Timing matters: Unveiling the distinct effects of early- versus late-onset pre-eclampsia on mothers and newborns in a tertiary hospital in Bangladesh

Background: Pre-eclampsia (PE) is a significant cause of maternal and perinatal morbidity and mortality worldwide. The clinical course and severity of PE can vary depending on the gestational age at onset. However, limited data from developing countries including Bangladesh stratify outcomes by onset timing, hindering context-specific management. This study aimed to differentiate maternal . CC-BY 4.0 International licenseIt is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review) The copyright holder for this preprint this version posted October 17, 2025. ; https://doi.org/10.1101/2025.10.15.25337483doi: medRxiv preprint NOTE: This preprint reports new research that has not been certified by peer review and should not be used to guide clinical practice. 2 and perinatal outcomes associated with early-onset PE (EO-PE, <34 weeks) versus late-onset PE (LO-PE, ≥ 34 weeks) in a tertiary care setting in Bangladesh.

A cross-sectional study was conducted at Faridpur Medical College Hospital, Faridpur, Bangladesh, from March to August 2023. Data were collected from hospital records and through pre-structured telephone questionnaires for 255 mothers diagnosed with PE (EO-PE: n=121; LO-PE: n=134). Maternal, fetal and neonatal outcomes were compared between the EO-PE and LO-PE groups.

The prevalence of PE among admitted pregnant women was 11.28%. EO-PE was associated with more adverse perinatal outcomes compared to LO-PE, including lower fetal survival (72% vs 97%), higher rates of prematurity (76% vs 13%), low birth weight (74% vs 18%), and increased need for neonatal hospital admission (54% vs 21%) (p<0.001). Maternal complications such as eclampsia (31% vs 19%, p=0.018) and placental abruption (20% vs 10%, p=0.022) were more frequent in the EO-PE group. However, cesarean section rates were higher in the LO-PE group (p<0.001).

Early-onset PE is associated with more severe adverse maternal and perinatal outcomes compared to late-onset PE. Early screening, health education, and specialized management protocols for EO-PE group could be effective in mitigating associated complications.

Developing Countries, Perinatal Death, Pre-eclampsia, Pregnancy Complications, Pregnancy Outcome. . CC-BY 4.0 International licenseIt is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review) The copyright holder for this preprint this version posted October 17, 2025. ; https://doi.org/10.1101/2025.10.15.25337483doi: medRxiv preprint 3 MAIN TEXT 1. Introduction Pregnancy, while a transformative phase in a woman's life, can be complicated by conditions that pose significant risks to both mother and child 1. Hypertensive disorders of pregnancy, particularly pre-eclampsia (PE), are major contributors to maternal and perinatal morbidity and mortality globally 2. PE is typically characterized by new-onset hypertension after 20 weeks of gestation accompanied by proteinuria or other evidence of maternal end-organ or uteroplacental dysfunction 3. It affects an estimated 2% to 10% of pregnancies worldwide, with 20% of the total global PE patients belong to the underdeveloped nations 2, 4. The burden of PE is disproportionately high in developing countries, which may range from 2% to 17% due to challenges in healthcare infrastructure and management of complications 5, 6. Bangladesh has made significant progress in reducing overall maternal mortality in recent decades. However, the prevalence of PE is 14.4% in Bangladesh which is much higher compared to the global percentage 7. According to Bangladesh Maternal Mortality and Health Care Surveys (BMMSs) 2016, the preeclampsia/eclampsia-specific mortality ratio was 46 per 100,000 live births, 8. Moreover, 9% of stillbirths and 7% of early neonatal deaths in Bangladesh was attributed to eclampsia, the severe progression of PE 9. PE remains a formidable challenge, accounting for nearly one-fourth of all maternal deaths and ranking as the second most common direct cause of maternal mortality in Bangladesh 8. . CC-BY 4.0 International licenseIt is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review) The copyright holder for this preprint this version posted October 17, 2025. ; https://doi.org/10.1101/2025.10.15.25337483doi: medRxiv preprint 4 The classification of PE into early-onset (EO-PE, typically occurring <34 weeks of gestation) and late-onset (LO-PE, occurring ≥ 34 weeks of gestation) has gained prominence due to its significant prognostic implications 10, 11. EO-PE is often associated with more severe underlying placental pathology, leading to more severe clinical manifestations and poorer outcomes for both mother and fetus compared to LO-PE 12, 13. Understanding these distinctions is critical for risk stratification, targeted interventions, and optimizing resource allocation. Despite the recognized importance of this classification, there is a relative scarcity of studies directly comparing maternal and fetal outcomes between EO-PE and LO-PE groups within the context of Bangladesh and other developing countries. Existing local data do not stratify by onset timing, limiting the ability to tailor management strategies effectively. A better understanding of PE, including its varying clinical presentations and outcomes based on the timing of onset, is essential for improving maternal and perinatal health. Therefore, this study aimed to compare the maternal, fetal, and neonatal outcomes of early versus late-onset PE among women managed at a tertiary referral hospital in Faridpur, Bangladesh. 2. Methods 2.1 Study Design and Setting This cross-sectional study was conducted at the Department of Obstetrics and Gynecology, Faridpur Medical College Hospital (FMCH) in Faridpur, Bangladesh. FMCH is a tertiary level hospital serving as a major referral center for public and . CC-BY 4.0 International licenseIt is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review) The copyright holder for this preprint this version posted October 17, 2025. ; https://doi.org/10.1101/2025.10.15.25337483doi: medRxiv preprint 5 private hospitals in Faridpur and adjacent districts including Rajbari, Gopalganj, Magura, and Madaripur. 2.2 Study Population and Sampling We reviewed hospital admission records of all pregnant women admitted and delivered at FMCH between March 2023 and August 2023. Women diagnosed with PE according to the American College of Obstetricians and Gynecologists (ACOG) guidelines were considered eligible 3. Inclusion criteria for participants were: women of reproductive age ranging between 18-45 years, a complete hospital record (including pregnancy, delivery, and neonatal details) and availability of contact information for follow-up. Patients whose pregnancy with PE was terminated before the age of fetal viability (defined as <28 weeks of gestation) and those without significant hospital record data or unavailable contact information were excluded. PE was categorized as early-onset (EO-PE) if diagnosed before 34 completed weeks of gestation and late-onset (LO- PE) if diagnosed at or after 34 completed weeks of gestation 10. 2.3 Data Collection Socio-demographic information (e.g., age, education, occupation, residence, religion), and other clinical history were collected through telephone interviews. Clinical information, including antenatal care (ANC) and obstetric history, pregnancy complications, maternal outcome, were primarily extracted from hospital medical records using a standardized data abstraction form. Fetal and neonatal . CC-BY 4.0 International licenseIt is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review) The copyright holder for this preprint this version posted October 17, 2025. ; https://doi.org/10.1101/2025.10.15.25337483doi: medRxiv preprint 6 outcomes such as prematurity, low birth weight (LBW), Intrauterine Growth Restriction (IUGR), congenital anomalies, Apgar scores, need for hospital admission, respiratory support, neonatal death were also collected from the records. The data collection was conducted by two trained data collectors using a pre-structured and pre-tested questionnaire. 2.4 Data Analysis Collected data were rechecked for errors and cleaned using Microsoft Excel (version 16.72). Statistical analysis was performed using STATA version 14.2 (StataCorp, College Station, Texas, USA). Descriptive statistics were used to summarize participant characteristics. Categorical data were presented as frequencies and percentages, and comparisons between EO-PE and LO-PE groups were made using the Chi-square test or Fisher's exact test where appropriate. Continuous data were presented as mean ± standard deviation (SD), and comparisons were made using the independent samples t-test. A p-value <0.05 was considered statistically significant. 2.5 Ethical Considerations Ethical approval for this study was obtained from the Institutional Review Board (IRB) of Faridpur Medical College Hospital, Faridpur. Informed verbal consent was obtained from participants prior to conducting the telephone interviews. All data collected were anonymized prior to analysis. . CC-BY 4.0 International licenseIt is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review) The copyright holder for this preprint this version posted October 17, 2025. ; https://doi.org/10.1101/2025.10.15.25337483doi: medRxiv preprint 7 3. Results 3.1 Participant Recruitment and Baseline Characteristics During the six-month study period (March to August 2023), a total of 3785 pregnant women were delivered at the Department of Gynaecology and Obstetrics, FMCH, Faridpur. Among them, 427 (11%) mothers were diagnosed with PE. 89 cases were excluded due to the unavailability of significant clinical records, and an additional 41 cases were excluded as our data collectors were unable to contact them. From the eligible cases, 255 women with PE agreed to participate and provide further information. This final sample comprised 121 women in the EO-PE group and 134 women in the LO-PE group. (Figure 1) Figure 1: Flowchart of participant selection from admitted pre-eclamptic patients . CC-BY 4.0 International licenseIt is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review) The copyright holder for this preprint this version posted October 17, 2025. ; https://doi.org/10.1101/2025.10.15.25337483doi: medRxiv preprint 8 The mean age of the patients was 26.48 ± 6.02 years, with women in the EO- PE group being older in age compared to the LO-PE group (27.85 ± 5.63 years vs 25.18 ± 6.10 years, p=0.003). While the majority of participants had attained only up to primary level education, the overall educational level was significantly higher in the LO-PE group (p=0.016). Approximately 80% of participants were homemakers. However, being a student was significantly more common in the LO- PE group compared to the EO-PE group (15.67% vs. 8.26%, p=0.03). About 95% of participants were Muslim, and approximately two-thirds resided in rural areas, with no significant difference between groups. A significantly higher percentage of women in the EO-PE group resided outside Faridpur district compared to the LO- PE group (62.81% vs. 44.03%, p=0.003). (Table 1) Table-1: Comparison of socio-demographic factors between EO-PE & LO-PE groups Characteristics EO-PE (n=121) LO-PE (n=134) P-value Frequency Percentage Frequency Percentage Age (Mean ± SD) 27.85 ± 5.63 25.18 ± 6.10 0.003* Education Level: 0.016* - Illiterate 11 9.09 % 9 6.72 % - Able to read/write 18 14.88 % 6 4.48 % - Primary 45 37.19 % 44 32.84 % - Secondary 16 13.22 % 30 22.39 % - Undergraduate 23 19.01 % 27 20.15 % - Graduate & above 8 6.61 % 18 13.43 % Occupation: 0.03* . CC-BY 4.0 International licenseIt is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review) The copyright holder for this preprint this version posted October 17, 2025. ; https://doi.org/10.1101/2025.10.15.25337483doi: medRxiv preprint 9 - Homemaker 101 83.47 % 105 78.36 % - Business 8 6.61 % 2 1.49 % - Student 10 8.26 % 21 15.67 % - Service holder 2 1.65 % 6 4.48 % Religion: 0.455 - Islam 113 93.39 % 128 95.52 % - Hinduism 8 6.61 % 6 4.48 % Residence: 0.003* - In Faridpur district 45 37.19 % 75 55.97 % - Outside Faridpur 76 62.81 % 59 44.03 % Living Area: 0.731 - Rural 88 72.73 % 100 74.63 % - Urban 33 27.27 % 34 26.27 % * P-value <0.05 – statistically significant. 3.2 Maternal Clinical History and ANC A significantly higher proportion of the EO-PE women were primigravid compared to the LO-PE group (76.03% vs. 47.76%, p<0.001). Pre-existing chronic hypertension (14.88% vs 5.97%, p=0.019) and hypothyroidism (14.05% vs. 1.49%, p<0.001) had significantly higher prevalence in the EO-PE group as well. There were no significant differences between groups in the prevalence of gestational diabetes mellitus or a family history of hypertension. Regarding ANC, more than half of all participants did not complete the minimum recommended four ANC visits. There was no significant difference in achieving ≥ 4 ANC visits between the LO-PE group and the EO-PE group (44.78% . CC-BY 4.0 International licenseIt is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review) The copyright holder for this preprint this version posted October 17, 2025. ; https://doi.org/10.1101/2025.10.15.25337483doi: medRxiv preprint 10 vs. 35.54%, p=0.277). Similarly, no significant difference was observed in the history of PE in previous pregnancies among multigravida women (17.39% vs. 12.50%, p=0.405). (Table 2) Table 2: Comparison of clinical characteristics between the EO-PE and LO-PE groups Characteristics EO-PE (n=121) LO-PE (n=134) P-value Frequency Percentage Frequency Percentage Primigravida 92 76.03 % 64 47.76 % <0.001* Gestational Diabetes Mellitus 8 6.61 % 8 5.97 % 0.833 Hypothyroidism 17 14.05 % 2 1.49 % <0.001* Chronic Hypertension 18 14.88 % 8 5.97 % 0.019* History of PE in previous pregnancies 16 (n= 92) 17.39 % 8 (n=64) 12.50 % 0.405 Family history of Hypertension 48 39.67 % 51 38.06 % 0.792 ANC (Minimum 4 visits) 43 35.54 % 60 44.78 % 0.277 * P-value <0.05 – statistically significant. 3.3 Maternal Outcomes and Complications Maternal mortality did not differ significantly between the groups (3.31% in EO-PE vs. 1.49% in LO-PE, p=0.340). However, specific maternal complications were more frequent in the EO-PE group. PE progressed to eclampsia in 31.40% of EO- PE cases compared to 18.66% in LO-PE cases (p=0.018). Placental abruption was also more common in the EO-PE group (19.83% vs 9.70%, p=0.022). The . CC-BY 4.0 International licenseIt is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review) The copyright holder for this preprint this version posted October 17, 2025. ; https://doi.org/10.1101/2025.10.15.25337483doi: medRxiv preprint 11 occurrence of other severe maternal complications such as HELLP syndrome, postpartum hemorrhage (PPH), acute kidney injury (AKI), cerebrovascular accidents or pulmonary edema had no significant differences between the groups. The overall prevalence of adverse maternal outcome (defined as one or more maternal complications or maternal death) was slightly higher in the EO-PE group (47.11%) compared to the LO-PE group (44.78%, p=0.709). Interestingly, women in the LO-PE group had a significantly higher rate of cesarean sections (C/S) compared to those in the EO-PE group (84.33% vs 51.24%, p<0.001). (Table 3) Table 3: Comparison of maternal outcomes between the EO-PE and LO-PE groups Characteristics EO-PE (n=121) LO-PE (n=134) p value Frequency Percentage Frequency Percentage Mode of delivery: - NVD 59 48.76 % 21 15.67 % <0.001* - C/S 62 51.24 % 113 84.33 % Maternal outcome: - Maternal death 4 3.31 % 2 1.49 % 0.340 Complications: Eclampsia 38 31.40 % 25 18.66 % 0.018* HELLP Syndrome 10 8.26 % 10 7.46 % 0.812 Abruptio Placenta 24 19.83 % 13 9.70 % 0.022* Postpartum hemorrhage 6 4.96 % 12 8.96 % 0.213 Acute Kidney Injury 4 3.31 % 2 1.49 % 0.340 Cerebrovascular accidents 8 6.61 % 8 5.97 % 0.833 Pulmonary edema 8 6.61 % 4 2.99 % 0.172 . CC-BY 4.0 International licenseIt is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review) The copyright holder for this preprint this version posted October 17, 2025. ; https://doi.org/10.1101/2025.10.15.25337483doi: medRxiv preprint 12 Maternal adverse outcome a 57 47.11 % 60 44.78 % 0.709 * P-value <0.05 – statistically significant. a Maternal adverse outcome was defined as occurrence of one or more maternal complications or maternal death. 3.4 Fetal and Neonatal Outcomes The EO-PE group experienced significantly poorer fetal outcomes. Fetal survival (resulting in a livebirth) was markedly lower in the EO-PE group (72%; 87 livebirths out of 121 cases) compared to the LO-PE group (97%; 130 livebirths out of 134 cases, p<0.001). The sex distribution of infants did not differ significantly between the groups. (Table 4) Table 4: Comparison of fetal outcomes between the EO-PE and LO-PE groups Characteristics EO-PE (n=121) LO-PE (n=134) P-value Frequency Percentage Frequency Percentage Fetal outcome: <0.001* - Livebirth 87 71.90 % 130 97.01 % - Stillbirth 34 28.10 % 4 2.99 % Baby Sex: 0.200 - Male 58 47.93 % 75 55.97 % - Female 63 52.07 % 59 44.03 % * P-value <0.05 – statistically significant. . CC-BY 4.0 International licenseIt is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review) The copyright holder for this preprint this version posted October 17, 2025. ; https://doi.org/10.1101/2025.10.15.25337483doi: medRxiv preprint 13 In terms of neonatal outcomes, those born to mothers with EO-PE had substantially worse outcomes. Women in the EO-PE group (75.86%) had five times more premature (<37 weeks) deliveries compared to the LO-PE group (13.07%, p<0.001). Similarly, low birth weight babies (<2500g) were about four times more frequent in the EO-PE group (73.56%) than in the LO-PE group (17.69%, p<0.001). IUGR was also significantly more common in neonates from the EO-PE group (29.89% vs 14.62%, p=0.007). The need for neonatal hospital admission was significantly higher for neonates in the EO-PE group compared to the LO-PE group (54.02% vs. 20.77%, p<0.001). Neonatal death occurred significantly more often in the EO-PE group (11 deaths, 12.64%) compared to the LO-PE group (2 deaths, 1.54%, p=0.001). The difference in the proportion of neonates with a 5-minute Apgar score and the number of cases of congenital anomalies between the EO-PE and LO-PE groups was not significant. Overall, the neonatal adverse outcome (defined as the occurrence of at least one or more neonatal complications or neonatal death) was alarmingly higher in the EO-PE group compared to the LO-PE group (89.66% vs. 25.38%, p<0.001). (Table 5) Table 5: Comparison of neonatal outcomes between the EO-PE and LO-PE groups Characteristics EO-PE (n=87) LO-PE (n=130) P-value Frequency Percentage Frequency Percentage Prematurity (<37 weeks) 66 75.86 % 17 13.07 % <0.001* LBW (<2500 g) 64 73.56 % 23 17.69 % <0.001* . CC-BY 4.0 International licenseIt is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review) The copyright holder for this preprint this version posted October 17, 2025. ; https://doi.org/10.1101/2025.10.15.25337483doi: medRxiv preprint 14 IUGR 26 29.89 % 19 14.62 % 0.007* Congenital Anomaly 0 0.00 % 4 3.08 % 0.099 Hospital Admission 47 54.02 % 27 20.77 % <0.001* 5-minute APGAR Score <7 12 13.79 % 10 7.69 % 0.145 Neonatal Death 11 12.64 % 2 1.54 % 0.001* Neonatal adverse outcome a 78 89.66 % 33 25.38 % <0.001* * P-value <0.05 – statistically significant. a Neonatal adverse outcome was defined as the occurrence of one or more neonatal complications or neonatal death. 4. Discussion This study showed that early-onset PE was associated with more severe maternal complications such as eclampsia and placental abruption, and substantially worse perinatal outcomes including higher rates of stillbirth, prematurity, low birth weight and neonatal mortality. Our findings align with previous research suggesting that early-onset PE (EO-PE) represents a more severe form of the disorder 12-15. The observed prevalence of PE (11.28%) among admitted pregnant women in our study is consistent with reports from some other studies in the region. Recent facility-based studies in Nepal and Bangladesh reported the prevalence of PE as 12% and 14% respectively 16, 17. This high prevalence in tertiary centers is likely indicative of referral bias, where complicated cases are disproportionately represented. Such tertiary centers should be adequately resourced with . CC-BY 4.0 International licenseIt is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review) The copyright holder for this preprint this version posted October 17, 2025. ; https://doi.org/10.1101/2025.10.15.25337483doi: medRxiv preprint 15 specialized personnel and infrastructure to handle the high volume of these patients. Studies have consistently shown that women with EO-PE have a higher incidence of severe maternal complications 18-20. In our study, EO-PE was associated with significantly higher rates of eclampsia and placental abruption. Similarly, a study in India found higher rates of eclampsia (43% vs. 28%) and abruptio placentae (14.4% vs. 12%) in the EO-PE group compared to the LO-PE group 21 The underlying cause of these poor outcomes lies in the defective placentation that occurs early in pregnancy, leading to inadequate spiral artery remodeling, uteroplacental ischemia, and a surge of anti-angiogenic factors into the maternal bloodstream 13, 22. These factors contribute to widespread endothelial dysfunction. Given its severity, EO-PE should be treated as a high-risk condition that requires close monitoring and care in specialized settings. Improving early screening and educating women about warning signs during pregnancy could help reduce serious maternal complications. Interestingly, our study found a significantly higher rate of Cesarean sections in the LO-PE group. This contrasts with some studies that show no difference or higher rates in EO-PE due to urgency [17,19]. The difference observed in our study may be influenced by local clinical practices and the specific thresholds used for obstetric interventions, such as decisions around the mode and timing of delivery. This highlights the need for clear institutional guidelines for the timing and mode of delivery in both PE phenotypes. . CC-BY 4.0 International licenseIt is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review) The copyright holder for this preprint this version posted October 17, 2025. ; https://doi.org/10.1101/2025.10.15.25337483doi: medRxiv preprint 16 This study reported that EO-PE was associated with poorer fetal survival and increased rates of prematurity, low birth weight, IUGR and neonatal death. These adverse neonatal outcomes reflect the severe uteroplacental insufficiency characteristic of EO-PE, where the placenta fails to develop properly early in pregnancy 13. As a result, it cannot provide adequate oxygen and nutrients to the fetus 23. This dysfunctional placenta poses serious risks to both the baby and the mother. To protect the mother’s health, doctors often need to deliver the baby prematurely through iatrogenic preterm birth. While this can be life-saving for the mother, it results in neonatal prematurity and its associated complications such as breathing difficulties, feeding problems, and long-term disability 24, 25. This pathophysiology justifies the higher rate of hospitalization and neonatal mortality among children born to mothers with EO-PE, which was also observed in our study. Management of these cases must occur exclusively in integrated tertiary centers with a Neonatal Intensive Care Unit (NICU). Additionally, specialized training should be facilitated for healthcare providers for a better maternal and neonatal outcome. To the best of our knowledge, this is the first study from Bangladesh to compare pregnancy outcomes based on the timing of pre-eclampsia onset. An additional strength lies in the comprehensive evaluation of maternal, fetal, and neonatal outcomes, enabling a multidimensional understanding of the clinical burden associated with PE. However, several limitations must be acknowledged. First, being a single facility based study, the findings may be subject to referral bias and may not be generalizable to the broader pregnant population in Bangladesh. . CC-BY 4.0 International licenseIt is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review) The copyright holder for this preprint this version posted October 17, 2025. ; https://doi.org/10.1101/2025.10.15.25337483doi: medRxiv preprint 17 Second, the sample size may have been insufficient to detect significant differences for less common maternal complications. Third, the collection of socio- demographic and family history data via phone interview introduces potential for recall bias, although a pre-structured questionnaire was used to standardize this process. Future research should include larger, multi-center prospective studies with adjustment for confounders to further delineate these differences and explore underlying pathophysiological mechanisms. Longitudinal studies are also needed to understand the long-term health consequences of EO-PE and LO-PE for both mothers and their children. 5. Conclusion This study showed that the timing of PE onset has distinct implications for both maternal and perinatal outcomes in a tertiary level hospital setting in Bangladesh. EO-PE showed more adverse maternal and perinatal outcomes. This group is highly vulnerable and requires close monitoring in well-equipped facilities. Focus should be given on early screening, health education, and training of the healthcare providers. Further longitudinal research should be carried out in order to gain a better understanding of the differential impact of early versus late PE.

The authors gratefully acknowledge the Department of Obstetrics & Gynaecology at Faridpur Medical College Hospital (FMCH) for their invaluable support in providing patient records for this study. . CC-BY 4.0 International licenseIt is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review) The copyright holder for this preprint this version posted October 17, 2025. ; https://doi.org/10.1101/2025.10.15.25337483doi: medRxiv preprint 18

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