luis G Mercado; Jesica N Esquivel Quiñones; Sofía G Salguero; Luciana Simes; Nicole Toutain. Brazil: Mário D Corrêa-Júnior; Edson V Cunha Filho; Samira M Haddad; Débora F Leite; Marília GQ Luz; Ana S Picoloto; Carla Silveira; Ricardo P Tedesco; Evelyn Traina. Additional collaborators: Sabrina Aguiar; Pedro Albuquerque; Julia S Almeida; Gabriela S Alves; Junia Andrade; Luísa S Andrade; Artur A Antolini; Annerose Barros; Guilherme Bese; Anne Bergmann; Mariana Brasileiro; Gislânia PF Brito; Laura F Brum; Telma RM Campello; Danilo G Cardim; Anna TS Cardoso; Bianca S Carrara; Aline Cavalcante; Marcela MT Cavalcante; Euriane C Costa; Juliana Costa Santos; Mariany C Cottet-Moratori; Sarah Dariva; Helena M Dreschler; Karayna G Fernandes; Karina MA Fernández; Leydiane A Ferreira; Josiane Fonseca De Oliveira; Juliana S Franciscato; Hellen T Fuzii; Silvia Galetto; Rafael B Galvão; Andrezza A Guerra; Luciano Guimaraes; Luciana Iadoccico; Giuliane J Lajos; Amanda B Lima-Silva; Rhayssa Lucena; Adriana G Luz; Ellen Machado; Manoela Maffei; Sérgio HA Martins-Costa; Aline D Maranhão; Silvia B Mazon; Jussara Mayrink; Lorena R Medeiros; Marina Melo; Elias F Melo Junior; Sherly Metelus; Isabella Monteiro; Charles M’poca; Ana L Muller; Bárbara SP Neres; Patricia Nessralla; Guilherme M Nobrega; Adriane Oliveira; Thais O Oliveira; Melina MS Oliveira; Yasmin F Oliveira Silva; Maria LR Oppermann; Rodolfo C Pacagnella ; Ana S Picoloto; Laiza S Quadro; José G Ramos; Gustavo Raupp; Carolina C Ribeiro-Do-Valle; Clélia A Salustrino; Sabrina Savazoni; Eduardo Serra; Arthur Simoes; Carla L Silva; Deborah Silva; Elisabete P Silva; Fabricio Souto; Camila Cd Souza; Natália C Souza; Luiza Q Stein; Aline Tosetto; Juliana Trevizo; Janete Vettorazzi. Burkina Faso: Ignace Béré; Ousmane Bague; Todara Dabal/Yabre; Anselme KP Somda; Sylvain Ko; Frederic Paul Patarb-Taale Kobinde; Philippe Tassembedo; Toudala Paré; Honorine Tougouma; Hamado Ouedraogo; François Yameogo. Additional collaborators: Blandine Bonane Thieba; Rebeca Compaore; Issa Kaboré; Tani Sagna; Angèle Zan. Chile: Margot Acuña; Evelyn Brunman; Jose Caro; Dorothy Fica; Arantza Solis; Valeria Urbina. Ghana: Richard Anthony; Franklin Asiedu-Bekoe; Kennedy Brightson; Evelyn Bonney; Joycelyn Dame; Roseline Doe; Sarpong Ntiamoah; Samuel Oppong. Additional collaborators: Amos Apreku; Caroline Badzi; Maxwell Boakye Agyemang; Derrick Holdbrook; Alhassan Yakubu. Kenya: Beth Maina, Rosalin Ochieng. Additional collaborators: Tahera Khatau; Josephine Kizidio; Roy Moki; Bancy Ngatia; Barack Obara; Jasmit Shah. Pakistan : Sadia Aftab, Khalil Ahmad, Imran Ahmed, Naheed Akhter, Noreen Akmal, Talha Ali, Shabina Ariff, Sarwat Bukhari, Shireen Gul, Shamsa Humayun, Muhammad Riaz Hussain, Saba Khan, Zohra Khanum, Erum Majid, Shazia Masheer, Salman Muhammad, Shamila Ijaz Munir, Amtul Quddos, Rehana Rahim, Syeda K Riaz, Ahmareen K Sheikh, Lumaan Sheikh, Summaya Sohail, Shahid Tanveer, Shahida Tasneem, Zeeshan Uddin, Massab Umair, Shagufta Yasmeen, Haleema Yasmin, Afia Zafar, Farnaz Zahoor, Leila Zeb. Additional collaborators: Saira Afghan; Khadija Bano; Zaheer Habib; Aisha Malik; Syeda B Mazhar; Sayyeda Reza; Sana Yusuf. Philippines : Maria Stephanie Fay S. Cagayan; Francisco M. Heralde; Paulyn Jean B. Rosell-Ubial; Maria Esterlita V. Yu. Additional collaborators: Maria Lu D. Andal; Julia B. Beltran; Charizze Anne S. Cabana; Ryan B. Capitulo; Malaya M. Capulong; Leilani C. Chavez-Coloma; Vanessa D. De Guzman; Arlene R. Dominguez; ; Carolina Paula C. Martin; Amalea D. Nicolasora; Maricris D. Pacoli-Corduwa; Coney S. Pacua-Platero; Celine D. Quanico; Mary Abigail T. Roque; Merle D. Sacdalan-Faustino; Margarette Gale P. Santos; Maria Cecilia O. Tolentino; Cynthia L. Ubaldo-Anzures; Eleyneth I. Valencia; Daniel C. Villarico. Spain : Cristina Ruiz-Aguilar, Elia García-Verdevio. Additional collaborators: Reyes Balanza; Celia Barber-Almenar; Pilar Codoñer; Beatriz Mansilla-Roig; Alicia Martínez-Sebastián; María Navío Anaya; Vallivana Rodrigo-Casares. Tunisia: Nesrine Abderahmane; Youssef Atef; Emna Barkaoui; Med Bedis Channoufi; Majdi Ben Ameur; Rim Ben Hmid; Dalenda Chelli; Myriam Cheour; Hajer Chourou; Samia Kacem; Khaoula Magdoud; Hiba Mkadmi; Khaled Neji. Additional collaborators: Wajih Abidi; Tessnim Aissaoui; Amira Ammar; Jamel Ammar; Radhia Ammi; Monia Ardhaoui; Sonia Attia; Imen Ayari; Emna Barkaoui; Zeineb Belaiba; Sahar Belayeb; Besma Belgasmi; Wafa Belhaj Ammar; Samar Ben Hlima; Nadia Benameur; Achref Ben Messoud; Ameny Ben Rabiaa; Med Samir Boubaker; Wafa Chamsa; Asma Cherni; Riadh Daghfous; Ayhem Dahmeni; Hafedh Dakhlaoui; Sihem El Aidli; Cyrine El Fekih; Emna Fehri; Aymen Ferjaoui; Manel Gharbi; Walid Hammemi; Nahed Hogga; Leila Jabri; Zeineb Jarraya; Abir Jlassi; Maria Kabbage; Sana Kalthoum; Abir Karoui; Besma Khalledi; Chadha Khemissi; Henda Krichen; Hechmi Louzir; Mouna Maghrabi; Lamia Mannai; Zina Meddeb; Fethi Mraihi; Alaya Nabiha; Fatma Naffeti; Anissa Noury; Soumayya Ouhibi; Kaouther Ouerhani; Nadia Rahalai; Abir Rebhi; Khaoula Rezgui; Rihab Romdhane; Amel Sadraoui; Khaoula Samaali; Henda Touzi; Fatma Zgolli. Finally, we have listed below the contributing authors of the WHO COVID-19 Pregnancy Cohort Study group: WHO Coordinating Team (by descending order of contribution) : 1 Edna Kara § , Sami L Gottlieb § , Nathalie J Broutet , Anna Thorson, Marie Delnord, Ibukun-Oluwa Omolade Abejirinde. WHO Data Management and Analysis Team (by descending order of contribution) : 1 Ronaldo Silva £ , Soe Soe Thwin £ , Daniel Giordano, Ndema Abu Habib. Implementing Country Teams (by country and in alphabetical order) : Argentina 2 : Edgardo Abalos*. Brazil 3 : José G Cecatti*; Maria L Costa; Renato T Souza. Burkina Faso 4 : Seni Kouanda*; Desiré L. Dahourou; Henri Gautier Ouedraogo. Chile 5 : Sergio Munoz*; Gerardo Espinoza; Araceli Saavedra. Ghana 6 : Kwasi Torpey*; Chris Guure; Ernest Maya; Emefa Modey. Kenya : Marleen Temmerman 7 *; Rodney D. Adam 7 ; Ingrid Gichere 7 ; Sura Mandeep 8 . Pakistan 9 : Sarah Saleem*; Najia Ghanchi; Saleem Jessani. Philippines : Erlidia Llamas-Clark 10,11 *; Emmanuel S Baja 10 ; Mayan V Lumandas 12 . Spain 13 : Alejandro Orrico-Sánchez*; Antonio Carmona. Tunisia : Henda Triki 14 *; Mariem Gdoura 14,15 . Also see in the acknowledgements the full list of contributors in each country. *Principal Investigators § Lead authors £ Lead analyst/Statistician References Allotey J, Fernandez S, Bonet M, Stallings E, Yap M, Kew T, et al. Clinical manifestations, risk factors, and maternal and perinatal outcomes of coronavirus disease 2019 in pregnancy: living systematic review and meta-analysis. BMJ. 2020;370:m3320. doi:10.1136/bmj.m3320 Smith ER, Oakley E, Grandner GW, Perinatal COVID PMA Study Collaborators, et al. Adverse maternal, fetal, and newborn outcomes among pregnant women with SARS-CoV-2 infection: an individual participant data meta-analysis. BMJ Glob Health. 2023;8:e009495. Mupanomunda M, Fakih MG, Miller C, et al. Comparison of severe maternal morbidities associated with delivery during periods of circulation of specific SARS-CoV-2 variants. JAMA Netw Open. 2022;5(8):e2226436. doi:10.1001/jamanetworkopen.2022.26436 Villar J, Ariff S, Gunier RB, et al. Maternal and neonatal morbidity and mortality among pregnant women with and without COVID-19 infection: the INTERCOVID multinational cohort study. JAMA Pediatr. 2021;175(8):817–826. Banga J, Jackson-Gibson M, Diseko M, Caniglia EC, Mayondi G, Mabuta J, et al. No impact of COVID-19 at delivery on maternal mortality or infant adverse birth outcomes in Botswana during the Omicron era. PLoS One. 2024;19(9):e0310980. doi:10.1371/journal.pone.0310980 World Health Organization, UNICEF, UNFPA, World Bank Group, UNDESA/Population Division. Trends in maternal mortality estimates 2000 to 2023. Available from: https://www.who.int/publications/i/item/9789240108462 Generic protocol: a prospective cohort study investigating maternal, pregnancy and neonatal outcomes for women and neonates infected with SARS-CoV-2. 1 Nov 2022. American College of Obstetricians and Gynecologists. Committee Opinion: Methods for Estimating the Due Date. No. 700. May 2017. Shu Y, McCauley J. GISAID: global initiative on sharing all influenza data – from vision to reality. Euro Surveill. 2017;22. doi:10.2807/1560-7917.ES.2017.22.13.30494 World Health Organization. Caesarean section rates continue to rise, amid growing inequalities in access. Vogel JP, Lee AC, Souza JP. Maternal morbidity and preterm birth in 22 low- and middle-income countries: a secondary analysis of the WHO Global Survey dataset. BMC Pregnancy Childbirth. 2014;14:56. doi:10.1186/1471-2393-14-56 Holmer HK, Mackey K, Fiordalisi CV, Helfand M. Major Update 2: antibody response and risk for reinfection after SARS-CoV-2 infection—final update of a living, rapid review. Ann Intern Med. 2023;176(1):85–91. doi:10.7326/M22-1745 Sigal A. Milder disease with Omicron: is it the virus or the pre-existing immunity? Nat Rev Immunol. 2022;22:69–71. doi:10.1038/s41577-022-00678-4 Stock SJ, Moore E, Calvert C, Carruthers J, Denny C, Donaghy J, et al. Pregnancy outcomes after SARS-CoV-2 infection in periods dominated by Delta and Omicron variants in Scotland: a population-based cohort study. Lancet Respir Med. 2022;10(12):1129–1136. doi:10.1016/S2213-2600(22)00360-5 World Health Organization. WHO roadmap on uses of COVID-19 vaccines in the context of Omicron and high population immunity. Available from: https://iris.who.int/handle/10665/373987 Ciapponi A, Berrueta M, Argento FJ, Ballivian J, Bardach A, Brizuela ME, et al. Safety and effectiveness of COVID-19 vaccines during pregnancy: a living systematic review and meta-analysis. Drug Saf. 2024;47(10):991–1010. doi:10.1007/s40264-024-01458-w World Health Organization. WHO COVID-19 dashboard. Available from: https://data.who.int/dashboards/covid19/variants Feldstein LR, Ruffin J, Wiegand RE, Borkowf CB, James-Gist J, Babu TM, et al. Effectiveness of mRNA COVID-19 vaccines and hybrid immunity in preventing SARS-CoV-2 infection and symptomatic COVID-19 among adults in the United States. J Infect Dis. 2025;231(4):e743–e753. doi:10.1093/infdis/jiaf007 Table 1 Table 1 is available in the Supplementary Files section. Additional Declarations No competing interests reported. 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08:47:57","extension":"html","order_by":11,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":214453,"visible":true,"origin":"","legend":"","description":"","filename":"earlyproof.html","url":"https://assets-eu.researchsquare.com/files/rs-7933142/v1/187961cbe87462cb60634d6c.html"},{"id":96250228,"identity":"9fe2aeff-7612-4879-8aaf-4275fffc16d7","added_by":"auto","created_at":"2025-11-19 07:37:46","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":1967496,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eCategorizations based on likelihood of SARS-CoV-2 infection during pregnancy\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"Fig.1.png","url":"https://assets-eu.researchsquare.com/files/rs-7933142/v1/1e4eca2147654bdbe2c4e51b.png"},{"id":96160349,"identity":"40f011bb-1934-42d7-93c7-841235986e15","added_by":"auto","created_at":"2025-11-18 08:47:57","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":1912931,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eStudy flowchart and algorithm for determining infection status during pregnancy\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"Fig.2submission.png","url":"https://assets-eu.researchsquare.com/files/rs-7933142/v1/0d8f9f2fdd418e9d6c921fc5.png"},{"id":96256997,"identity":"a9cf422a-0dd0-402c-806b-4026c0c0a05e","added_by":"auto","created_at":"2025-11-19 07:51:13","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":7961655,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7933142/v1/f982bcab-dace-42d0-baff-9a3ef79c278e.pdf"},{"id":96160346,"identity":"8c47ecc9-9c67-4910-aa89-907455bb72a6","added_by":"auto","created_at":"2025-11-18 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08:47:57","extension":"docx","order_by":3,"title":"","display":"","copyAsset":false,"role":"supplement","size":22613,"visible":true,"origin":"","legend":"","description":"","filename":"Table1.docx","url":"https://assets-eu.researchsquare.com/files/rs-7933142/v1/93636de04fc2198252f13be8.docx"}],"financialInterests":"No competing interests reported.","formattedTitle":"Maternal, perinatal, neonatal, and postpartum outcomes following SARS-CoV-2 infection in pregnancy: A WHO multi-country prospective cohort study ","fulltext":[{"header":"Background","content":"\u003cp\u003eSince the emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), concerns about its effects on pregnancy have been raised worldwide. Systematic reviews and meta-analyses summarizing the effect of SARS-CoV-2 infection during pregnancy have demonstrated increased risk for multiple adverse maternal and perinatal outcomes [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. However, these meta-analyses have been limited by varying study designs, potentially inexact definitions of infection during pregnancy, and differing outcome definitions across included studies.\u003c/p\u003e\u003cp\u003eIn addition, most available data have been from earlier in the pandemic. Several studies have shown less severe maternal illness with Omicron variants, yet studies comparing pregnancy-related outcomes in infected and uninfected pregnant women during the Omicron and Omicron sub-variant era remain limited [\u003cspan additionalcitationids=\"CR4\" citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. Further, most data were from high-income countries (HICs). Less is known about the impact of infection on pregnancy in low- and middle-income countries (LMICs), where differences in access to higher-level care, underlying comorbidities, and baseline rates of adverse pregnancy outcomes might modify risks [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eEarly in the COVID-19 pandemic, the World Health Organization (WHO) developed a generic protocol for a prospective cohort study among pregnant women to facilitate systematic and harmonized data collection across different settings and to minimize potential biases. The study aimed to determine if SARS-CoV-2 infection during pregnancy increases the risk of adverse maternal, perinatal, neonatal, or postpartum outcomes. The protocol was implemented in 10 diverse, primarily LMICs (Argentina, Brazil, Burkina Faso, Chile, Ghana, Kenya, Pakistan, Philippines, Spain, and Tunisia). In this article, we report the pooled results of this study during pre-Omicron and Omicron periods of SARS-CoV-2 variant predominance. Additionally, we report on factors associated with SARS-CoV-2 illness severity, including vaccination, and the association of severity with adverse outcomes among infected women. Detailed evaluation of the effects of COVID-19 vaccination on pregnancy outcomes from this study will be reported separately.\u003c/p\u003e"},{"header":"Methods","content":"\u003cp\u003eThis prospective cohort study was conducted between January 2021 and November 2023, across 43 health facilities in the 10 countries (\u003cstrong\u003eAdditional File 1 -\u003c/strong\u003e Table 1\u003cstrong\u003e).\u003c/strong\u003e The study design, data collection, and reporting adhered to the STROBE (Strengthening the Reporting of Observational Studies in Epidemiology) guidelines to ensure transparency, completeness, and methodological rigor in the presentation of the research findings. The study protocol, including sample size estimation, is available online [7].\u003c/p\u003e\n\u003cdiv id=\"Sec3\"\u003e\n \u003ch2\u003eStudy procedures: enrolment\u003c/h2\u003e\n \u003cp\u003ePregnant or recently pregnant women (within 48 hours of delivery or end of pregnancy) attending antenatal care or other obstetric services at participating health facilities were consecutively recruited regardless of SARS-CoV-2 infection status or vaccination status. Only those unable to provide informed consent or assent or to attend follow-up visits were excluded.\u003c/p\u003e\n \u003cp\u003eAt enrolment, all participants had detailed assessment of demographics, past medical and obstetric history, gestational age, details of the current pregnancy including complications and comorbidities, and COVID-19 vaccination status, with review of the obstetric record up to the time of enrolment.\u003c/p\u003e\n \u003cp\u003eAt enrolment, all participants received virologic testing for SARS-CoV-2, either reverse transcription polymerase chain reaction (RT-PCR) or antigen testing depending on study site, regardless of symptoms, along with serologic testing for SARS-CoV-2 antibodies. Participants who had never received a COVID-19 vaccine were tested for antibodies against the spike (S) protein of SARS-CoV-2 (Wantai BioPharm SARS-CoV-2 Ab ELISA, China). Vaccinated participants underwent anti-nucleocapsid (N) protein serologic testing (BioRad Platelia SARS-CoV-2 Total Ab Assay, USA) to distinguish infection-induced (S+/N+) from vaccine-acquired antibodies (S+/N-). An exception applied to women who received inactivated whole virus vaccines, which induce production of both anti-S and anti-N antibodies. In these cases, serologic status remained unknown. COVID-19 vaccination status was confirmed using vaccination cards, medical records, or vaccination registries wherever possible. Participants were asked about COVID-19-related symptoms, diagnoses and treatments, and medical and laboratory records were reviewed for COVID-19 diagnoses during and prior to pregnancy.\u003c/p\u003e\n\u003c/div\u003e\n\u003ch3\u003eStudy procedures: follow-up\u003c/h3\u003e\n\u003cp\u003eFollow-up data were collected during regular antenatal care visits, which were typically every 4–6 weeks; however, intervals varied by country. Changes in health status, pregnancy complications, COVID-19 vaccination, COVID-19-related symptoms and laboratory findings since the previous visit were recorded, along with dates. At delivery, data were also collected on mode of delivery and pregnancy outcomes.\u003c/p\u003e\n\u003cp\u003eParticipants presenting with signs or symptoms related to COVID-19 at any time during follow-up received RT-PCR or antigen testing. In addition, all participants who had previous negative SARS-CoV-2 serologic testing at enrolment or follow-up had repeat serologic testing at subsequent follow-up visits including delivery.\u003c/p\u003e\n\u003cp\u003eParticipants were followed through six weeks after delivery, and information was collected on symptoms and health outcomes of both the woman and her neonate(s).\u003c/p\u003e\n\u003ch3\u003eDefinitions\u003c/h3\u003e\n\u003cdiv id=\"Sec6\"\u003e\n \u003ch2\u003eGestational age\u003c/h2\u003e\n \u003cp\u003eGestational age was estimated based on ultrasound measurement in the first trimester or on last menstrual period (LMP), where start of pregnancy (day 0) was the first day of LMP. If both measurements were available, the best obstetric estimate was used, based on the American College of Obstetricians and Gynecologists algorithm [8].\u003c/p\u003e\n \u003cp\u003eThe first trimester was defined as day 1–97 of pregnancy (week 0–13), second trimester day 98–195 (week 14–27), and third trimester day 196–280+ (week 28–40+).\u003c/p\u003e\n\u003c/div\u003e\n\u003ch3\u003eSARS-CoV-2 infection status\u003c/h3\u003e\n\u003cp\u003eWomen were grouped into six mutually exclusive exposure categories based on the likelihood that SARS-CoV-2 infection occurred during pregnancy: confirmed infected, probably infected, possibly infected, probably uninfected, confirmed uninfected, and unknown (\u003cstrong\u003eFig.\u0026nbsp;1\u003c/strong\u003e).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFigure\u0026nbsp;1. Categorizations based on likelihood of SARS-CoV-2 infection during pregnancy\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eParticipants were considered to have “confirmed” SARS-CoV-2 infection if they had a positive RT-PCR or Ag test result at any time during pregnancy or seroconversion (not related to vaccination) during follow-up. Those with consistently negative virologic and serologic test results were considered “confirmed uninfected”. Since a positive serologic test might reflect infection prior to pregnancy, most women with positive serology results were categorized as “possibly” infected during pregnancy, barring clinical diagnoses during pregnancy or known infection just prior to pregnancy. Participants whose infection status during pregnancy could not be determined because of missing data or prior receipt of inactivated vaccines were classified as “unknown”.\u003c/p\u003e\n\u003cp\u003eThe date of infection was defined as the date of specimen collection for positive RT-PCR and antigen tests, the midpoint between negative and positive serologic specimen collection for seroconversion, and first day of symptoms for clinical diagnosis. For those with infection, information was collected on symptoms and hospitalization. “Moderate” illness was defined as presence of fever, shortness of breath, or chest pain, while COVID-19-related hospital admission was used as a proxy for “severe” infection. Having at least one symptom but none in the moderate or severe category was defined as “mild” illness.\u003c/p\u003e\n\u003cdiv id=\"Sec8\"\u003e\n \u003ch2\u003eOutcomes\u003c/h2\u003e\n \u003cp\u003eStudy outcomes are outlined in \u003cstrong\u003eBox 1.\u003c/strong\u003e Detailed definitions are provided in \u003cstrong\u003eAdditional File 2 -\u003c/strong\u003e Table 2. All analyses incorporated restrictions to ensure temporal plausibility, i.e., outcomes occurring after COVID-19 test date.\u003c/p\u003e\n \u003ctable id=\"Tab2\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv\u003eTable 2\u003c/div\u003e\n \u003cdiv\u003e\n \u003cp\u003eMaternal, pregnancy, perinatal, neonatal and postpartum outcomes by SARS-CoV-2 infection status during pregnancy\u003csup\u003e¥\u003c/sup\u003e\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\" rowspan=\"2\"\u003e\n \u003cp\u003eOutcome\u003csup\u003e§\u003c/sup\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" rowspan=\"2\"\u003e\n \u003cp\u003eConfirmed or probably infected\u003csup\u003e£\u003c/sup\u003e\u003c/p\u003e\n \u003cp\u003eN = 2,305\u003csup\u003e\u003cem\u003e1\u003c/em\u003e\u003c/sup\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" rowspan=\"2\"\u003e\n \u003cp\u003eConfirmed or probably uninfected\u003csup\u003e£\u003c/sup\u003e\u003c/p\u003e\n \u003cp\u003eN = 1,455\u003csup\u003e\u003cem\u003e1\u003c/em\u003e\u003c/sup\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"3\"\u003e\n \u003cp\u003eAdjusted infected vs uninfected random-effects model\u003c/p\u003e\n \u003cp\u003eRR (95% CI); p-value\u003csup\u003e2\u003c/sup\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eOverall sample\u003c/p\u003e\n \u003cp\u003e(Events / Total)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eRestricted to\u003c/p\u003e\n \u003cp\u003epre-Omicron\u003c/p\u003e\n \u003cp\u003e(Events / Total)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eRestricted to Omicron\u003c/p\u003e\n \u003cp\u003e(Events/Total)\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003cth align=\"left\" colspan=\"6\"\u003e\n \u003cp\u003eMATERNAL AND PREGNANCY OUTCOMES\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colspan=\"3\"\u003e\n \u003cp\u003e\u003cstrong\u003eMiscarriage (before 22 weeks GA)*\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e16/401\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e6/212\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e10/189\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e11 (3.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e5 (4.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e0.71 (0.47,1.08)\u003c/p\u003e\n \u003cp\u003ep = 0.1079\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e0.99 (0.28,3.49)\u003c/p\u003e\n \u003cp\u003ep = 0.9838\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e0.76 (0.53,1.10)\u003c/p\u003e\n \u003cp\u003ep = 0.1447\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e290 (96.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e97 (05.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eAt risk\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e301\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e102\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colspan=\"3\"\u003e\n \u003cp\u003e\u003cstrong\u003eMiscarriage (before 28 weeks GA) *\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e16/403\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e6/213\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e10/190\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e11 (3.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e5 (4.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e0.71 (0.47,1.07)\u003c/p\u003e\n \u003cp\u003ep = 0.1049\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e0.98 (0.28,3.45)\u003c/p\u003e\n \u003cp\u003ep = (0.9777)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e0.76 (0.53,1.10)\u003c/p\u003e\n \u003cp\u003ep = 0.1426\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e292 (96.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e97 (95.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eAt risk\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e303\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e102\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colspan=\"3\"\u003e\n \u003cp\u003e\u003cstrong\u003eHaemorrhage (antepartum, intrapartum, or immediately postpartum)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e116/3,565\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e92/2,949\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e24/616\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e80 (3.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e37 (2.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e1.59 (0.65,3.88)\u003c/p\u003e\n \u003cp\u003ep = 0.3057\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e2.02 (0.95,4.29)\u003c/p\u003e\n \u003cp\u003ep = 0.0677\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e0.51 (0.23,1.11)\u003c/p\u003e\n \u003cp\u003ep = 0.0894\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2,126 (96.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,339 (97.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eAt risk\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2,206\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,376\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colspan=\"3\"\u003e\n \u003cp\u003e\u003cstrong\u003ePreeclampsia/eclampsia\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e240/3,607\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e185/2973\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e55/634\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e156 (7.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e84 (6.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e1.32 (0.76,2.31)\u003c/p\u003e\n \u003cp\u003ep = 0.3293\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e1.46 (0.78,2.74)\u003c/p\u003e\n \u003cp\u003ep = 0.2338\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e0.93 (0.63,1.37)\u003c/p\u003e\n \u003cp\u003ep = 0.7044\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2,087 (93.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,305 (93.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eAt risk\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2,243\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,389\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colspan=\"3\"\u003e\n \u003cp\u003e\u003cstrong\u003eHypertensive disorders of pregnancy\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e327/3,608\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e244/2,974\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e83/634\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e218 (9.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e109 (7.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e1.38 (0.83,2.31)\u003c/p\u003e\n \u003cp\u003ep = 0.2153\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e1.59 (0.94,2.68)\u003c/p\u003e\n \u003cp\u003ep = 0.0830\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e0.93 (0.59,1.47)\u003c/p\u003e\n \u003cp\u003ep = 0.7641\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2,026 (90.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,280 (92.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eAt risk\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2,244\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,389\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colspan=\"3\"\u003e\n \u003cp\u003e\u003cstrong\u003eThromboembolic disease\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e7/3,607\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e7/2,973\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e0/634\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4 (0.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3 (0.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e0.85 (0.21,3.35)\u003c/p\u003e\n \u003cp\u003ep = 0.8120\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e0.90 (0.23,3.58)\u003c/p\u003e\n \u003cp\u003ep = 0.8813\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e—\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2,238 (99.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,385 (99.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eAt risk\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2,242\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,388\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colspan=\"3\"\u003e\n \u003cp\u003e\u003cstrong\u003ePreterm labour\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e179/2,356\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e132/1,856\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e47/500\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e119 (7.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e60 (7.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e0.91 (0.68,1.22)\u003c/p\u003e\n \u003cp\u003ep = 0.5259\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e0.80 (0.59,1.09)\u003c/p\u003e\n \u003cp\u003ep = 0.1542\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e1.27 (0.74,2.17)\u003c/p\u003e\n \u003cp\u003ep = 0.3831\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,459 (92.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e731 (92.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eAt risk\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,578\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e791\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colspan=\"3\"\u003e\n \u003cp\u003e\u003cstrong\u003ePlacental abruption\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e17/3,607\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e14/2,973\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e3/634\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e10 (0.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e7 (0.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e0.93 (0.39,2.24)\u003c/p\u003e\n \u003cp\u003ep = 0.8716\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e0.91 (0.36,2.33)\u003c/p\u003e\n \u003cp\u003ep = 0.8475\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e0.84 (0.25,2.80)\u003c/p\u003e\n \u003cp\u003ep = 0.7732\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2,232 (99.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,381 (99.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eAt risk\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2,242\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,388\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colspan=\"3\"\u003e\n \u003cp\u003e\u003cstrong\u003eMaternal near-miss at delivery\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e65/3534\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e58/2910\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e7/624\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e36 (1.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e29 (2.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e1.16 (0.60,2.25)\u003c/p\u003e\n \u003cp\u003ep = 0.6639\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e1.28 (0.68,2.40)\u003c/p\u003e\n \u003cp\u003ep = 0.4489\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e0.59 (0.12,2.86)\u003c/p\u003e\n \u003cp\u003ep = 0.5083\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2145 (98.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1343 (97.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eAt risk\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2,181\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,372\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colspan=\"3\"\u003e\n \u003cp\u003e\u003cstrong\u003eC-section\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e767/3,552\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e636/2,938\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e131/614\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eEmergency\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e507 (23.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e265 (19.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e1.16 (0.93,1.46)\u003c/p\u003e\n \u003cp\u003ep = 0.1903\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e1.26 (1.03,1.53)\u003c/p\u003e\n \u003cp\u003ep = 0.0270\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e0.73 (0.56,0.95)\u003c/p\u003e\n \u003cp\u003ep = 0.0181\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eOther delivery modes\u003csup\u003eα\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,695 (77.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,105 (80.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eAt risk\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2,202\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,370\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colspan=\"3\"\u003e\n \u003cp\u003e\u003cstrong\u003eMaternal death\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e9/3,603\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e7/2,969\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e2/634\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e8 (0.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1 (0.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e3.45 (0.93,12.78)\u003c/p\u003e\n \u003cp\u003ep = 0.0640\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e3.15 (0.74,13.40)\u003c/p\u003e\n \u003cp\u003ep = 0.1206\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e—\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2,232 (99.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,387 (99.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eAt risk\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2,240\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,388\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colspan=\"3\"\u003e\n \u003cp\u003e\u003cstrong\u003eModified maternal morbidity and mortality index (MMMI)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e749/3,560\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e575/2,930\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e174/630\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e467 (21.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e283 (20.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e1.13 (0.94,1.37)\u003c/p\u003e\n \u003cp\u003ep = 0.1931\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e1.27 (1.12,1.44)\u003c/p\u003e\n \u003cp\u003ep = 0.0001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e0.76 (0.48,1.22)\u003c/p\u003e\n \u003cp\u003ep = 0.2585\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,741 (78.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,093 (79.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eAt risk\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2,208\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,376\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colspan=\"6\"\u003e\n \u003cp\u003e\u003cstrong\u003ePERINATAL AND NEONATAL OUTCOMES\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colspan=\"3\"\u003e\n \u003cp\u003e\u003cstrong\u003eStillbirth at/after 22 weeks GA\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e21/3,575\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e19/2,958\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e2/617\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e15 (0.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e7 (0.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e1.36 (0.51, 3.58)\u003c/p\u003e\n \u003cp\u003ep = 0.5392\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e1.25 (0.46,3.38)\u003c/p\u003e\n \u003cp\u003ep = 0.6568\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e—\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2,205 (99.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,374 (99.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eAt risk\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2,220\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,381\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colspan=\"3\"\u003e\n \u003cp\u003e\u003cstrong\u003eStillbirth at/after 28 weeks GA\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e20/3,560\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e18/2,945\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e2/615\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e14 (0.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e7 (0.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e1.23 (0.47,3.23)\u003c/p\u003e\n \u003cp\u003ep = 0.6704\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e1.11 (0.42,2.93)\u003c/p\u003e\n \u003cp\u003ep = 0.8356\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e—\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2,192 (99.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,373 (99.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eAt risk\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2,206\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,380\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colspan=\"3\"\u003e\n \u003cp\u003e\u003cstrong\u003ePreterm birth (\u0026lt; 37 weeks)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e541/2,904\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e423/2,381\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e118/523\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e362 (23.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e181 (13.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e1.53 (1.27,1.84)\u003c/p\u003e\n \u003cp\u003ep = \u0026lt; 0.0001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e1.73 (1.32,2.28)\u003c/p\u003e\n \u003cp\u003ep = 0.0001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e1.03 (0.68,1.57)\u003c/p\u003e\n \u003cp\u003ep = 0.8812\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,181 (76.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,192 (86.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eAt risk\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,543\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,373\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colspan=\"3\"\u003e\n \u003cp\u003e\u003cstrong\u003ePreterm birth (\u0026lt; 34 weeks)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e120/2,656\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e93/2,163\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e27/493\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e95 (7.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e26 (1.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e3.01 (1.74,5.21)\u003c/p\u003e\n \u003cp\u003ep = 0.0001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e3.69 (1.92,7.09)\u003c/p\u003e\n \u003cp\u003ep = 0.0001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e1.88 (1.04,3.39)\u003c/p\u003e\n \u003cp\u003ep = 0.0366\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,196 (92.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,347 (98.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eAt risk\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,291\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,373\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colspan=\"3\"\u003e\n \u003cp\u003e\u003cstrong\u003ePreterm birth (\u0026lt; 32 weeks)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e58/2,540\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e43/2,062\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e15/478\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e50 (4.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e9 (0.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e4.59 (1.51,13.94)\u003c/p\u003e\n \u003cp\u003ep = 0.0072\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e7.58 (2.19,26.19)\u003c/p\u003e\n \u003cp\u003ep = 0.0014\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e1.88 (0.55,6.44)\u003c/p\u003e\n \u003cp\u003ep = 0.3164\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,124 (95.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,364 (99.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eAt risk\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,174\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,373\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colspan=\"3\"\u003e\n \u003cp\u003e\u003cstrong\u003eLow birth weight (\u0026lt; 2,500g)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e455/3,197\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e370/2,625\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e85/572\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e287 (15.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e171 (13.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e1.16 (0.93, 1.45)\u003c/p\u003e\n \u003cp\u003ep = 0.1817\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e1.20 (0.95,1.51)\u003c/p\u003e\n \u003cp\u003ep = 0.1201\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e0.97 (0.68,1.37)\u003c/p\u003e\n \u003cp\u003ep = 0.8501\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,608 (84.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,141 (87.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eAt risk\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,895\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,312\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colspan=\"3\"\u003e\n \u003cp\u003e\u003cstrong\u003eVery low birth weight (\u0026lt; 1,500g)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e88/3,197\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e76/2,625\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e12/572\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e51 (2.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e38 (2.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e1.10 (0.52,2.31)\u003c/p\u003e\n \u003cp\u003ep = 0.8022\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e1.19 (0.50,2.82)\u003c/p\u003e\n \u003cp\u003ep = 0.6930\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e0.89 (0.37,2.18)\u003c/p\u003e\n \u003cp\u003ep = 0.8018\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,844 (97.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,274 (97.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eAt risk\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,895\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,312\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colspan=\"3\"\u003e\n \u003cp\u003e\u003cstrong\u003eCongenital anomaly (at or after 22 weeks)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e87/2,755\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e76/2,346\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e11/409\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e63 (3.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e24 (2.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e2.07 (0.94,4.53)\u003c/p\u003e\n \u003cp\u003ep = 0.0694\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e2.28 (0.80,6.46)\u003c/p\u003e\n \u003cp\u003ep = 0.1214\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e0.76 (0.39,1.49)\u003c/p\u003e\n \u003cp\u003ep = 0.4297\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,647 (96.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,032 (97.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eAt risk\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,710\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,056\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colspan=\"3\"\u003e\n \u003cp\u003e\u003cstrong\u003eCongenital anomaly (at or after 28 weeks)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e83/2,743\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e73/2,336\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e10/407\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e59 (3.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e24 (2.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e1.91 (0.95,3.85)\u003c/p\u003e\n \u003cp\u003ep = 0.0716\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e2.11 (0.83,5.35)\u003c/p\u003e\n \u003cp\u003ep = 0.1151\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e0.75 (0.42,1.34)\u003c/p\u003e\n \u003cp\u003ep = 0.3329\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,639 (96.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,032 (97.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eAt risk\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,698\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,056\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colspan=\"3\"\u003e\n \u003cp\u003e\u003cstrong\u003ePerinatal death (22-week stillbirths + early neonatal deaths)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e41/3,575\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e38/2,958\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e3/617\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e27 (1.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e15 (1.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e1.25 (0.77,2.01)\u003c/p\u003e\n \u003cp\u003ep = 0.3702\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e1.37 (0.85,2.19)\u003c/p\u003e\n \u003cp\u003ep = 0.1923\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e0.89 (0.27,2.99)\u003c/p\u003e\n \u003cp\u003ep = 0.8559\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2,193 (98.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,366 (98.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eAt risk\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.220\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,381\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colspan=\"3\"\u003e\n \u003cp\u003e\u003cstrong\u003ePerinatal death (28-week stillbirths + early neonatal deaths)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e37/3,560\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e34/2,945\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e3/615\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e24 (1.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e14 (1.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e1.20 (0.78,1.85)\u003c/p\u003e\n \u003cp\u003ep = 0.3980\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e1.32 (0.88,2.0)\u003c/p\u003e\n \u003cp\u003ep = 0.1850\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e0.90 (0.27,3.01)\u003c/p\u003e\n \u003cp\u003ep = 0.8617\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2,182 (98.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,366 (99.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eAt risk\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2,206\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,380\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colspan=\"3\"\u003e\n \u003cp\u003e\u003cstrong\u003eNeonatal/infant death\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e32/3,511\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e30/2,898\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e2/613\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e20 (0.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e13 (1.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e0.92 (0.26,3.32)\u003c/p\u003e\n \u003cp\u003ep = 0.9017\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e1.16 (0.38,3.54)\u003c/p\u003e\n \u003cp\u003ep = 0.7992\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e—\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2,154 (99.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,346 (99.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eAt risk\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2,174\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,359\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colspan=\"3\"\u003e\n \u003cp\u003e\u003cstrong\u003eNICU admission\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e468/3,497\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e383/2,886\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e85/611\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e321 (14.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e150 (11.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e1.63 (1.06,2.50)\u003c/p\u003e\n \u003cp\u003ep = 0.0267\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e1.90 (1.28,2.82)\u003c/p\u003e\n \u003cp\u003ep = 0.0015\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e0.82 (0.54,1.26)\u003c/p\u003e\n \u003cp\u003ep = 0.3748\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,842 (85.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,206 (88.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eAt risk\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2,163\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,356\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colspan=\"3\"\u003e\n \u003cp\u003e\u003cstrong\u003eSPMMI\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e281/3,504\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e230/2,900\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e51/604\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e196 (9.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e89 (6.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e1.57 (0.97,2.54)\u003c/p\u003e\n \u003cp\u003ep = 0.0685\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e1.76 (1.01,3.05)\u003c/p\u003e\n \u003cp\u003ep = 0.0449\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e0.86 (0.45,1.63)\u003c/p\u003e\n \u003cp\u003ep = 0.6374\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,969 (91.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,273 (93.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eAt risk\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2,165\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,362\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colspan=\"6\"\u003e\n \u003cp\u003e\u003cstrong\u003ePOSTPARTUM OUTCOMES\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colspan=\"3\"\u003e\n \u003cp\u003e\u003cstrong\u003ePostpartum haemorrhage\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e30/3,359\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e26/2,758\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e4/601\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e12 (0.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e18 (1.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e0.51 (0.24,1.08)\u003c/p\u003e\n \u003cp\u003ep = 0.0795\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e0.39 (0.18,0.84)\u003c/p\u003e\n \u003cp\u003ep = 0.0158\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e—\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2,062 (99.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,291 (98.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eAt risk\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2,074\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,309\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colspan=\"3\"\u003e\n \u003cp\u003e\u003cstrong\u003ePostpartum complications: Maternal infection or endometritis\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e77/3,334\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e57/2,747\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e20/587\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e53 (2.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e25 (1.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e1.35 (1.04,1.74)\u003c/p\u003e\n \u003cp\u003ep = 0.0243\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e1.39 (0.94,2.06)\u003c/p\u003e\n \u003cp\u003ep = 0.0956\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e1.22 (0.73,2.04)\u003c/p\u003e\n \u003cp\u003ep = 0.4561\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2,000 (97.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,278 (98.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eAt risk\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2,053\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,303\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colspan=\"3\"\u003e\n \u003cp\u003e\u003cstrong\u003eAny readmission in the postpartum period\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e56/3,350\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e44/2,761\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e12/589\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e35 (1.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e21 (1.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e1.12 (0.70,1.79)\u003c/p\u003e\n \u003cp\u003ep = 0.6421\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e1.01 (0.58,1.78)\u003c/p\u003e\n \u003cp\u003ep = 0.9677\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003e1.71 (0.42,6.93)\u003c/p\u003e\n \u003cp\u003ep = 0.4524\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2,033 (98.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,283 (98.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eAt risk\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2,068\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1,304\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colspan=\"6\"\u003e\n \u003cp\u003e\u003csup\u003e\u003cem\u003e1\u003c/em\u003e\u003c/sup\u003e n (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colspan=\"6\"\u003e\n \u003cp\u003e\u003csup\u003e\u003cem\u003e2\u003c/em\u003e\u003c/sup\u003e Pearson’s Chi-squared test\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003ctfoot\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"6\"\u003e*Denominator: All completed pregnancies enrolled at \u0026lt; 20 weeks of gestation\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"6\"\u003e\u003csup\u003e¥\u003c/sup\u003e N appears at multiple rows to reflect change in the denominator due to difference in outcome definitions\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"6\"\u003e§ M/U = Missing or Unknown\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"6\"\u003e£ N (%)\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"6\"\u003eα: other delivery modes include spontaneous vaginal delivery, instrumental delivery, and planned cesarean section.\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"6\"\u003eSome outcomes could not be evaluated because of small numbers or lack of model convergence.\u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tfoot\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003ch3\u003eBox 1. Study outcomes\u003c/h3\u003e\n\u003cdiv\u003e\n \u003ctable id=\"Taba\" border=\"1\"\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eMaternal and pregnancy\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eMiscarriage before 22 completed weeks of gestation; miscarriage before 28 weeks of gestation\u003c/p\u003e\n \u003cp\u003eHaemorrhage (antenatal, intrapartum and immediately postpartum)\u003c/p\u003e\n \u003cp\u003ePreeclampsia or eclampsia\u003c/p\u003e\n \u003cp\u003eHypertensive disorders of pregnancy\u003c/p\u003e\n \u003cp\u003eThromboembolic disease\u003c/p\u003e\n \u003cp\u003ePreterm labour (\u0026lt; 37 weeks)\u003c/p\u003e\n \u003cp\u003ePlacental abruption\u003c/p\u003e\n \u003cp\u003eMaternal near-miss indicators at delivery\u003c/p\u003e\n \u003cp\u003eCaesarean section\u003c/p\u003e\n \u003cp\u003eMaternal death (during pregnancy or until 42 days postpartum)\u003c/p\u003e\n \u003cp\u003eModified maternal morbidity and mortality index (MMMI): at least 1 of the following: haemorrhage at labour and delivery, hypertensive disorders of pregnancy (including preeclampsia/eclampsia), thromboembolic disease, preterm labour, placental abruption; OR near-miss indicator at delivery; OR death.\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePerinatal and neonatal\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eStillbirth at or after 22 completed weeks of gestation; stillbirth at or after 28 weeks of gestation\u003c/p\u003e\n \u003cp\u003ePreterm birth \u0026lt; 37 weeks; preterm birth \u0026lt; 34 weeks; preterm birth \u0026lt; 32 weeks\u003c/p\u003e\n \u003cp\u003eLow birth weight (\u0026lt; 2500g); very low birth weight (\u0026lt; 1500g)\u003c/p\u003e\n \u003cp\u003eCongenital anomaly (at or after 22 weeks; at or after 28 weeks)\u003c/p\u003e\n \u003cp\u003ePerinatal death (from 22 weeks gestation to 7 days after birth; from 28 weeks gestation to 7 days after birth)\u003c/p\u003e\n \u003cp\u003eNeonatal death (up to 28 days after birth)\u003c/p\u003e\n \u003cp\u003eNeonatal intensive care unit (NICU) admission\u003c/p\u003e\n \u003cp\u003eSevere perinatal morbidity and mortality index (SPMMI): either stillbirth; OR at least one of the following: hypoxic-ischemic encephalopathy, sepsis; OR admission to the NICU for 7 days or longer; OR neonatal death before hospital discharge.\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePostpartum\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePostpartum haemorrhage\u003c/p\u003e\n \u003cp\u003eInfection or endometritis\u003c/p\u003e\n \u003cp\u003eReadmission to the hospital during the postpartum period\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cp\u003e\u003cstrong\u003eTable 3.\u003c/strong\u003e\u003cstrong\u003e\u0026nbsp;Regression model to determine factors associated with severity of illness among SARS-CoV-2 infected women\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"3\"\u003e\n \u003cp\u003e\u003cstrong\u003eCovariates in the model\u003c/strong\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"bottom\"\u003e\n \u003cp\u003e\u003cstrong\u003eSummary Statistics by Symptoms\u003c/strong\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"bottom\"\u003e\n \u003cp\u003e\u003cstrong\u003eOdds Ratio of Moderate or Severe Symptoms\u003c/strong\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e\u003cstrong\u003eAsymptomatic or Mild\u003c/strong\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003e\u003cstrong\u003eModerate or Severe\u003c/strong\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" valign=\"bottom\"\u003e\n \u003cp\u003e\u003cstrong\u003eOdds Ratio OR 95% CI\u003c/strong\u003e\u003csup\u003e1,\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" valign=\"bottom\"\u003e\n \u003cp\u003e\u003cstrong\u003ep-value\u003c/strong\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003eN = 1,939\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\"\u003e\n \u003cp\u003eN = 323\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"5\"\u003e\n \u003cp\u003e\u003cstrong\u003eMaternal age at enrollment (years)\u003c/strong\u003e \u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Median [Q1, Q3]\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;30 [26,35]\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; 31 [27,35]\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e1.06 (0.93,1.22)\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.374\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Missing/Unknown\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e19\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"5\"\u003e\n \u003cp\u003e\u003cstrong\u003ePresence of medical conditions\u003c/strong\u003e \u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; 0\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e953 (88.9%)\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e119 (11.1%)\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e—\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; 1 or more conditions\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e930 (82.4%)\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e199 (17.6%)\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e1.27 (0.97,1.66)\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.088\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Missing/Unknown\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e56\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003eVaccination status\u003c/strong\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Never vaccinated\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e615 (82.6%)\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e130 (17.4%)\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e—\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Partially vaccinated\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e147 (86.0%)\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e24 (14.0%)\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.62 (0.38,1.01)\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.056\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Fully vaccinated, last dose before pregnancy\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e419 (86.7%)\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e64 (13.3%)\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.84 (0.57,1.24)\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.384\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Fully vaccinated, last dose during pregnancy\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e591 (86.8%)\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e90 (13.2%)\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.47 (0.47,1.02)\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.063\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Missing/Unknown\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e167\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e15\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003eVariant of concern\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; pre-Omicron\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e1,549 (84.5%)\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e285 (15.5%)\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e—\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Omicron\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e390 (91.1%)\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e38 (8.9%)\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.52 (0.34,0.78)\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.002\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u0026nbsp;\u003csup\u003e1\u0026nbsp;\u003c/sup\u003eOdds Ratios determine association after adjusting for other covariates in the model.\u003c/p\u003e\n\u003cp\u003e£: Maternal age OR per 5-year increase\u003c/p\u003e\n\u003ch3\u003eVariant period\u003c/h3\u003e\n\u003cp\u003eVariant of concern (VOC) designation was determined based on country-specific genetic sequencing data from the Global Initiative on Sharing All Influenza Data (GISAID), which had been expanded to include SARS-CoV-2 data [9]. The assigned VOC was the variant predominant in 75% or more cases in the participant’s country at the pregnancy start date. Participants with an Omicron VOC designation were classified as 'Omicron' and those with any other VOC designation were grouped under 'pre-Omicron'.\u003c/p\u003e\n\u003cdiv id=\"Sec11\"\u003e\n \u003ch2\u003eVaccination status\u003c/h2\u003e\n \u003cp\u003eParticipants were considered fully vaccinated if they had received a complete primary series (at least one dose for J\u0026amp;J/Janssen or CanSino and at least two doses for all other vaccines); partially vaccinated if they had only received one dose (aside from J\u0026amp;J/Janssen or CanSino); and never vaccinated if they had not received any doses. The “fully vaccinated” group was divided according to whether their most recent dose was during or before pregnancy.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec12\"\u003e\n \u003ch2\u003eData management\u003c/h2\u003e\n \u003cp\u003eData were collected using paper-based or tablet-based case report forms and subsequently key-entered into a validated web-interface electronic data capture system on the OpenClinica® platform (OpenClinica LLC, Waltham, Massachusetts, USA). Country-specific user accounts were password-protected, with a hierarchy of data access depending on each researcher’s role. Data sent to the server were encrypted using Secure Hash Algorithm 256-bit (SHA256) with Rivest-Shamir-Adleman (RSA) encryption. All study records were anonymised with unique study numbers. A standardised data management plan for data collection, curation, and discrepancy management was coordinated by WHO through web-based dashboards and periodic PDF reports.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec13\"\u003e\n \u003ch2\u003eStatistical analysis\u003c/h2\u003e\n \u003cp\u003eParticipants with unknown infection status were excluded from both primary and sensitivity analyses. Characteristics of enrolled participants including country, demographics, clinical and obstetric history, SARS-CoV-2 infection status during pregnancy, and VOC designation were summarized using appropriate descriptive statistics. Categorical variables were presented as proportions, while continuous variables were summarized using measures of central tendency (mean or median) and dispersion (standard deviation or quartiles), based on variable distribution. Comparisons of proportions were conducted using Pearson’s chi-squared test or Fisher’s exact test, and comparisons of continuous variables were conducted using the Wilcoxon rank sum test. A p-value \u0026lt; 0.05 was considered statistically significant.\u003c/p\u003e\n \u003cp\u003eFor the primary analysis, participants with confirmed or probable SARS-CoV-2 infection during pregnancy were considered as “SARS-CoV-2 infected”, and those with confirmed or probably no infection during pregnancy were considered as “uninfected” (\u003cstrong\u003eFig.\u0026nbsp;1\u003c/strong\u003e). Risk of adverse pregnancy outcomes related to SARS-CoV-2 infection during pregnancy were evaluated by comparing the absolute risk of outcomes in the infected group to the uninfected group and by estimating the relative risk (RR) using log-binomial generalized linear mixed models (GLMMs). We reviewed forest plots by country for each outcome and stratified by VOC period to identify countries with extreme RRs or disproportionately large influence on pooled estimates. Models were refitted, excluding these countries, and evaluated for consistency. Country-specific random intercepts were used to account for potential clustering.\u003c/p\u003e\n \u003cp\u003eAll models were adjusted for maternal age at enrollment and presence of at least one comorbidity. Modification of effects by VOC was evaluated by fitting the model with an interaction term between SARS-CoV-2 infection and VOC period, and RR estimates were reported for combined sample and stratified for the pre-Omicron and Omicron periods. For all estimates, 95% confidence intervals (CI) were provided.\u003c/p\u003e\n \u003cp\u003eIn sensitivity analyses, these models were repeated twice: first by adding the “possibly infected during pregnancy” group to the \"infected” group and second, by adding the “possibly infected” group to the “uninfected” group.\u003c/p\u003e\n \u003cp\u003eFor each adverse pregnancy outcome of interest, denominators were established based on contribution to the gestational period at risk and timing of enrolment in the study, as some outcomes such as miscarriage occur only within specific time periods \u003cstrong\u003e(Additional File 2 -\u003c/strong\u003e Table\u0026nbsp;2). Those lost to follow up prior to completion of pregnancy and those whose SARS-CoV-2 testing occurred more than 48 hours after delivery were excluded. For preterm birth, an additional subgroup analysis was conducted. In the main analysis, the sample was restricted to participants with positive SARS-CoV-2 tests occurring prior to the gestation week for the preterm birth outcome being considered, but otherwise included all live births. For the subgroup analyses, further restrictions were applied: only participants with 1) enrollment dates, or 2) negative SARS-CoV-2 testing dates, prior to the gestation week were considered ensuring temporal alignment between infection status and outcome risk.\u003c/p\u003e\n \u003cp\u003eTo explore determinants of illness severity within the SARS-CoV-2 infected subgroup, a mixed effects logistic regression model, using country-specific random intercepts, was fitted to evaluate the association between maternal age, underlying conditions, vaccination status and VOC period with illness severity. Odds ratios (ORs) for moderate or severe illness compared to asymptomatic or mild infection and 95% CI were estimated. The risk of pregnancy, perinatal, and neonatal outcomes in the moderate or severe illness group relative to the asymptomatic or mild group, controlling for maternal age and presence of underlying conditions were assessed using the GLMM model as above.\u003c/p\u003e\n \u003cp\u003eAnalyses were conducted using R version 4.4.2 (R Foundation for Statistical Computing, Vienna, Austria).\u003c/p\u003e\n\u003c/div\u003e"},{"header":"Results","content":"\u003cdiv id=\"Sec15\" class=\"Section2\"\u003e\n \u003ch2\u003eStudy population\u003c/h2\u003e\n \u003cp\u003eOf 22,047 pregnant women screened at 43 facilities in 10 countries, 16,007 (72.6%) were enrolled. Study flow, assignment to infection status groups, and final analytic samples are shown in \u003cstrong\u003eFig.\u0026nbsp;2.\u003c/strong\u003e\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec16\" class=\"Section2\"\u003e\n \u003ch2\u003eFigure\u0026nbsp;2. Study flowchart and algorithm for determining infection status during pregnancy\u003c/h2\u003e\n \u003cp\u003eBased on laboratory testing and clinical diagnoses over the study, 2,189 (13.7%) participants were classified as having confirmed SARS-CoV2 infection during pregnancy, 116 (0.7%) had probable infection, 7,332 (45.8%) had possible infection, 402 (2.5%) probably had no infection, 1,053 (6.6%) had confirmed no infection during pregnancy, and 4,915 had unknown infection status.\u003c/p\u003e\n \u003cp\u003eThe distribution of participants by SARS-CoV-2 infection status across the participating countries is presented in \u003cstrong\u003eAdditional File 3 -\u003c/strong\u003e Table \u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003e. Most enrolled participants began their pregnancies in 2021 or 2022 (\u003cstrong\u003eAdditional File 4 - Fig.\u0026nbsp;1\u003c/strong\u003e). Of 15,914 with available data, 11,847 pregnancies (74.4%) began before the period of Omicron predominance (pre-Omicron) and 4,067 (25.6%) began during the period of Omicron predominance (\u003cstrong\u003eAdditional File 5 - Fig.\u0026nbsp;2\u003c/strong\u003e). Most infections (80.8%) also occurred in the pre-Omicron period.\u003c/p\u003e\n \u003cp\u003eWomen infected with SARS-CoV-2 during pregnancy were more likely than uninfected women to be multigravida (73.4% vs 69.0%, p\u0026thinsp;\u0026lt;\u0026thinsp;0.004), single or previously married (24.3% vs 13.5%, p\u0026thinsp;\u0026lt;\u0026thinsp;0.001), to have higher education (41.8% vs 36.6%, p\u0026thinsp;\u0026lt;\u0026thinsp;0.001), and to be unemployed or working in informal jobs (57.9% vs 45.0%, p\u0026thinsp;\u0026lt;\u0026thinsp;0.001) (Table \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e). Both groups were similar with respect to age at enrollment and alcohol consumption. Although the median gestational age at enrollment was 36 weeks for both groups, a higher proportion of infected women were enrolled earlier in pregnancy (6.4% vs 4.3% before 14 weeks, 22.0% vs 10.7% between 14\u0026ndash;27 weeks, 71.6% vs 85.0% after 27 weeks, p\u0026thinsp;\u0026lt;\u0026thinsp;0.001). Most study participants were seen in tertiary care hospitals, more commonly among those with infection (94.7% vs 80.4%, p\u0026thinsp;\u0026lt;\u0026thinsp;0.001).\u003c/p\u003e\n \u003cp\u003eConditions such as heart disease, lung disease, hypertension, and diabetes were consistently more prevalent in the infected group; however, these differences were not statistically significant \u003cstrong\u003e(Additional File 6 - Table\u0026nbsp;4)\u003c/strong\u003e. Additionally, considering the overall number of pre-existing conditions, the infected group was less likely to report one medical condition (41.2% vs 48.8%) and only slightly more likely to report two or more conditions (9.7% vs 9.3%). Vaccination status by the end of the study differed significantly between both groups. Uninfected participants were more likely to have never been vaccinated (45.3% vs 35.3%) and infected women were more likely to be fully vaccinated before pregnancy (23.7% vs 14.5%) (Table\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e).\u003c/p\u003e\n \u003cp\u003eCharacteristics for all infection group categories can be found in \u003cstrong\u003eAdditional File 7 - Table\u0026nbsp;5\u003c/strong\u003e.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec17\" class=\"Section2\"\u003e\n \u003ch2\u003eMaternal and pregnancy outcomes\u003c/h2\u003e\n \u003cp\u003eOf the participants included in the analytic sample, 604 (5.4%) participants were lost to follow up before end of pregnancy, leaving 2,246 participants with confirmed or probable infection and 1,390 participants with confirmed or probably no infection. Participants classified as possibly infected (n\u0026thinsp;=\u0026thinsp;6,852) were considered in the sensitivity analysis.\u003c/p\u003e\n \u003cp\u003eAccounting for variation by country and after adjusting for maternal age and presence of at least one comorbidity, the risks of emergency Cesarean delivery (RR 1.26, CI 1.03\u0026ndash;1.53) and the composite outcome of maternal morbidity and mortality according to the modified MMMI (RR 1.27, CI 1.12\u0026ndash;1.44) were significantly higher among women infected with SARS-CoV-2 compared to the infected group during the pre-Omicron period (Table\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003e and \u003cstrong\u003eAdditional File 8 - Fig.\u0026nbsp;3\u003c/strong\u003e). During the Omicron era, RR estimates for both of these outcomes were no longer significantly elevated, and the risk for emergency Cesarean delivery was significantly lower among women infected with SARS-CoV-2. None of the other maternal outcomes evaluated had significantly elevated RRs in either variant period \u003cstrong\u003e(\u003c/strong\u003eTable\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003e\u003cstrong\u003e)\u003c/strong\u003e.\u003c/p\u003e\n \u003cp\u003eEight maternal deaths were recorded out of 2,240 (0.4%) SARS-CoV-2-infected women (3 due to confirmed COVID-19, 1 due to postpartum abdominal infection, and 4 unspecified), and 1 out of 1,388 (0.1%) non-infected women (due to pre-eclampsia). Of these nine deaths, 7 occurred during the pre-Omicron era and two during the Omicron era.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec18\" class=\"Section2\"\u003e\n \u003ch2\u003ePerinatal and neonatal outcomes\u003c/h2\u003e\n \u003cp\u003eDuring the pre-Omicron period, the adjusted risks of preterm birth\u0026thinsp;\u0026lt;\u0026thinsp;37 weeks (RR 1.73, CI 1.32\u0026ndash;2.28), as well as \u0026lt;\u0026thinsp;34 weeks (RR 3.69, CI 1.92\u0026ndash;7.09) and \u0026lt;\u0026thinsp;32 weeks (RR 7.58, CI 2.19\u0026ndash;26.19) were significantly higher in the infected group compared to the uninfected group. During the Omicron period the only RR that remained significantly elevated was for preterm birth\u0026thinsp;\u0026lt;\u0026thinsp;34 weeks (RR 1.88, CI 1.04\u0026ndash;3.39). The RR point estimate for preterm birth\u0026thinsp;\u0026lt;\u0026thinsp;32 weeks was similar to that for 34 weeks; however, this association was not statistically significant (RR 1.88, CI 0.55\u0026ndash;6.44) (Table\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003e and \u003cstrong\u003eAdditional File 8 - Fig.\u0026nbsp;3\u003c/strong\u003e). In the first subgroup analyses for preterm birth, which was restricted to those with enrolment dates prior to the respective gestation week, RRs were slightly attenuated but remained significant for preterm birth at all three gestation ages in the pre-Omicron era (\u003cstrong\u003eAdditional File 9 - Table\u0026nbsp;6\u003c/strong\u003e). The significantly increased RR for preterm birth\u0026thinsp;\u0026lt;\u0026thinsp;34 weeks observed in the Omicron era for the main analysis was no longer observed. In the second subgroup analysis based on dates of negative testings, no significant RRs were observed.\u003c/p\u003e\n \u003cp\u003eThe risk of NICU admission was significantly higher in the infected group during the pre-Omicron period (RR 1.90, CI 1.28\u0026ndash;2.82), as was the risk of SPMMI (RR 1.76, CI 1.01\u0026ndash;3.05), but not during the Omicron period. No significant differences were found between groups for other perinatal and neonatal outcomes evaluated.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec19\" class=\"Section2\"\u003e\n \u003ch2\u003ePostpartum outcomes\u003c/h2\u003e\n \u003cp\u003eThe risk of postpartum complications was significantly higher among infected women overall (RR 1.35 CI 1.04\u0026ndash;1.74). During the pre-Omicron period, women with SARS-CoV-2 infection had a significantly lower risk of hemorrhage within the 42 days after delivery compared to the uninfected group (RR 0.39, CI 0.18\u0026ndash;0.84) (Table\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003e and \u003cstrong\u003eAdditional File 8 - Fig.\u0026nbsp;3\u003c/strong\u003e).\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec20\" class=\"Section2\"\u003e\n \u003ch2\u003eSensitivity Analysis\u003c/h2\u003e\n \u003cp\u003eResults for the first sensitivity analysis, which combined \u0026ldquo;possibly\u0026rdquo; infected women with the \u0026ldquo;infected\u0026rdquo; group, are shown in \u003cstrong\u003eAdditional Files 10\u0026ndash;12: Tables\u0026nbsp;7\u0026ndash;9\u003c/strong\u003e. In this analysis, RR point estimates for most outcomes were similar to those in the main analysis or attenuated, with some outcomes no longer significant (e.g., emergency C-section and MMMI) and others becoming significant despite similar RRs (e.g., pre-eclampsia/eclampsia and hypertensive disorders or pregnancy). The only exception to this was for stillbirth and perinatal death, for which RR estimates were higher relative to the main analysis in the pre-Omicron period (e.g., for perinatal death from 28 weeks, the RR was 2.05 (CI 1.44\u0026ndash;2.92)). Due to small numbers, these outcomes could not be evaluated during the Omicron period.\u003c/p\u003e\n \u003cp\u003eIn the first sensitivity analysis, the only outcomes with significantly elevated RRs for the infected group in the Omicron period were preterm birth\u0026thinsp;\u0026lt;\u0026thinsp;34 weeks (RR 2.20, CI 1.46\u0026ndash;3.32) and preterm birth\u0026thinsp;\u0026lt;\u0026thinsp;32 weeks (RR 1.40, CI 1.07\u0026ndash;1.85). Risks for congenital anomalies were notably lower (RR 0.40, CI 0.18\u0026ndash;0.86 after 28 weeks).\u003c/p\u003e\n \u003cp\u003eResults of the second sensitivity analysis, including women \u0026ldquo;possibly\u0026rdquo; infected during pregnancy in the uninfected group, are shown in \u003cstrong\u003eAdditional Files 13\u0026ndash;15 \u0026ndash; Tables\u0026nbsp;10\u0026ndash;12\u003c/strong\u003e. Overall, notable differences with the main analysis include an increased risk for maternal hemorrhage for those in the infected group in the pre-Omicron era (RR 2.42, CI 1.87,3.14) and decreased risks of miscarriage (RR 0.73, CI 0.56\u0026ndash;0.97; Omicron) and of stillbirth (RR 0.55, CI 0.36\u0026ndash;0.82 for 28 weeks; pre-Omicron). In this second sensitivity analysis, the only outcomes with significantly elevated RRs for the infected group in the Omicron period were congenital anomalies (RR 1.94, CI 1.02\u0026ndash;3.70 after 28 weeks).\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec21\" class=\"Section2\"\u003e\n \u003ch2\u003eSeverity of SARS-CoV-2 infections and related outcomes\u003c/h2\u003e\n \u003cp\u003eData on SARS-CoV-2 infection-related symptoms were available for 2,262 (98.1%) women with infection. Of these, 1939 (85.7%) were asymptomatic or had mild symptoms and 323 (14.3%) had moderate to severe symptoms. The most frequently reported symptoms during the pre-Omicron era were fever (36.7%), cough (28.9%), and myalgia (27.9%) whereas rhinitis (27.7%), fever (27.0%) and headache (26.8%) were more frequent during the Omicron period (\u003cstrong\u003eAdditional File 16 - Fig.\u0026nbsp;4\u003c/strong\u003e).\u003c/p\u003e\n \u003cp\u003eAdditionally, the prevalence of moderate to severe infection was significantly lower during the Omicron period compared to the pre-Omicron period (8.9% vs 91.1%), with an adjusted OR of 0.52 (CI 0.34\u0026ndash;0.78), after adjusting for maternal age, comorbidities, and vaccination status (Table\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003e). Vaccination status revealed a protective trend against moderate or severe symptoms. Compared to individuals who were never vaccinated, those who were partially vaccinated had 38% lower odds (OR 0.62; CI 0.38\u0026ndash;1.01) and those fully vaccinated during pregnancy had 53% lower odds (OR\u0026thinsp;=\u0026thinsp;0.47, 95% CI: 0.47\u0026ndash;1.02). These findings were borderline significant, indicating a possible protective effect of vaccination, particularly when administered during pregnancy. Fully vaccinated individuals whose last dose was before pregnancy showed no significant reduction in risk (OR\u0026thinsp;=\u0026thinsp;0.84, 95% CI: 0.57\u0026ndash;1.24).\u003c/p\u003e\n \u003cp\u003ePregnant women who experienced moderate to severe illness were at significantly increased risk of a near-miss indicator at delivery (RR 3.45, CI 2.20\u0026ndash;5.49), MMMI (RR 1.29, CI 1.02\u0026ndash;1.61) and C-section (RR 1.36, CI 1.08\u0026ndash;1.71) (\u003cstrong\u003eAdditional File 17 - Table\u0026nbsp;13\u003c/strong\u003e).\u003c/p\u003e\n \u003cp\u003eTable\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003e. \u003cstrong\u003eRegression model to determine factors associated with severity of illness among SARS-CoV-2 infected women\u003c/strong\u003e\u003c/p\u003e\n\u003c/div\u003e"},{"header":"Discussion","content":"\u003cp\u003eIn this large multi-country prospective cohort study, conducted primarily in LMICs, we evaluated whether SARS-CoV-2 infection during pregnancy increases the risk of adverse maternal, perinatal, neonatal, or postpartum outcomes compared with women without infection during pregnancy, in both pre-Omicron and Omicron periods of SARS-CoV-2 variant predominance. We found that the risks of several adverse outcomes, such as emergency Cesarean delivery, MMMI, preterm birth, NICU admission, SPMMI and postpartum hemorrhage were significantly increased following SARS-CoV-2 infection in pregnancy during the pre-Omicron era. However, these risks were no longer significantly elevated during the Omicron period, for all outcomes except preterm birth before 34 weeks of gestation.\u003c/p\u003e\u003cp\u003eA strength of our study was its prospective design, which used rigorous definitions for both exposure and outcomes. We determined SARS-CoV-2 infection status during pregnancy through universal virologic testing and serial serologic assessments. In contrast, previous individual studies and meta-analyses on this topic have been limited by differing and inexact definitions of exposure status, e.g., relying on a single virologic test to classify participants as \u0026ldquo;negative\u0026rdquo;, increasing the risk of misclassification bias. Others preferentially identified cases with symptomatic infection or at delivery, potentially skewing results toward those more likely to experience adverse outcomes [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. Another strength of our study was the inclusion of a large sample of participants from LMICs in distinct parts of the world. Most prior studies on COVID-19 and pregnancy have been conducted in HICs, where greater access to higher-level care could improve illness-related outcomes while potentially increasing certain clinician-initiated interventions, such as emergency Cesarean section [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. Conversely, in many LMICs, higher baseline rates of outcomes like preterm birth can make it more challenging to detect small absolute increases associated with SARS-CoV-2 infection [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. Differences in underlying comorbidities could also modify risk. Finally, our study is among the few that have evaluated RRs of adverse pregnancy outcomes by comparing pregnant women with and without SARS-CoV-2 infection during the Omicron period. This provides a more accurate reflection of current risks than data collected earlier in the pandemic [\u003cspan additionalcitationids=\"CR4\" citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eA main limitation of our study was that it was originally designed and powered to incorporate serologic testing at a time when few women had previous infection, so the presence of antibody would reflect recent infection [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. However, by the time the study started in many settings, most women were already seropositive. Additionally, data had also emerged that SARS-CoV-2 antibodies could persist over 12 months, meaning that seropositivity could reflect infection prior to pregnancy [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]. Excluding participants whose infection status was not confirmed or probable from the primary analysis improved the accuracy of comparisons, but it also reduced our effective sample size and made our study sample less representative of the general antenatal population, especially as the pandemic progressed. Given the loss of statistical power [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e], some caution needs to be taken in interpreting the lack of significant RRs for adverse outcomes in the Omicron era. Pregnant women with SARS-CoV-2 infection continued to have a significantly increased RR of preterm birth\u0026thinsp;\u0026lt;\u0026thinsp;34 weeks during the Omicron period. For the less common outcome of preterm birth\u0026thinsp;\u0026lt;\u0026thinsp;32 weeks, point estimates remained higher but were no longer statistically significant. It is reassuring that Omicron-era RR point estimates for most outcomes, including preterm birth\u0026thinsp;\u0026lt;\u0026thinsp;37 weeks, were not increased.\u003c/p\u003e\u003cp\u003eOur pre-Omicron era findings align with numerous previous studies demonstrating severe disease and elevated risks of adverse pregnancy-related outcomes associated with SARS-CoV-2 infection during pregnancy earlier in the pandemic [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. Our Omicron era findings differed from another multi-country study by Villar et al, which observed increased composite risks of severe maternal, perinatal, and neonatal morbidity, especially for women with symptomatic COVID-19 [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. A key methodological distinction lies in the timing and classification of Omicron exposure. The prior study included women who delivered within the first six months of the Omicron era using a global date cutoff. In contrast, our analysis defined Omicron exposure based on country-specific data, including only pregnancies that started when more than 75% of circulating variants were Omicron [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. This approach may have reduced misclassification with pre-Omicron infections and better captured the full gestational impact of Omicron-dominant infections. Neither ours nor the Villar study conducted genotyping for individual infections. Additionally, Villar\u0026rsquo;s cohort included more HIC data, whereas ours primarily included data from LMICs. A recent study in Botswana found no differences in adverse maternal and neonatal outcomes among women with and without SARS-CoV-2 infection in pregnancy in the period of Omicron predominance [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eAnother potential explanation for differences between our findings and those of Villar et al. may relate to our use of serologic testing to help define those without infection during pregnancy. As part of our sensitivity analyses, we included those with \u0026ldquo;possible\u0026rdquo; infection during pregnancy (whose only evidence of infection was a positive serologic test) as part of the uninfected group, which more closely aligns with previous studies that have not incorporated serologic testing. However, this did not result in significantly increased RR estimates in the Omicron era for most outcomes, except for congenital anomalies, an association that should be further explored. The varied findings in our sensitivity analyses likely reflect the effects of both increased power due to larger numbers and increased misclassification (as the seropositive are a mix of those infected during pregnancy and those infected earlier). Differences in specific RR estimates in prior studies, such as findings of an increased risk of stillbirth or maternal death in some studies but not others, may depend on the degree of exposure status misclassification [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eThe decline in risk of adverse outcomes during the Omicron period could be attributed to a decrease in virulence of Omicron variants, or to increased prior immunity, from previous infection, vaccination, or both [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]. Several studies have demonstrated a decrease in overall severity of illness in pregnancy during the Omicron period compared with earlier periods, as observed in nonpregnant adults [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e, \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]. We found that among those with SARS-CoV-2 infection, women had lower odds of moderate or severe illness during the Omicron era compared to the pre-Omicron era, regardless of previous vaccination. In turn, controlling for variant period, the odds of moderate to severe illness were around 53% lower if women were fully vaccinated with the latest dose in pregnancy compared with no vaccination. Although in a borderline statistical significance, this finding is important because, among all those with infection in pregnancy, women with more severe illness had higher risks of adverse outcomes such as maternal near-miss at delivery, MMMI, and C-section (this analysis was not sufficiently powered to evaluate separately by variant period) [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eOur findings have implications for risk-benefit assessments for interventions in pregnancy, including vaccination. As of September 2025, WHO recommendations are for pregnant women to receive one dose of COVID-19 vaccine in each pregnancy [\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e], based on the increased risk of adverse outcomes in pregnancy observed in previous literature [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e], along with numerous studies showing that vaccines are safe and effective in preventing severe COVID-19 illness for pregnant women and infants, even in the Omicron era [\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e]. The findings of this study contribute to those considerations and provide reassurance that the risk of adverse outcomes has decreased as the pandemic has progressed. However, the ongoing signals for an increased risk of early preterm births for women infected during Omicron-era, and potentially for additional outcomes in sensitivity analyses with greater sample size, mean that there may be ongoing risks. We did not have data from more recent Omicron sub-variant periods. Continued monitoring can evaluate evolving risk profiles of new variants [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e], although the large proportion of women with prior hybrid immunity is reassuring that we will not go back to the morbidity seen earlier in the pandemic [\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e]. However, an important consideration is that the lower risks observed in the Omicron period might be related to increased overall vaccination levels\u0026mdash;and ongoing vaccination in pregnancy\u0026mdash;which we were not fully able to evaluate. A disproportionate number of vaccinated individuals were excluded from the current analysis, preferentially from the uninfected group, based on our use of negative serologic testing at the end of pregnancy to confirm lack of infection. Serologic testing cannot distinguish natural from vaccine-induced antibodies following receipt of inactivated vaccines, which were used by almost a third of those vaccinated and almost 15% of the entire study sample. The separate COVID-19 vaccine evaluation from this study, conducted among the entire study population of 16,007 participants without limiting to those with known infection status, will provide additional information to the risk-benefit equation.\u003c/p\u003e"},{"header":"Conclusions","content":"\u003cp\u003eIn summary, this prospective cohort study among pregnant women in 10 countries, one of the largest evaluating COVID-19 and pregnancy in primarily LMICs, found that SARS-CoV-2 infection during pregnancy increased the risk of several maternal, perinatal, and neonatal outcomes mainly during the pre-Omicron era. These data provide reassurance that during the Omicron era, when a large proportion of pregnant women also have immunity from prior infection or vaccination, relative risks are largely attenuated. However, some evidence of increased risk remains, for example in preterm births\u0026thinsp;\u0026lt;\u0026thinsp;34 weeks of gestation. Continued evaluation of data on SARS-CoV-2 illness and pregnancy outcomes, especially in the context of emerging variants and newer Omicron sub-variants, and further exploration of the effects of COVID-19 vaccination during the Omicron and Omicron sub-variant periods would be valuable. As most prior data on COVID-19 and pregnancy outcomes have been from HICs, this study also highlights the importance of generating quality outbreak-related data in LMICs, to ensure the health of pregnant women and their neonates globally.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis study was conducted in accordance with the ethical principles outlined in the Declaration of Helsinki for research involving human participants and relevant national and institutional guidelines. The generic protocol received approval from the WHO Ethics Review Committee (WHO ERC). Country-specific protocols were also submitted for review and approved by both the WHO ERC and the Institutional Review Boards (IRBs) of each participating country. Written informed consent or assent was obtained from all participants prior to their inclusion. Ethics approval committees and timelines are as follows:\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eGeneric protocol - World Health Organization (WHO):\u0026nbsp;\u003c/strong\u003eWHO Ethics Review Committee (ERC) approval granted on 18 August 2020 (Ref: CERC.0008), with continuing review approval on 1 September 2021 and amendment approval on 5 July 2022 (Ref: CERC.0008).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCountry-adapted protocols:\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eArgentina:\u0026nbsp;\u003c/strong\u003eEthical approval obtained from the Pan American Health Organization Ethics Review Committee (PAHOERC) on 4 November 2021 (Ref: PAHOERC.0428.03), and from the following local ethics committees: Comité de Ética Independiente del CREP on 22 September 2021; Ref 3_21, Comité de Ética del Hospital Materno Neonatal “Eloisa Torrent de Vidal” on 14 June 2021, and Comité de Ética del Hospital Privado – Centro Médico de Córdoba on 10 September 2021; Ref HP4-346.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eBrazil:\u0026nbsp;\u003c/strong\u003eEthical approval obtained from PAHOERC on 2 July 2021 (Ref: PAHOERC.0369.02) and on 23 March 2023, and from the following local ethics committee for all centers: Comissão Nacional de Ética em Pesquisa (CONEP) on 30 June 2021 (Ref: 4.817.831), with amendments approved on 6 June 2023. \u003cstrong\u003eBurkina Faso:\u0026nbsp;\u003c/strong\u003eEthical approval requirements were waived by the WHO African Region Ethics Review Committee (AFRO ERC) on 3 August 2021 (Ref: AFR/ERC/2021/8.2) and on 23 June 2023 (Ref: AFR/ERC/2023/6.10). Local approval was obtained from the Comité d’éthique pour la recherche en Santé (CERS) on 2 June 2021, with amendments approved on 7 June 2023.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eChile:\u0026nbsp;\u003c/strong\u003eEthical approval was obtained from the World Health Organization (WHO) / Pan American Health Organization (PAHO) Ethics Review Committee (Ref. PAHOERC.0590.02; approval dated 16 December 2022), as well as from the following local ethics committees in Chile:\u0026nbsp;Comité de Ética Científica de la Dirección de Servicio de Salud Araucanía Sur (approval dated 21 October 2021; Ref. 244), Comité de Ética Científica de la Dirección de Servicio de Salud Araucanía Sur (approval dated 23 March 2023; Ref. 57), Comité Ético Científico del Servicio de Salud del Reloncaví – Hospital Puerto Montt (approval dated 26 July 2021; Ref. 16), and Dirección de Servicio de Salud Araucanía Sur – Hospital Dr. Hernán Henríquez Aravena (approval dated 30 March 2023; Ref. 2553).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eGhana:\u0026nbsp;\u003c/strong\u003eWHO AFRO ERC approval obtained on 26 February 2021 (Ref: AFR/ERC/2021/2.2), with local approvals granted by the Ghana Health Service Ethics Review Committee on 26 April 2021 and 11 November 2021 (Ref: GHSERC 017/02/21), and by the University of Ghana IRB on 28 October 2021 (IRB00006220).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eKenya:\u0026nbsp;\u003c/strong\u003eWHO AFRO ERC approval on 25 February 2021 (Ref: AFR/ERC/2021/2.4) with continuing approval on 14 April 2023 (Ref: AFR/ERC/2023/4.1). Local approvals from Aga Khan University, Nairobi on 12 May 2021 (Ref: 2020/IERC-153 (v2)) and 6 March 2023 (Ref: 2020/IERC-153 (V3)), and from the National Commission for Science, Technology and Innovation (NACOSTI) on 9 June 2021 (Ref: 336896).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003ePakistan:\u0026nbsp;\u003c/strong\u003eWHO Eastern Mediterranean Regional Ethics Review Committee (EMRERC) approval with waiver in 2021 and 10 December 2023. Local approvals obtained from the Aga Khan University Ethics Review Committee on 26 February 2023 (Ref: 2023-5838-24122), with amendments approved on 17 February 2022 (Ref: 2022-5838-20665), 18 May 2022 (Ref: 2022-5838-21504), and 8 November 2022 (Ref: 2022-5838-23158). National Bioethics Committee approvals were granted on 23 February 2021 (Ref: 4-87/COVID-62/NBC/21), with amendment and extension approvals on 26 May 2021 and 5 September 2022 (Ref: 4-87/COVID-62/22/294).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003ePhilippines:\u0026nbsp;\u003c/strong\u003eWHO Western Pacific Regional Ethics Review Committee (WPRO-ERC) approval on 27 August 2021 (Ref: 2021.14.PHL.3.MCN). Local approvals from the Single Joint Research Ethics Board (SJREB) on 19 May 2021 (Ref: SJREB-2020-30) and 20 February 2023 (amendment), the University of the Philippines Manila Research Ethics Board (UPMREB) on 9 June 2021 (Ref: 2020-320-01-SJREB) and 10 March 2023 (continuing review; Ref: IRB 2020-18-4), and the Research Institute for Tropical Medicine – Department of Health on 11 June 2021 (Ref: IRB 2020-18-2).\u003cbr\u003e\u003cstrong\u003eSpain:\u0026nbsp;\u003c/strong\u003eComité Ético de Investigación de la Dirección General de Salud Pública y Centro Superior de Investigación en Salud Pública approval obtained on 21 December 2020 (Ref: 20201221/06), and Comité Ético de Investigación Clínica del Hospital Universitario Doctor Peset de Valencia approval obtained on 29 November 2021.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTunisia:\u0026nbsp;\u003c/strong\u003eEMRERC approvals (with waiver) on 19 October 2021 and 3 March 2023, on the basis of local approvals obtained from: the Comité d’éthique du Centre de Maternité et de Néonatologie de Tunis on 23 July 2021, and from the Comité d’éthique Biomédicale de l’Institut Pasteur de Tunis on 29 July 2021 (Ref: 2021/12/I/LR16IPT/V1), with amendment approval on 26 June 2023 (Ref: 2022/12/I/LR16IPT/Amendment/V1).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eInformed Consent:\u0026nbsp;\u003c/strong\u003eObtained from all study participants prior to enrolment in the study, and in accordance with WHO ERCs and local ethics committee requirements.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable. This manuscript does not contain any individual’s data in any form (including individual details, images, or videos) that require consent for publication.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailability of data and materials\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eResearch study data that support the findings of this study may be requested by completing a concept note available from the corresponding author. \u0026nbsp;An anonymized dataset will be made available upon approval of the multi-country editorial board with data share agreement from the country principal investigators.\u003c/p\u003e\n\u003cul\u003e\n \u003cli\u003e\u003cstrong\u003eCompeting interests\u003c/strong\u003e\u003c/li\u003e\n\u003c/ul\u003e\n\u003cp\u003eThe authors declare no competing interests.\u003c/p\u003e\n\u003cul\u003e\n \u003cli\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/li\u003e\n\u003c/ul\u003e\n\u003cp\u003eThe project was partially supported by the Bill and Melinda Gates Foundation, Ref: Investment ID INV-041181, the United States Department of State, the German Federal Ministry of Health (BMG) COVID-19 Research and development support to the World Health Organization (WHO), Ref: MG 2022 support to WHO SPRP ACT-A, and UNDP-UNFPA-UNICEF-WHO-World Bank Special Programme of Research, Development and Research Training in Human Reproduction (HRP), a co-sponsored programme executed by WHO. The funders had no specific role in the conceptualization, design, data collection, analysis, decision to publish, or preparation of the manuscript. The authors alone are responsible for the views expressed in this article and they do not necessarily represent the views, decisions, or policies of the institutions with which they are affiliated. RHR TRIMS Project ID no. A66012”\u0026nbsp;\u003c/p\u003e\n\u003cul\u003e\n \u003cli\u003e\u003cstrong\u003eAuthors' contributions\u003c/strong\u003e\u003c/li\u003e\n \u003cli\u003e\u003cstrong\u003eWHO COVID-19 Pregnancy Cohort Study Group\u003c/strong\u003e\u003c/li\u003e\n\u003c/ul\u003e\n\u003cp\u003eThe following are the manuscript authors comprising the WHO COVID-19 Pregnancy Cohort Study Group. In each Implementing Country Team, the leads/principal investigators are followed by remaining group members in alphabetical order:\u0026nbsp;\u003c/p\u003e\n\u003cul\u003e\n \u003cli\u003e\u003cstrong\u003eWHO\u0026nbsp;\u003c/strong\u003e\u003cstrong\u003eCoordinating Team:\u003c/strong\u003e\u003csup\u003e1\u003c/sup\u003e Edna Kara\u003csup\u003e§\u003c/sup\u003e, Sami L Gottlieb\u003csup\u003e§\u003c/sup\u003e, Nathalie J Broutet\u003cu\u003e,\u003c/u\u003e Anna Thorson, Marie Delnord, Ibukun-Oluwa Omolade Abejirinde.\u0026nbsp;\u003c/li\u003e\n \u003cli\u003e\u003cstrong\u003eWHO Data Management and Analysis Team:\u003c/strong\u003e\u003csup\u003e1\u003c/sup\u003e Ronaldo Silva\u003csup\u003e£\u003c/sup\u003e, Soe Soe Thwin\u003csup\u003e£\u003c/sup\u003e, Daniel Giordano, Ndema Abu Habib.\u0026nbsp;\u003c/li\u003e\n \u003cli\u003e\u003cstrong\u003eImplementing Country Teams\u0026nbsp;\u003c/strong\u003e(countries in alphabetical order)\u003cstrong\u003e:\u003c/strong\u003e\u0026nbsp;\u003c/li\u003e\n \u003cli\u003e\u003cstrong\u003eArgentina\u003c/strong\u003e\u003csup\u003e2\u003c/sup\u003e: Edgardo Abalos*.\u0026nbsp;\u003c/li\u003e\n \u003cli\u003e\u003cstrong\u003eBrazil\u003c/strong\u003e\u003csup\u003e3\u003c/sup\u003e: José G Cecatti*; Maria L Costa; Renato T Souza.\u0026nbsp;\u003c/li\u003e\n \u003cli\u003e\u003cstrong\u003eBurkina\u003c/strong\u003e\u003cstrong\u003eFaso\u003c/strong\u003e\u003csup\u003e4\u003c/sup\u003e: Seni Kouanda*; Desiré L. Dahourou; Henri Gautier Ouedraogo.\u0026nbsp;\u003c/li\u003e\n \u003cli\u003e\u003cstrong\u003eChile\u003c/strong\u003e\u003csup\u003e5\u003c/sup\u003e: Sergio Munoz*; Gerardo Espinoza; Araceli Saavedra.\u0026nbsp;\u003c/li\u003e\n \u003cli\u003e\u003cstrong\u003eGhana\u003c/strong\u003e\u003csup\u003e6\u003c/sup\u003e: Kwasi Torpey*; Chris Guure; Ernest Maya; Emefa Modey.\u0026nbsp;\u003c/li\u003e\n \u003cli\u003e\u003cstrong\u003eKenya\u003c/strong\u003e: Marleen Temmerman\u003csup\u003e7\u003c/sup\u003e*; Rodney D. Adam\u003csup\u003e7\u003c/sup\u003e; Ingrid Gichere\u003csup\u003e7\u003c/sup\u003e; Sura Mandeep\u003csup\u003e8\u003c/sup\u003e.\u0026nbsp;\u003c/li\u003e\n \u003cli\u003e\u003cstrong\u003ePakistan\u003c/strong\u003e\u003csup\u003e9\u003c/sup\u003e: Sarah Saleem*; Najia Ghanchi; Saleem Jessani.\u0026nbsp;\u003c/li\u003e\n \u003cli\u003e\u003cstrong\u003ePhilippines\u003c/strong\u003e: Erlidia Llamas-Clark\u003csup\u003e10,11\u003c/sup\u003e*; Emmanuel S Baja\u003csup\u003e10\u003c/sup\u003e; Mayan U Lumandas\u003csup\u003e12\u003c/sup\u003e.\u0026nbsp;\u003c/li\u003e\n \u003cli\u003e\u003cstrong\u003eSpain\u003c/strong\u003e\u003csup\u003e13\u003c/sup\u003e: Alejandro Orrico-Sánchez*; Antonio Carmona.\u0026nbsp;\u003c/li\u003e\n \u003cli\u003e\u003cstrong\u003eTunisia\u003c/strong\u003e: \u0026nbsp;Henda Triki\u003csup\u003e14,15\u003c/sup\u003e*; Mariem Gdoura\u003csup\u003e14-16\u003c/sup\u003e.\u0026nbsp;\u003c/li\u003e\n \u003cli\u003eAlso see in the acknowledgements the full list of contributors in each country. \u0026nbsp;\u003c/li\u003e\n \u003cli\u003e\u003csup\u003e§\u003c/sup\u003eCo-lead authors \u003csup\u003e£\u003c/sup\u003eCo-lead analyst/statisticians, *Principal Investigators.\u003c/li\u003e\n\u003c/ul\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cu\u003eAffiliations\u003c/u\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003col\u003e\n \u003cli\u003eDepartment of Sexual and Reproductive Health and Research including the Human Reproduction Programme (HRP), World Health Organization, Geneva, Switzerland\u0026nbsp;\u003c/li\u003e\n \u003cli\u003eCentro Rosarino de Estudios Perinatales (CREP), Rosario, Argentina\u003c/li\u003e\n \u003cli\u003eDepartment of Obstetrics and Gynecology, University of Campinas, Brazil\u003c/li\u003e\n \u003cli\u003eInstitut de Recherche en Sciences de la Santé (IRSS), Uagadugu, Burkina Faso\u003c/li\u003e\n \u003cli\u003eUniversity de La Frontera, Temuco, Chile\u003c/li\u003e\n \u003cli\u003eSchool of Public Health, University of Ghana, Accra, Ghana\u003c/li\u003e\n \u003cli\u003eAga Khan University, Nairobi, Kenya\u0026nbsp;\u003c/li\u003e\n \u003cli\u003ePumwani Maternity Hospital\u003c/li\u003e\n \u003cli\u003eDepartment of Community Health Sciences, Aga Khan University, Karachi, Pakistan.\u003c/li\u003e\n \u003cli\u003eUniversity of the Philippines, Manila, Philippines\u003c/li\u003e\n \u003cli\u003eInstitute of Child Health and Human Development, National Institutes of Health, University of the Philippines, Manila, Philippines.\u003c/li\u003e\n \u003cli\u003eResearch Institute for Tropical Medicine-Department of Health, Manila, Philippines\u003c/li\u003e\n \u003cli\u003eDepartment of Vaccines Research, Fundación Para el Fomento de la Investigación Sanitaria y Biomédica de la Comunitat Valenciana (Fisabio), Valencia, Spain\u003c/li\u003e\n \u003cli\u003eResearch Laboratory \"Virus, Vectors and Hosts”, LR20IPT02, Pasteur Institute, University Tunis El-Manar (UTM), Tunis, Tunisia\u003c/li\u003e\n \u003cli\u003eClinical Investigation Center (CIC2016IPT02), Institut Pasteur de Tunis, University of Tunis El Manar.\u003c/li\u003e\n \u003cli\u003eFaculty of Pharmacy, University of Monastir, Monastir, Tunisia\u003c/li\u003e\n\u003c/ol\u003e\n\u003cp\u003eThe original generic protocol of the study was conceptualized and had the first draft written by the staff of WHO. The adaptation of the generic protocol to each participant country´s characteristics was performed by each country´s PI and Co-PIs with the support of the WHO team. \u0026nbsp;The current manuscript was first drafted by EK and SLG with initial inputs from by-lined authors. Data collection was performed by the local study teams. Data was managed, cleaned and processed by DG. The statistical analysis was conducted by RS and SST, who also provided input to the initial manuscript. Initial interpretation of findings was conducted by EK, SLG, RS and SST. A second round of input was performed by the WHO team including all COVID-19 PCS investigators and co-investigators. A third round of input was received from all authors, who also read and approved the final manuscript to be submitted for publication. \u0026nbsp;The authors alone are responsible for the views expressed in this article, and they do not necessarily represent the views, decisions, or policies of the institutions with which they are affiliated. Additional contributors in each country are listed in the acknowledgements.\u003cbr\u003e\u003cstrong\u003eAcknowledgements\u003c/strong\u003e\u003cbr\u003eWe extend our heartfelt gratitude to the women who participated in this study. We also wish to express our appreciation to the institutions and individuals who contributed to this project’s design and implementation. This includes researchers, study coordinators, data collectors, data clerks, and other partners, as well as the staff from the Ministries of Health and WHO Regional and Country Offices. Hospital site investigators are listed below, followed by any additional collaborators by country and in alphabetical order.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eArgentina:\u0026nbsp;\u003c/strong\u003eJesús D Aguirre; Lucia Bóccoli; Pablo Gola; Elba MA Morales; Constanza Poenitz; Savino Gil Pugliese; Sofía Roggi; Gabriela C Taborda. Additional collaborators: Raúl H Capra; Micaela Y Colussi; Hernán G De La Rocha Morales; Florencia Ducart Díaz; Karina MA Fernández; Soledad C Fleita; Silvia Galetto; Florencia L García; Martín L García; Luis G Mercado; Jesica N Esquivel Quiñones; Sofía G Salguero; Luciana Simes; Nicole Toutain.\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e \u003cstrong\u003eBrazil:\u0026nbsp;\u003c/strong\u003eMário D Corrêa-Júnior; Edson V Cunha Filho; Samira M Haddad; Débora F Leite; Marília GQ Luz; Ana S Picoloto; Carla Silveira; Ricardo P Tedesco; Evelyn Traina. \u0026nbsp; Additional collaborators: Sabrina Aguiar; Pedro Albuquerque; Julia S Almeida; Gabriela S Alves; Junia Andrade; Luísa S Andrade; Artur A Antolini; \u0026nbsp;Annerose Barros; Guilherme Bese; Anne Bergmann; Mariana Brasileiro; Gislânia PF Brito; Laura F Brum; Telma RM Campello; Danilo G Cardim; Anna TS Cardoso; Bianca S Carrara; Aline Cavalcante; Marcela MT Cavalcante; Euriane C Costa; Juliana Costa Santos; Mariany C Cottet-Moratori; Sarah Dariva; Helena M Dreschler; Karayna G Fernandes; \u0026nbsp;Karina MA Fernández; Leydiane A Ferreira; Josiane Fonseca De Oliveira; Juliana S Franciscato; Hellen T Fuzii; Silvia Galetto; Rafael B Galvão; Andrezza A Guerra; Luciano Guimaraes; Luciana Iadoccico; Giuliane J Lajos; Amanda B Lima-Silva; Rhayssa Lucena; Adriana G Luz; Ellen Machado; Manoela Maffei; Sérgio HA Martins-Costa; Aline D Maranhão; Silvia B Mazon; Jussara Mayrink; Lorena R Medeiros; Marina Melo; Elias F Melo Junior; Sherly Metelus; Isabella Monteiro; Charles M’poca; \u0026nbsp;Ana L Muller; Bárbara SP Neres; Patricia Nessralla; Guilherme M Nobrega; Adriane Oliveira; Thais O Oliveira; Melina MS Oliveira; Yasmin F Oliveira Silva; \u0026nbsp; Maria LR Oppermann; Rodolfo C Pacagnella ; Ana S Picoloto; Laiza S Quadro; José G Ramos; Gustavo Raupp; Carolina C Ribeiro-Do-Valle; Clélia A Salustrino; Sabrina Savazoni; Eduardo Serra; Arthur Simoes; Carla L Silva; Deborah Silva; Elisabete P Silva; Fabricio Souto; Camila Cd Souza; Natália C Souza; Luiza Q Stein; Aline Tosetto; Juliana Trevizo; \u0026nbsp;Janete Vettorazzi.\u0026nbsp;\u003cstrong\u003eBurkina Faso:\u003c/strong\u003e Ignace Béré; Ousmane Bague; Todara Dabal/Yabre; Anselme KP Somda; Sylvain Ko; Frederic Paul Patarb-Taale Kobinde; Philippe Tassembedo; Toudala Paré; Honorine Tougouma; Hamado Ouedraogo; François Yameogo. Additional collaborators: Blandine Bonane Thieba; Rebeca Compaore; Issa Kaboré; Tani Sagna; Angèle Zan. \u003cstrong\u003eChile:\u003c/strong\u003e\u0026nbsp; Margot Acuña; Evelyn Brunman; Jose Caro; \u0026nbsp;Dorothy Fica; Arantza Solis; Valeria Urbina. \u0026nbsp;\u003cstrong\u003eGhana:\u0026nbsp;\u003c/strong\u003eRichard Anthony; Franklin Asiedu-Bekoe; Kennedy Brightson; Evelyn Bonney; Joycelyn Dame; Roseline Doe; Sarpong Ntiamoah; Samuel Oppong. \u0026nbsp;Additional collaborators: Amos Apreku; Caroline Badzi; Maxwell Boakye Agyemang; Derrick Holdbrook; Alhassan Yakubu. \u003cstrong\u003eKenya:\u003c/strong\u003e Beth Maina, Rosalin Ochieng. Additional collaborators: Tahera Khatau; Josephine Kizidio; Roy Moki; Bancy Ngatia; Barack Obara; Jasmit Shah. \u003cstrong\u003ePakistan\u003c/strong\u003e: Sadia Aftab, Khalil Ahmad, Imran Ahmed, Naheed Akhter, Noreen Akmal, Talha Ali, Shabina Ariff, Sarwat Bukhari, Shireen Gul, Shamsa Humayun, Muhammad Riaz Hussain, Saba Khan, Zohra Khanum, Erum Majid, Shazia Masheer, Salman Muhammad, Shamila Ijaz Munir, Amtul Quddos, Rehana Rahim, Syeda K Riaz, Ahmareen K Sheikh, Lumaan Sheikh, Summaya Sohail, Shahid Tanveer, Shahida Tasneem, Zeeshan Uddin, Massab Umair, Shagufta Yasmeen, Haleema Yasmin, Afia Zafar, Farnaz Zahoor, Leila Zeb. Additional collaborators: Saira Afghan; Khadija Bano; Zaheer Habib; Aisha Malik; Syeda B Mazhar; Sayyeda Reza; Sana Yusuf. \u003cstrong\u003ePhilippines\u003c/strong\u003e: Maria Stephanie Fay S. Cagayan; Francisco M. Heralde; Paulyn Jean B. Rosell-Ubial; Maria Esterlita V. Yu. Additional collaborators: Maria Lu D. Andal; Julia B. Beltran; Charizze Anne S. Cabana; Ryan B. Capitulo; Malaya M. Capulong; Leilani C. Chavez-Coloma; Vanessa D. De Guzman; Arlene R. Dominguez; ; Carolina Paula C. Martin; Amalea D. Nicolasora; Maricris D. Pacoli-Corduwa; Coney S. Pacua-Platero; Celine D. Quanico; Mary Abigail T. Roque; \u0026nbsp;Merle D. Sacdalan-Faustino; Margarette Gale P. Santos; Maria Cecilia O. Tolentino; Cynthia L. Ubaldo-Anzures; Eleyneth I. Valencia; Daniel C. Villarico.\u0026nbsp;\u003cstrong\u003eSpain\u003c/strong\u003e: Cristina Ruiz-Aguilar, Elia García-Verdevio. \u0026nbsp;Additional collaborators: Reyes Balanza; Celia Barber-Almenar; Pilar Codoñer; Beatriz Mansilla-Roig; Alicia Martínez-Sebastián; María Navío Anaya; Vallivana Rodrigo-Casares.\u0026nbsp;\u003cstrong\u003eTunisia:\u0026nbsp;\u003c/strong\u003eNesrine Abderahmane; Youssef Atef; Emna Barkaoui; Med Bedis Channoufi; Majdi Ben Ameur; Rim Ben Hmid; Dalenda Chelli; Myriam Cheour; Hajer Chourou; Samia Kacem; Khaoula Magdoud; Hiba Mkadmi; Khaled Neji. \u0026nbsp;Additional collaborators: Wajih Abidi; \u0026nbsp;Tessnim Aissaoui; Amira Ammar; Jamel Ammar; \u0026nbsp;Radhia Ammi; Monia Ardhaoui; Sonia Attia; Imen Ayari; Emna Barkaoui; Zeineb Belaiba; Sahar Belayeb; Besma Belgasmi; Wafa Belhaj Ammar; Samar Ben Hlima; \u0026nbsp; Nadia Benameur; Achref Ben Messoud; Ameny Ben Rabiaa; Med Samir Boubaker; Wafa Chamsa; Asma Cherni; Riadh Daghfous; Ayhem Dahmeni; Hafedh Dakhlaoui; Sihem El Aidli; Cyrine El Fekih; Emna Fehri; Aymen Ferjaoui; Manel Gharbi; Walid Hammemi; Nahed Hogga; Leila Jabri; Zeineb Jarraya; Abir Jlassi; Maria Kabbage; Sana Kalthoum; Abir Karoui; Besma Khalledi; Chadha Khemissi; Henda Krichen; Hechmi Louzir; Mouna Maghrabi; Lamia Mannai; Zina Meddeb; Fethi Mraihi; Alaya Nabiha; Fatma Naffeti; Anissa Noury; Soumayya Ouhibi; Kaouther Ouerhani; Nadia Rahalai; Abir Rebhi; Khaoula Rezgui; Rihab Romdhane; Amel Sadraoui; Khaoula Samaali; Henda Touzi; Fatma Zgolli.\u003c/p\u003e\n\u003cp\u003eFinally, we have listed below the contributing authors of the \u003cem\u003eWHO COVID-19 Pregnancy Cohort Study group:\u0026nbsp;\u003c/em\u003e\u003cstrong\u003eWHO\u0026nbsp;\u003c/strong\u003e\u003cstrong\u003eCoordinating Team\u0026nbsp;\u003c/strong\u003e(by descending order of contribution)\u003cstrong\u003e:\u003c/strong\u003e\u003csup\u003e1\u003c/sup\u003e Edna Kara\u003csup\u003e§\u003c/sup\u003e, Sami L Gottlieb\u003csup\u003e§\u003c/sup\u003e, Nathalie J Broutet\u003cu\u003e,\u003c/u\u003e Anna Thorson, Marie Delnord, Ibukun-Oluwa Omolade Abejirinde. \u003cstrong\u003eWHO Data Management and Analysis Team\u0026nbsp;\u003c/strong\u003e(by descending order of contribution)\u003cstrong\u003e:\u003c/strong\u003e\u003csup\u003e1\u003c/sup\u003e Ronaldo Silva\u003csup\u003e£\u003c/sup\u003e, Soe Soe Thwin\u003csup\u003e£\u003c/sup\u003e,\u0026nbsp;Daniel Giordano, Ndema Abu Habib. \u003cstrong\u003eImplementing Country Teams\u0026nbsp;\u003c/strong\u003e(by country and in alphabetical order)\u003cstrong\u003e:\u003c/strong\u003e \u003cstrong\u003eArgentina\u003c/strong\u003e\u003csup\u003e2\u003c/sup\u003e: Edgardo Abalos*.\u0026nbsp;\u003cstrong\u003eBrazil\u003c/strong\u003e\u003csup\u003e3\u003c/sup\u003e:\u0026nbsp;José G Cecatti*;\u0026nbsp;Maria L Costa; Renato T Souza. \u003cstrong\u003eBurkina\u003c/strong\u003e \u003cstrong\u003eFaso\u003c/strong\u003e\u003csup\u003e4\u003c/sup\u003e: Seni Kouanda*; Desiré L. Dahourou; Henri Gautier Ouedraogo.\u0026nbsp;\u003cstrong\u003eChile\u003c/strong\u003e\u003csup\u003e5\u003c/sup\u003e: Sergio Munoz*; Gerardo Espinoza; Araceli Saavedra.\u0026nbsp;\u003cstrong\u003eGhana\u003c/strong\u003e\u003csup\u003e6\u003c/sup\u003e: Kwasi Torpey*; Chris Guure; Ernest Maya; Emefa Modey. \u003cstrong\u003eKenya\u003c/strong\u003e: Marleen Temmerman\u003csup\u003e7\u003c/sup\u003e*; Rodney D. Adam\u003csup\u003e7\u003c/sup\u003e; Ingrid Gichere\u003csup\u003e7\u003c/sup\u003e; Sura Mandeep\u003csup\u003e8\u003c/sup\u003e. \u003cstrong\u003ePakistan\u003c/strong\u003e\u003csup\u003e9\u003c/sup\u003e: Sarah Saleem*; Najia Ghanchi; Saleem Jessani. \u003cstrong\u003ePhilippines\u003c/strong\u003e: Erlidia Llamas-Clark\u003csup\u003e10,11\u003c/sup\u003e*; Emmanuel S Baja\u003csup\u003e10\u003c/sup\u003e; Mayan V Lumandas\u003csup\u003e12\u003c/sup\u003e. \u003cstrong\u003eSpain\u003c/strong\u003e\u003csup\u003e13\u003c/sup\u003e: Alejandro Orrico-Sánchez*; Antonio Carmona. \u003cstrong\u003eTunisia\u003c/strong\u003e: \u0026nbsp;Henda Triki\u003csup\u003e14\u003c/sup\u003e*; Mariem Gdoura\u003csup\u003e14,15\u003c/sup\u003e. Also see in the acknowledgements the full list of contributors in each country. \u0026nbsp;*Principal Investigators § Lead authors £ Lead analyst/Statistician\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eAllotey J, Fernandez S, Bonet M, Stallings E, Yap M, Kew T, et al. Clinical manifestations, risk factors, and maternal and perinatal outcomes of coronavirus disease 2019 in pregnancy: living systematic review and meta-analysis. BMJ. 2020;370:m3320. doi:10.1136/bmj.m3320\u003c/li\u003e\n\u003cli\u003eSmith ER, Oakley E, Grandner GW, Perinatal COVID PMA Study Collaborators, et al. Adverse maternal, fetal, and newborn outcomes among pregnant women with SARS-CoV-2 infection: an individual participant data meta-analysis. BMJ Glob Health. 2023;8:e009495.\u003c/li\u003e\n\u003cli\u003eMupanomunda M, Fakih MG, Miller C, et al. Comparison of severe maternal morbidities associated with delivery during periods of circulation of specific SARS-CoV-2 variants. JAMA Netw Open. 2022;5(8):e2226436. doi:10.1001/jamanetworkopen.2022.26436\u003c/li\u003e\n\u003cli\u003eVillar J, Ariff S, Gunier RB, et al. Maternal and neonatal morbidity and mortality among pregnant women with and without COVID-19 infection: the INTERCOVID multinational cohort study. JAMA Pediatr. 2021;175(8):817\u0026ndash;826.\u003c/li\u003e\n\u003cli\u003eBanga J, Jackson-Gibson M, Diseko M, Caniglia EC, Mayondi G, Mabuta J, et al. No impact of COVID-19 at delivery on maternal mortality or infant adverse birth outcomes in Botswana during the Omicron era. PLoS One. 2024;19(9):e0310980. doi:10.1371/journal.pone.0310980\u003c/li\u003e\n\u003cli\u003eWorld Health Organization, UNICEF, UNFPA, World Bank Group, UNDESA/Population Division. Trends in maternal mortality estimates 2000 to 2023. Available from: https://www.who.int/publications/i/item/9789240108462\u003c/li\u003e\n\u003cli\u003eGeneric protocol: a prospective cohort study investigating maternal, pregnancy and neonatal outcomes for women and neonates infected with SARS-CoV-2. 1 Nov 2022.\u003c/li\u003e\n\u003cli\u003eAmerican College of Obstetricians and Gynecologists. Committee Opinion: Methods for Estimating the Due Date. No. 700. May 2017.\u003c/li\u003e\n\u003cli\u003eShu Y, McCauley J. GISAID: global initiative on sharing all influenza data \u0026ndash; from vision to reality. Euro Surveill. 2017;22. doi:10.2807/1560-7917.ES.2017.22.13.30494\u003c/li\u003e\n\u003cli\u003eWorld Health Organization. Caesarean section rates continue to rise, amid growing inequalities in access.\u003c/li\u003e\n\u003cli\u003eVogel JP, Lee AC, Souza JP. Maternal morbidity and preterm birth in 22 low- and middle-income countries: a secondary analysis of the WHO Global Survey dataset. BMC Pregnancy Childbirth. 2014;14:56. doi:10.1186/1471-2393-14-56\u003c/li\u003e\n\u003cli\u003eHolmer HK, Mackey K, Fiordalisi CV, Helfand M. Major Update 2: antibody response and risk for reinfection after SARS-CoV-2 infection\u0026mdash;final update of a living, rapid review. Ann Intern Med. 2023;176(1):85\u0026ndash;91. doi:10.7326/M22-1745\u003c/li\u003e\n\u003cli\u003eSigal A. Milder disease with Omicron: is it the virus or the pre-existing immunity? Nat Rev Immunol. 2022;22:69\u0026ndash;71. doi:10.1038/s41577-022-00678-4\u003c/li\u003e\n\u003cli\u003eStock SJ, Moore E, Calvert C, Carruthers J, Denny C, Donaghy J, et al. Pregnancy outcomes after SARS-CoV-2 infection in periods dominated by Delta and Omicron variants in Scotland: a population-based cohort study. Lancet Respir Med. 2022;10(12):1129\u0026ndash;1136. doi:10.1016/S2213-2600(22)00360-5\u003c/li\u003e\n\u003cli\u003eWorld Health Organization. WHO roadmap on uses of COVID-19 vaccines in the context of Omicron and high population immunity. Available from: https://iris.who.int/handle/10665/373987\u003c/li\u003e\n\u003cli\u003eCiapponi A, Berrueta M, Argento FJ, Ballivian J, Bardach A, Brizuela ME, et al. Safety and effectiveness of COVID-19 vaccines during pregnancy: a living systematic review and meta-analysis. Drug Saf. 2024;47(10):991\u0026ndash;1010. doi:10.1007/s40264-024-01458-w\u003c/li\u003e\n\u003cli\u003eWorld Health Organization. WHO COVID-19 dashboard. Available from: https://data.who.int/dashboards/covid19/variants\u003c/li\u003e\n\u003cli\u003eFeldstein LR, Ruffin J, Wiegand RE, Borkowf CB, James-Gist J, Babu TM, et al. Effectiveness of mRNA COVID-19 vaccines and hybrid immunity in preventing SARS-CoV-2 infection and symptomatic COVID-19 among adults in the United States. J Infect Dis. 2025;231(4):e743\u0026ndash;e753. doi:10.1093/infdis/jiaf007\u003c/li\u003e\n\u003c/ol\u003e"},{"header":"Table 1","content":"\u003cp\u003eTable 1 is available in the Supplementary Files section.\u003c/p\u003e\n"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"bmc-global-and-public-health","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"","sideBox":"Learn more about [BMC Global and Public Health](https://bmcglobalpublichealth.biomedcentral.com/)","snPcode":"44263","submissionUrl":"https://submission.springernature.com/new-submission/44263/3","title":"BMC Global and Public Health","twitterHandle":"@BMC_GPH","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"COVID-19, Omicron, pregnancy complications, pregnancy outcomes, maternal health, neonatal outcomes, cohort study","lastPublishedDoi":"10.21203/rs.3.rs-7933142/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7933142/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cb\u003eBackground\u003c/b\u003e\u003c/p\u003e\u003cp\u003eOur aim was to determine if SARS-CoV-2 infection during pregnancy increased the risk of adverse maternal, perinatal, neonatal, or postpartum outcomes during pre-Omicron and Omicron periods.\u003c/p\u003e\u003cp\u003e\u003cb\u003eMethods\u003c/b\u003e\u003c/p\u003e\u003cp\u003eWe conducted a prospective cohort study across 43 health facilities, in 10 predominantly primarily low- and middle-income countries, comprising mainly maternity, public and private hospitals in rural and urban areas. A total of 16,007 pregnant women were consecutively recruited between January 2021 and October 2023 (75% in pre-Omicron period and 25% in Omicron period), followed from enrollment through delivery and to six weeks postpartum. The main outcomes are: miscarriage, haemorrhage, preeclampsia/eclampsia, hypertensive disorders of pregnancy, thromboembolic disease, preterm labour, placental abruption, near-miss at delivery, Cesarean delivery, maternal death, modified maternal morbidity and mortality index (MMMI); stillbirth, preterm birth, low birth weight, congenital anomalies, NICU admission, perinatal death, severe perinatal morbidity and mortality index (SPMMI); haemorrhage, infection, or readmission to hospital during postpartum period.\u003c/p\u003e\u003cp\u003e\u003cb\u003eResults\u003c/b\u003e\u003c/p\u003e\u003cp\u003eBased on RT-PCR or antigen testing at enrolment and serial serologic testing, 2,189 participants had confirmed SARS-CoV-2 infection during pregnancy, 116 were classified as probable infection, 7,332 as possible infection, 402 participants were considered probably uninfected, 1,053 had no evidence of infection, and 4,915 had unknown infection status. During the pre-Omicron era, the risk of several outcomes was significantly higher among the infected group compared to those uninfected: emergency Cesarean delivery (RR 1.26, CI 1.03\u0026ndash;1.53); MMMI (RR 1.27, CI 1.12\u0026ndash;1.44), preterm birth\u0026thinsp;\u0026lt;\u0026thinsp;37 weeks (RR 1.73, CI 1.32\u0026ndash;2.28), \u0026lt;\u0026thinsp;34 weeks (RR 3.69, CI 1.92\u0026ndash;7.09), \u0026lt;\u0026thinsp;32 weeks (RR 7.58, CI 2.19\u0026ndash;26.19), NICU admission (RR 1.90, CI 1.28\u0026ndash;2.82) and SPMMI (RR 1.76, CI 1.01\u0026ndash;3.05). During the Omicron era, the only outcome with a significantly elevated risk was preterm birth\u0026thinsp;\u0026lt;\u0026thinsp;34 weeks (RR 1.88, CI 1.04\u0026ndash;3.39).\u003c/p\u003e\u003cp\u003e\u003cb\u003eConclusions\u003c/b\u003e\u003c/p\u003e\u003cp\u003eSARS-CoV-2 infection during pregnancy was associated with an increased risk of several adverse maternal, perinatal, and neonatal outcomes, particularly in the pre-Omicron era. These risks were largely attenuated during the Omicron period; however, the persistent elevated risk for preterm birth\u0026thinsp;\u0026lt;\u0026thinsp;34 weeks gestation underscores the need for updated evidence on SARS-CoV-2 infection and pregnancy outcomes, especially in relation to emerging Omicron sub-variants.\u003c/p\u003e","manuscriptTitle":"Maternal, perinatal, neonatal, and postpartum outcomes following SARS-CoV-2 infection in pregnancy: A WHO multi-country prospective cohort study ","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-11-18 08:47:52","doi":"10.21203/rs.3.rs-7933142/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2026-01-12T14:23:28+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-01-08T08:36:51+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-01-03T10:03:17+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"280829969948128344043158687848510916765","date":"2025-12-31T11:57:52+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"35792905457195322860249857118135001677","date":"2025-12-31T07:25:00+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-12-11T19:59:17+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"199669530644445659724099891322301746594","date":"2025-12-03T17:54:45+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-11-16T21:29:44+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"183068907106760355806339373332989283156","date":"2025-11-08T10:13:50+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-11-06T18:50:39+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-10-24T05:19:15+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-10-24T05:07:02+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Global and Public Health","date":"2025-10-23T14:21:01+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-global-and-public-health","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"","sideBox":"Learn more about [BMC Global and Public Health](https://bmcglobalpublichealth.biomedcentral.com/)","snPcode":"44263","submissionUrl":"https://submission.springernature.com/new-submission/44263/3","title":"BMC Global and Public Health","twitterHandle":"@BMC_GPH","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"dd933300-4b8b-4461-b12e-8fd888c385c1","owner":[],"postedDate":"November 18th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2026-05-19T15:23:31+00:00","versionOfRecord":[],"versionCreatedAt":"2025-11-18 08:47:52","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-7933142","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7933142","identity":"rs-7933142","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}