Influence of the delivery mode on the short-term outcomes of extremely preterm infants

Influence of the delivery mode on the short-term outcomes of extremely preterm infants | 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 Influence of the delivery mode on the short-term outcomes of extremely preterm infants Qianmeng Huang, Jie Wu, Rongyue Wang This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-3790520/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Objective: To study the influence of the delivery mode on the short-term outcomes of extremely preterm infants, and to provide a basis for delivery mode selection. Methods: A total of 166 extremely preterm infants who were born from 2018 to 2022 were enrolled. According to the delivery mode, they were divided into two groups: natural birth group ( N = 103 ) and caesarean birth group ( N = 63 ) . A statistical analysis was performed for maternal data and short-term outcomes. Results: Compared with the caesarean birth group, the natural birth group had significantly higher incidence rates of early-onset sepsis and necrotizing enterocolitis ( NEC ) ( P ＜0.05 ) . The logistic regression analysis showed that natural birth was an independent risk factor for early-onset sepsis and NEC ( OR = 2.032 and 2.731 respectively， P ＜0.05 ) , and the gestational diabetes was an independent risk factor for NEC. Conclusions: Caesarean birth decreased the incidence of early-onset sepsis and NEC in extremely premature infants and did not decrease the incidence rates of other adverse outcomes. Delivery mode Sepsis Necrotizing enterocolitis Prognosis Extremely preterm infant Introduction Extremely preterm birth ( EPI ), defined as birth before 28 weeks of gestation, is 5% in preterm birth 1,2 . With extensive use of assisted reproduction technologies, increased high risk pregnancies and development of premature infants treatment, the EPI is rising in recent years 3 . Preterm birth is a major cause of perinatal and neonatal mortality as well as of short-and long-term morbidity in addition to birth defects. Due to prematurity, they suffer higher incidence rate in necrotizing enterocolitis, intraventricular hemorrhage, retinopathy of prematurity, infection and so on 4,5 . It is well known that the infants born at the lowest gestational ages have the worst outcome. The infants’ immaturity has been hypothesized to be the primary reason for this. As survival increases at earlier gestational ages, the best mode of delivery is of increasing importance. The optimal delivery mode of EPI is a debatable point. Some studies 6–8 showed that caesarean section was associated with a significant reduction of the perinatal mortality and morbidity of premature infants. However, other scholars 9,10 did not find a difference in neonatal morbidity or mortality between two groups. As the number of cases tends to be small, reports about the influence of the delivery mode on the outcomes of extremely preterm infants are relatively rare at present. The purpose of this study was to examine whether mode of delivery is associated with perinatal mortality and morbidity of extremely premature infants, and to help clinical treatment decision-making process. Material and methods 1. Study population This study included 166 EPI born between 1 January 2018 and 31 December 2022 in the Second Affiliated Hospital of Wenzhou Medical University. Consents were obtained from legal guardians of all subjects. Inclusive criteria: (1). Transferred to neonatal intensive care units ( NICUs ) after birth; (2). Born at 24-28 weeks’ gestation; (3). singleton. Exclusion criteria: (1). Gave up treatment because of personal reasons; (2). Suffered from Serious congenital illnesses, such as complex congenital heart disease, chromosome abnormality, etc; (3). Twins or multiples. According to the delivery mode, they were divided into two groups: natural birth group and caesarean birth group. Ethics approval was obtained from hospital ethics committees, as required by national legislation. 2. Data colletion (1) Maternal age; Gestational diabetes; Hypertensive disorder complicating pregnancy; Chorioamnionitis; Prenatal interventions [ Steroid administration ( pregnant women received adequate treatment of dexamethasone before delivering ) , Prophylactic antibiotic administration ( pregnant women received antibiotic therapy before delivering, and the interval between the treatment and delivery was 4 hours or longer ) , Magnesium sulfate administration ] . (2) Delivery mode; Gestational week; Birth weight; Apgar score ≤3 at 1 min; Early-onset sepsis ( EOS ) ; Late-onset sepsis ( LOS ) ; Intraventricular hemorrhage ( IVH ) ; periventricular leukomalacia ( PVL ) ; retinopathy of prematurity ( ROP ) ; necrotizing enterocolitis ( NEC ) ; hemodynamically significant ductus arteriosus ( hsPDA ) ; Neonatal death ( neonatal died in the hospital or died in the short time after treatment abandonment ) . 3. Perinatal outcomes Main adverse outcomes: Neonatal death; Early-onset sepsis, Late-onset sepsis, EOS occured within 7days, as opposed to LOS, which was beyond 7days; NEC ≥ 3, The criteria utilized in our survey for the diagnosis of NEC and for grading the severity of disease were based on Bell’s stage 11 . Secondary adverse outcomes: Intraventricular hemorrhage grade 3 or higher ( IVH ≥ 3) , graded according to Papile et al 12 ; Periventricular leukomalacia, defined according to de Vries et al 13 ; Retinopathy of prematurity stage 3 or higher ( ROP ≥ 3 ) , defined according to the International Classification of Retinopathy of Prematurity 14 ; hsPDA; Apgar score ≤3 at 1 min. 4. Statistical analysis All statistical analyses were performed using SPSS 20.0. Continuous variables were shown as means ± standard deviation ( SD ) , which were analyzed using t -tests. Categorical variables were presented as rates and odds ratio with 95% confidence intervals ( CI ) , which were analyzed using Chi-square tests. Logistic regression were used to analyze the risk factors of survival in preterm infants. A p -value < 0.05 was considered statistically significant. Results 1. Demographics of EPI and mothers During the 5-year study, in total, 166 EP infants were enrolled. According to the delivery mode, they were divided into two groups: natural birth group ( N =103 ) and caesarean birth group ( N = 63 ) . The incidence of chorioamnionitis and prophylactic antibiotic exposure prior to delivery in natural birth group were higher than that in caesarean birth group ( P ＜0.05 ) . The hypertensive disorder occurring rate and gestational age were significantly lower in natural birth group than in caesarean birth group ( P ＜0.05 ) . All other baseline characteristics including maternal age at delivery, incidence of gestational diabetes, glucocorticoid and magnesium sulfate exposure prior to delivery and birth weight were not significantly different between the two groups ( P ＞0.05 ) . The maternal and renatal characterictics are shown in table1. 2. Adverse outcomes of EP infants The incidence of neonatal death, early-onset sepsis, late-onset sepsis, NEC, IVH ≥ 3/ PVL, ROP ≥ 3, hsPDA, Apgar score ≤ 3 at 1 min was repectively 12.7% ( 21 of 166 ) , 33.1 % ( 55 of 166 ) , 21.1% ( 35 of 166 ) , 17.5% ( 29 of 166 ) , 25.9% ( 43 of 166 ) , 4.8% ( 8 of 166 ) , 9% ( 15 of 166 ) , 7.2% ( 12 of 166 ) . In the natural birth group, there was an increased risk for main adverse outcomes, early-onset sepsis and NEC ( P ＜0.05 ) . There were no significant difference in incidence of neonatal death and late-onset sepsis between two groups ( P ＞0.05 ) . No significant differences were found between natural birth group and caesarean birth group regarding secondary adverse outcomes including IVH ≥ 3 / PVL, ROP ≥ 3, hsPDA and Apgar score ≤ 3 at 1 min ( P ＞0.05 ) . The adverse outcomes of EP infants are shown in table 2. 3. Logistic regression analysis of risk factors for adverse outcomes We made logistic regression analysis by taking EOS and NEC as dependent variable and taking delivery mode, gestational diabetes, hypertensive disorder, Chorioamnionitis, glucocorticoid, prophylactic antibiotic and magnesium sulfate exposure prior to delivery as independent variable. The logistic regression analysis indicated that natural birth was an independent risk factor for early-onset sepsis and NEC ( OR = 2.032 and 2.731 respectively， P ＜0.05 ) ( Table 3 and Table 4 ) , and the gestational diabetes was an independent risk factor for NEC ( OR = 2.876， P ＜0.05 ) ( Table 4 ) . Discussion With economic growth, social progress and improvements in medicine, the preterm birth has become an important issue. We need to make more efforts to decrease mortality and improve short-term and long-term prognosis of extremely premature infants. There are many reasons to choose caesarean section in the case of extremely premature delivery, including maternal complications, fetal distress, placenta abruption, fetal malposition and so on. EP infants are at higher risk of morbidity and mortality owing to extreme immaturity 15,16 . Whether caesarean birth will reduce the risk of morbidity and mortality approaches the focus of attention more and more. NEC is common digestive emergency in EP infants which may cause gastrointestinal perforation, prolong hospitalization time and increase the risk of neonatal death 17–19 . Yee, Ris, et al. 20,21 reported that caesarean birth had no significant effect on NEC. While others 22–24 reported that caesarean birth was associated with decreased risk of NEC. Luig, et al. 25 reported that caesarean birth did not significantly affect the risk of NEC in preterm infants born between 24 and 27 weeks GA, but was associated with a significantly increased risk in those born between 28 and 31 weeks GA. In our study, the natural birth group had significantly higher incidence rates of necrotizing enterocolitis( 22.3% vs 9.5% ). The logistic regression analysis indicated that natural birth was an independent risk factor for NEC. When the fetus is in hypoxic distress, the blood in the body will be redistributed, and the blood vessels such as intestinal mucosa will contract strongly, so that more blood will be supplied to important organs such as the heart and brain, which will then lead to a sharp decline in the blood supply of the gastrointestinal tract, ischemia injury of the intestinal mucosa, and induce NEC 23 . Cesarean section can avoid or reduce the hypoxia of the fetus at birth and reduce the occurrence of NEC. Our study found that gestational diabetes was an independent risk factor for NEC. Previous studies have shown conflicting results between the association of maternal diabetes and necrotising enterocolitis. Boghossian, Grandi, et al. 26,27 showed the increased risk of necrotising enterocolitis with maternal diabetes in preterm infants. Lu 23 reported that long-term exposure to hyperglycemia during pregnancy could affect the fetal intestinal blood supply, and would further lead to ischemic injury of intestinal mucosa, which induce NEC. However, some studies 28,29 suggested that maternal diabetes was not associated with the incidence of neonatal NEC. Sepsis is one of the principal diseases that threaten the life of preterm infants and affect the prognosis of preterm infant. The incidence of preterm infants sepsis varies greatly in different countries, with a maximum of 17% in developing countries and a minimum of 0.45% in developed countries 30 . The lower the gestational age and birth weight, the higher the incidence of neonatal sepsis 30 . Therapy against sepsis plays an important role in the treatment of EP infants. Due to different causes and pathogenesis, neonatal sepsis is divided into early-onset sepsis and late-onset sepsis based on timing of occurrence 31 . In our study, early-onset sepsis and late-onset sepsis were analyzed separately. With the increasing use of antenatal prophylactic antibiotics, the incidence of early-onset sepsis had decreased 32 . Although the antenatal prophylactic antibiotic use ratio in the natural birth group was higher, we found that the incidence of early-onset sepsis in the spontaneous labor group was higher than that in the cesarean birth group. Natural birth did not increase the incidence of late-onset sepsis. The logistic regression analysis indicated that natural birth was an independent risk factor for EOS. Neonates often develop EOS by receiving bacterial infection from the mother in utero, during labour, as the neonate passes through the birth canal, or rarely through transplacental route 33 . We found that the incidence of hypertensive disorders in the cesarean birth group was significantly higher than that in the natural birth group. The logistic regression analysis did not indicated that hypertensive disorders was an independent risk factor for EOS and NEC. This was probably because hypertensive disorder complicating pregnancy is a major reason to choose caesarean section in the case of extremely premature delivery. And we found no significant differences between natural birth group and caesarean birth group regarding secondary adverse outcomes including IVH ≥ 3/ PVL, ROP ≥ 3, hsPDA and Apgar score ≤ 3 at 1 min ( P༞0.05 ) . The decision of whether to deliver an extremely preterm infant vaginally or by caesarean section is a complex one, as the circumstances of these cases can be very heterogeneous. Although caesarean birth has been proposed as a strategy to decrease neonatal morbidity and mortality among extremely preterm infants, Fear of poor or uncertain outcomes in EP infant was important factor affecting the parental decision. In addition, the surgical trauma due to the poor formation of the lower uterine segment was also the important reference factor. The mode of delivery should be discussed individually with the woman and her partner. It is important to acknowledge and understand the risks as she makes the decision to select cesarean birth at this stage of pregnancy. Our study can provide related information for clinical decision-making. The limitation of this study is the small sample size. Cases that died immediately in the delivery room due to lack of active and effective resuscitation or weren’t transferred to neonatal intensive care units ( NICUs ) after resuscitation were not included in this study. Our study only focused on short-term outcomes at discharge and did not consider long-term outcomes. Conclusions Compared with the caesarean birth group, the natural birth group has significantly higher incidence rates of early-onset sepsis and necrotizing enterocolitis ( NEC ). No significant differences were found between natural birth group and caesarean birth group regarding the incidence of neonatal death, LOS, IVH ≥ 3 / PVL, ROP ≥ 3, hsPDA and Apgar score ≤ 3 at 1 min. The logistic regression analysis showed that natural birth was an independent risk factor for early-onset sepsis and NEC ( OR = 2.032 and 2.731 respectively, P༜0.05 ), and the gestational diabetes was an independent risk factor for NEC. Overall, this study indicated a significant trend toward improved neonatal outcome with caesarean birth delivery. Due to caesarean birth during this periviable period clearly increases maternal morbidity, An individualized approach discussing is required, especially when there is uncertain neonatal outcome due to extreme prematurity. Declarations Ethical Approval and consent to participate All experimental protocols were approved by the ethical committee of Yuying Children’s Hospital of Wenzhou Medical University. Consents were obtained from legal guardians of all subjects. Consent to Publication Not applicable. Data Availability statement The datasets used and analysed during the current study available from the corresponding author on reasonable request. Data is provided within the supplementary information files. Conflict of interest The authors declare no competing interests. Funding Not applicable. Author contribution Qianmeng Huang participated in the study design, conducted the data analysis, drafted the initial manuscript and approved the final manuscript as submitted. Rongyue Wang contributed to the study design, reviewed and revised the manuscript, and approved the final manuscript as submitted. Jie Wu conducted the data analysis, reviewed and revised the manuscript, and approved the final manuscript as submitted. All authors have accepted responsibility for the entire content of this manuscript and approved its submission. Author information 1 The Second Affiliated Hospital and Yuying Children’s Hospital of Wenzhou Medical University, Department of Obstetrics and Gynecology, Wenzhou, 325000, China. References Barsoom MJ, Feresu SA, Chen A. Heterogeneity of Preterm Birth Subtypes in Relation to Neonatal Death. Obstetrics & Gynecology 113 , 516-522, doi:10.1097/aog.0b013e3181b473fc (2009). 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Tables Table 1 Maternal and Prenatal characterictics Vaginal delivery （ N = 103 ） Cesarean delivery ( N = 63 ) χ2 / t P Maternal characterictics Maternal age 30.9 ± 5.9 31.7 ± 5.5 -0.975 0.960 Gestational diabetes 23（ 22.3% ） 16（ 25.4% ） 0.205 0.651 Hypertensive disorder complicating pregnancy 3（ 2.9% ） 25（ 39.7% ） 37.691 ＜0.001 Chorioamnionitis 79（ 76.7% ） 31（ 49.2% ） 13.217 ＜0.001 Prophylactic antibiotic administration 86（ 83.5% ） 31（ 49.2% ） 22.091 ＜0.001 Steroid administration 79（ 76.7% ） 50（ 79.4% ） 0.160 0.689 Magnesium sulfate administration 58（ 56.3% ） 38（ 60.3% ） 0.257 0.612 Prenatal characterictics Gestational age ( X ± S , weeks ) 26.6 ± 1.0 27.1 ± 0.8 -3.194 0.002 Birth weight ( X ± S , g ) 957 ± 175 925 ± 190 1.069 0.287 Data are shown in n ( % ) or X ± S . Table 2 Univariate analyses of infantile outcome Vaginal delivery （ N = 103 ） Cesarean delivery ( N = 63 ) χ2 P Main adverse outcomes 100（24.3%） 40（15.9%） 6.629 0.010 Death 14（13.6%） 7（11.1%） 0.218 0.641 EOS 40（38.8%） 15（23.8%） 3.983 0.046 LOS 23（22.3%） 12（19%） 0.253 0.615 NEC 23（22.3%） 6（9.5%） 4.446 0.035 Secondary adverse outcomes 50（12.1%） 28（11.1%） 0.334 0.564 Grade III-IV IVH / PVL 27（26.2%） 16（25.3%） 0.014 0.907 ROP ≥ 3 6（5.8%） 2（3.2%） 0.599 0.439 hsPDA 9（8.7%） 6（9.5%） 0.029 0.864 Apgar score ≤ 3 at 1 min 8（7.8%） 4（6.3%） 0.117 0.432 Data are shown in n ( % ). EOS, Early-onset sepsis; LOS, Late-onset sepsis; NEC, Necrotizing enterocolitis; IVH/PVL, Intraventricular hemorrhage / Periventricular leukomalacia; ROP, Retinopathy of prematurity; hsPDA, Hemodynamically significant ductus arteriosus. Table 3 logistic analysis of EOS B SE Wald χ2 P OR 95% CI Vaginal delivery 0.709 0.358 3.915 0.048 2.032 1.007~4.101 0.454 0.202 5.049 0.025 1.575 Table 4 logistic analysis of NEC B SE Wald χ2 P OR 95% CI Vaginal delivery 1.005 0.490 4.203 0.040 2.731 1.045~7.137 -2.251 0.429 27.514 ＜0.001 0.105 Gestational diabetes 1.056 0.434 5.926 0.015 2.876 1.229~6.732 -1.867 0.261 51.339 ＜0.001 0.155 Additional Declarations No competing interests reported. Supplementary Files rawdata.xlsx Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-3790520","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":264730940,"identity":"d81e3d84-483f-432b-a613-912ff8d4b5f9","order_by":0,"name":"Qianmeng Huang","email":"","orcid":"","institution":"Yuying Children’s Hospital of Wenzhou Medical University","correspondingAuthor":false,"prefix":"","firstName":"Qianmeng","middleName":"","lastName":"Huang","suffix":""},{"id":264730941,"identity":"02c84c15-aa74-4785-be11-dbd9ecd8c631","order_by":1,"name":"Jie Wu","email":"","orcid":"","institution":"Yuying Children’s Hospital of Wenzhou Medical University","correspondingAuthor":false,"prefix":"","firstName":"Jie","middleName":"","lastName":"Wu","suffix":""},{"id":264730942,"identity":"2a3a5c1e-8b58-4654-b028-acff768b93c1","order_by":2,"name":"Rongyue Wang","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA50lEQVRIiWNgGAWjYBAC+wYIzcPP3tj4IKGihrAWgwMQWkay53CzwYMzx4jXYmNwI71N8mELMxFajvcefs3bZsNjcOZgW0ViAxsDf3t3Al4t9j3n0qx529J4JI83tt1I3CHDIHHm7Aa8WuwkcsyMedsO8/ABbbmReIaNwUAiF78WY4iW/zwMNxLbChLbmAlrMZyRY/yYt+0AjwBQCwNRWgzOnDFjnHMumUey52CzRMKZYzwE/WJwvMf4w5syO3t+9vaHH39U1Mjxt/fi1wIEbFI8SDwenOqQAPPHH8QoGwWjYBSMgpELAIalT2ZuLJalAAAAAElFTkSuQmCC","orcid":"","institution":"Yuying Children’s Hospital of Wenzhou Medical University","correspondingAuthor":true,"prefix":"","firstName":"Rongyue","middleName":"","lastName":"Wang","suffix":""}],"badges":[],"createdAt":"2023-12-22 07:14:20","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-3790520/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-3790520/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":56523408,"identity":"eb9479eb-cc46-4b0c-b287-03ba9d69bdc6","added_by":"auto","created_at":"2024-05-15 09:22:33","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":411185,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-3790520/v1/7c48ad7f-d9c0-43b7-a79b-13dce78e1770.pdf"},{"id":49122844,"identity":"59567a2c-8e62-494e-81ef-d884c186ef9c","added_by":"auto","created_at":"2024-01-03 13:39:01","extension":"xlsx","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":58128,"visible":true,"origin":"","legend":"","description":"","filename":"rawdata.xlsx","url":"https://assets-eu.researchsquare.com/files/rs-3790520/v1/bbc5dbc8dedd50e437428822.xlsx"}],"financialInterests":"No competing interests reported.","formattedTitle":"Influence of the delivery mode on the short-term outcomes of extremely preterm infants","fulltext":[{"header":"Introduction","content":"\u003cp\u003eExtremely preterm birth ( EPI ), defined as birth before 28 weeks of gestation, is 5% in preterm birth\u003csup\u003e1,2\u003c/sup\u003e. With extensive use of assisted reproduction technologies, increased high risk pregnancies and development of premature infants treatment, the EPI is rising in recent years\u003csup\u003e3\u003c/sup\u003e. Preterm birth is a major cause of perinatal and neonatal mortality as well as of short-and long-term morbidity in addition to birth defects. Due to prematurity, they suffer higher incidence rate in necrotizing enterocolitis, intraventricular hemorrhage, retinopathy of prematurity, infection and so on\u003csup\u003e4,5\u003c/sup\u003e. It is well known that the infants born at the lowest gestational ages have the worst outcome. The infants\u0026rsquo; immaturity has been hypothesized to be the primary reason for this. As survival increases at earlier gestational ages, the best mode of delivery is of increasing importance. The optimal delivery mode of EPI is a debatable point. Some studies \u003csup\u003e6\u0026ndash;8\u003c/sup\u003e showed that caesarean section was associated with a significant reduction of the perinatal mortality and morbidity of premature infants. However, other scholars\u003csup\u003e9,10\u003c/sup\u003e did not find a difference in neonatal morbidity or mortality between two groups. As the number of cases tends to be small, reports about the influence of the delivery mode on the outcomes of extremely preterm infants are relatively rare at present. The purpose of this study was to examine whether mode of delivery is associated with perinatal mortality and morbidity of extremely premature infants, and to help clinical treatment decision-making process.\u003c/p\u003e"},{"header":"Material and methods","content":"\u003cp\u003e1.\u0026nbsp; \u0026nbsp;Study population\u003c/p\u003e\n\u003cp\u003eThis study included 166 EPI born between 1 January 2018 and 31 December 2022 in the Second Affiliated Hospital of Wenzhou Medical University. Consents were obtained from legal guardians of all subjects. Inclusive criteria: (1).\u0026nbsp;Transferred to neonatal intensive care units ( NICUs ) after birth; (2). Born at\u0026nbsp;24-28 weeks\u0026rsquo; gestation; (3). singleton. Exclusion criteria: (1). Gave up treatment because of personal reasons; (2). Suffered from Serious congenital illnesses, such as complex congenital heart disease, chromosome abnormality, etc; (3). Twins or multiples. According to the delivery mode, they were divided into two groups: natural birth group and caesarean birth group. Ethics approval was obtained from hospital ethics committees, as required by national legislation.\u003c/p\u003e\n\u003cp\u003e2.\u0026nbsp;Data colletion\u003c/p\u003e\n\u003cp\u003e(1) Maternal age; Gestational diabetes; Hypertensive disorder complicating pregnancy; Chorioamnionitis; Prenatal interventions [ Steroid administration ( pregnant women received adequate treatment of dexamethasone before delivering ) , Prophylactic antibiotic administration ( pregnant women received antibiotic therapy before delivering, and the interval between the treatment and delivery was 4 hours or longer ) , Magnesium sulfate administration ] . (2)\u0026nbsp;Delivery mode; Gestational week; Birth weight; Apgar score \u0026le;3 at 1 min; Early-onset sepsis ( EOS ) ; Late-onset sepsis ( LOS ) ; Intraventricular hemorrhage ( IVH ) ; periventricular leukomalacia ( PVL ) ; retinopathy of prematurity ( ROP ) ; necrotizing enterocolitis ( NEC ) ; hemodynamically significant ductus arteriosus ( hsPDA ) ; Neonatal death ( neonatal died in the hospital or died in the short time after treatment abandonment ) .\u003c/p\u003e\n\u003cp\u003e3. Perinatal outcomes\u003c/p\u003e\n\u003cp\u003eMain\u0026nbsp;adverse outcomes: Neonatal death; Early-onset sepsis, Late-onset sepsis, EOS occured within 7days, as opposed to LOS, which was beyond 7days; NEC \u0026ge; 3, The criteria utilized in our survey for the diagnosis of NEC and for grading the severity of disease were based on Bell\u0026rsquo;s stage\u003csup\u003e11\u003c/sup\u003e. Secondary adverse outcomes: Intraventricular hemorrhage grade 3 or higher ( IVH \u0026ge; 3) , graded according to Papile et al\u003csup\u003e12\u003c/sup\u003e; Periventricular leukomalacia, defined according to de Vries et al\u003csup\u003e13\u003c/sup\u003e; Retinopathy of prematurity stage 3 or higher ( ROP \u0026ge; 3 ) , defined according to the International Classification of Retinopathy of Prematurity\u003csup\u003e14\u003c/sup\u003e; hsPDA; Apgar score \u0026le;3 at 1 min.\u003c/p\u003e\n\u003cp\u003e4. Statistical analysis\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eAll statistical analyses were performed using SPSS 20.0. Continuous variables were shown as means \u0026plusmn; standard deviation ( SD ) , which were analyzed using \u003cem\u003et\u003c/em\u003e-tests. Categorical variables were presented as rates and odds ratio with 95% confidence intervals ( CI ) , which were analyzed using Chi-square tests. Logistic regression were used to analyze the risk factors of survival in preterm infants. A \u003cem\u003ep\u003c/em\u003e-value \u0026lt; 0.05 was considered statistically significant.\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003e1.\u0026nbsp; \u0026nbsp;Demographics of EPI and mothers\u003c/p\u003e\n\u003cp\u003eDuring the 5-year study, in total, 166 EP infants were enrolled. According to the delivery mode, they were divided into two groups: natural birth group ( \u003cem\u003eN\u003c/em\u003e=103 ) and caesarean birth group ( \u003cem\u003eN\u003c/em\u003e = 63 ) . The incidence of chorioamnionitis and prophylactic antibiotic\u0026nbsp;exposure prior to delivery in\u0026nbsp;natural birth group\u0026nbsp;were higher than that in\u0026nbsp;caesarean birth group ( \u003cem\u003eP\u003c/em\u003e＜0.05 ) . The\u0026nbsp;hypertensive disorder\u0026nbsp;occurring rate and gestational age were significantly lower in\u0026nbsp;natural birth group\u0026nbsp;than in\u0026nbsp;caesarean birth group ( \u003cem\u003eP\u003c/em\u003e＜0.05 ) . All other baseline characteristics including maternal age at delivery, incidence of\u0026nbsp;gestational diabetes,\u0026nbsp;glucocorticoid\u0026nbsp;and magnesium sulfate exposure prior to delivery and birth weight were not significantly different between the two groups\u0026nbsp;( \u003cem\u003eP\u003c/em\u003e＞0.05 ) . The maternal and renatal characterictics are shown in table1.\u003c/p\u003e\n\u003cp\u003e2. Adverse outcomes of EP infants\u003c/p\u003e\n\u003cp\u003eThe incidence of neonatal death, early-onset sepsis, late-onset sepsis, NEC, IVH \u0026ge; 3/ PVL, ROP \u0026ge; 3,\u0026nbsp;hsPDA, Apgar score \u0026le; 3 at 1 min was repectively 12.7% ( 21 of 166 ) , \u0026nbsp;33.1 % ( 55 of 166 ) , 21.1% ( 35 of 166 ) , 17.5% ( 29 of 166 ) , 25.9% ( 43 of 166 ) , 4.8% ( 8 of 166 ) , 9% ( 15 of 166 ) , 7.2% ( 12 of 166 ) . In the natural birth group, there was an increased risk for main adverse outcomes, early-onset sepsis and NEC ( \u003cem\u003eP\u003c/em\u003e＜0.05 ) . There were no significant difference in incidence of neonatal death and late-onset sepsis between two groups ( \u003cem\u003eP\u003c/em\u003e＞0.05 ) . No significant differences were found between natural birth group and caesarean birth group regarding secondary adverse outcomes including IVH \u0026ge; 3 / PVL, ROP \u0026ge; 3, hsPDA and Apgar score \u0026le; 3 at 1 min ( \u003cem\u003eP\u003c/em\u003e＞0.05 ) . The adverse outcomes of EP infants are shown in table 2.\u003c/p\u003e\n\u003cp\u003e3. Logistic regression analysis of risk factors for adverse outcomes\u003c/p\u003e\n\u003cp\u003eWe made logistic regression analysis by taking EOS and NEC as dependent variable and taking delivery mode, gestational diabetes, hypertensive disorder, Chorioamnionitis, glucocorticoid, prophylactic antibiotic\u0026nbsp;and magnesium sulfate exposure prior to delivery as independent variable. The logistic regression analysis indicated that natural birth was an independent risk factor for early-onset sepsis and NEC (\u003cem\u003e\u0026nbsp;OR\u003c/em\u003e = 2.032 and 2.731 respectively，\u003cem\u003eP\u003c/em\u003e＜0.05 ) ( Table 3 and Table 4 ) , and the gestational diabetes was an independent risk factor for NEC ( \u003cem\u003eOR\u0026nbsp;\u003c/em\u003e= 2.876，\u003cem\u003eP\u003c/em\u003e＜0.05 ) ( Table 4 ) .\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eWith economic growth, social progress and improvements in medicine, the preterm birth has become an important issue. We need to make more efforts to decrease mortality and improve short-term and long-term prognosis of extremely premature infants. There are many reasons to choose caesarean section in the case of extremely premature delivery, including maternal complications, fetal distress, placenta abruption, fetal malposition and so on. EP infants are at higher risk of morbidity and mortality owing to extreme immaturity\u003csup\u003e15,16\u003c/sup\u003e. Whether caesarean birth will reduce the risk of morbidity and mortality approaches the focus of attention more and more.\u003c/p\u003e \u003cp\u003eNEC is common digestive emergency in EP infants which may cause gastrointestinal perforation, prolong hospitalization time and increase the risk of neonatal death\u003csup\u003e17\u0026ndash;19\u003c/sup\u003e. Yee, Ris, et al.\u003csup\u003e20,21\u003c/sup\u003e reported that caesarean birth had no significant effect on NEC. While others\u003csup\u003e22\u0026ndash;24\u003c/sup\u003e reported that caesarean birth was associated with decreased risk of NEC. Luig, et al.\u003csup\u003e25\u003c/sup\u003e reported that caesarean birth did not significantly affect the risk of NEC in preterm infants born between 24 and 27 weeks GA, but was associated with a significantly increased risk in those born between 28 and 31 weeks GA. In our study, the natural birth group had significantly higher incidence rates of necrotizing enterocolitis( 22.3% vs 9.5% ). The logistic regression analysis indicated that natural birth was an independent risk factor for NEC. When the fetus is in hypoxic distress, the blood in the body will be redistributed, and the blood vessels such as intestinal mucosa will contract strongly, so that more blood will be supplied to important organs such as the heart and brain, which will then lead to a sharp decline in the blood supply of the gastrointestinal tract, ischemia injury of the intestinal mucosa, and induce NEC\u003csup\u003e23\u003c/sup\u003e. Cesarean section can avoid or reduce the hypoxia of the fetus at birth and reduce the occurrence of NEC.\u003c/p\u003e \u003cp\u003eOur study found that gestational diabetes was an independent risk factor for NEC. Previous studies have shown conflicting results between the association of maternal diabetes and necrotising enterocolitis. Boghossian, Grandi, et al.\u003csup\u003e26,27\u003c/sup\u003e showed the increased risk of necrotising enterocolitis with maternal diabetes in preterm infants. Lu\u003csup\u003e23\u003c/sup\u003e reported that long-term exposure to hyperglycemia during pregnancy could affect the fetal intestinal blood supply, and would further lead to ischemic injury of intestinal mucosa, which induce NEC. However, some studies\u003csup\u003e28,29\u003c/sup\u003e suggested that maternal diabetes was not associated with the incidence of neonatal NEC.\u003c/p\u003e \u003cp\u003eSepsis is one of the principal diseases that threaten the life of preterm infants and affect the prognosis of preterm infant. The incidence of preterm infants sepsis varies greatly in different countries, with a maximum of 17% in developing countries and a minimum of 0.45% in developed countries\u003csup\u003e30\u003c/sup\u003e. The lower the gestational age and birth weight, the higher the incidence of neonatal sepsis\u003csup\u003e30\u003c/sup\u003e. Therapy against sepsis plays an important role in the treatment of EP infants. Due to different causes and pathogenesis, neonatal sepsis is divided into early-onset sepsis and late-onset sepsis based on timing of occurrence\u003csup\u003e31\u003c/sup\u003e. In our study, early-onset sepsis and late-onset sepsis were analyzed separately. With the increasing use of antenatal prophylactic antibiotics, the incidence of early-onset sepsis had decreased\u003csup\u003e32\u003c/sup\u003e. Although the antenatal prophylactic antibiotic use ratio in the natural birth group was higher, we found that the incidence of early-onset sepsis in the spontaneous labor group was higher than that in the cesarean birth group. Natural birth did not increase the incidence of late-onset sepsis. The logistic regression analysis indicated that natural birth was an independent risk factor for EOS. Neonates often develop EOS by receiving bacterial infection from the mother in utero, during labour, as the neonate passes through the birth canal, or rarely through transplacental route\u003csup\u003e33\u003c/sup\u003e.\u003c/p\u003e \u003cp\u003eWe found that the incidence of hypertensive disorders in the cesarean birth group was significantly higher than that in the natural birth group. The logistic regression analysis did not indicated that hypertensive disorders was an independent risk factor for EOS and NEC. This was probably because hypertensive disorder complicating pregnancy is a major reason to choose caesarean section in the case of extremely premature delivery. And we found no significant differences between natural birth group and caesarean birth group regarding secondary adverse outcomes including IVH\u0026thinsp;\u0026ge;\u0026thinsp;3/ PVL, ROP\u0026thinsp;\u0026ge;\u0026thinsp;3, hsPDA and Apgar score\u0026thinsp;\u0026le;\u0026thinsp;3 at 1 min ( P༞0.05 ) .\u003c/p\u003e \u003cp\u003eThe decision of whether to deliver an extremely preterm infant vaginally or by caesarean section is a complex one, as the circumstances of these cases can be very heterogeneous. Although caesarean birth has been proposed as a strategy to decrease neonatal morbidity and mortality among extremely preterm infants, Fear of poor or uncertain outcomes in EP infant was important factor affecting the parental decision. In addition, the surgical trauma due to the poor formation of the lower uterine segment was also the important reference factor. The mode of delivery should be discussed individually with the woman and her partner. It is important to acknowledge and understand the risks as she makes the decision to select cesarean birth at this stage of pregnancy. Our study can provide related information for clinical decision-making.\u003c/p\u003e \u003cp\u003eThe limitation of this study is the small sample size. Cases that died immediately in the delivery room due to lack of active and effective resuscitation or weren\u0026rsquo;t transferred to neonatal intensive care units ( NICUs ) after resuscitation were not included in this study. Our study only focused on short-term outcomes at discharge and did not consider long-term outcomes.\u003c/p\u003e"},{"header":"Conclusions","content":"\u003cp\u003eCompared with the caesarean birth group, the natural birth group has significantly higher incidence rates of early-onset sepsis and necrotizing enterocolitis ( NEC ). No significant differences were found between natural birth group and caesarean birth group regarding the incidence of neonatal death, LOS, IVH\u0026thinsp;\u0026ge;\u0026thinsp;3 / PVL, ROP\u0026thinsp;\u0026ge;\u0026thinsp;3, hsPDA and Apgar score\u0026thinsp;\u0026le;\u0026thinsp;3 at 1 min. The logistic regression analysis showed that natural birth was an independent risk factor for early-onset sepsis and NEC ( OR\u0026thinsp;=\u0026thinsp;2.032 and 2.731 respectively, P༜0.05 ), and the gestational diabetes was an independent risk factor for NEC. Overall, this study indicated a significant trend toward improved neonatal outcome with caesarean birth delivery. Due to caesarean birth during this periviable period clearly increases maternal morbidity, An individualized approach discussing is required, especially when there is uncertain neonatal outcome due to extreme prematurity.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003eEthical Approval and consent to participate\u003c/p\u003e\n\u003cp\u003eAll experimental protocols were approved by the ethical committee of Yuying Children’s Hospital of Wenzhou Medical University. Consents were obtained from legal guardians of all subjects.\u003c/p\u003e\n\u003cp\u003eConsent to Publication\u003c/p\u003e\n\u003cp\u003eNot applicable.\u003c/p\u003e\n\u003cp\u003eData Availability statement\u003c/p\u003e\n\u003cp\u003eThe datasets used and analysed during the current study available from the corresponding author on reasonable request. Data is provided within the supplementary information files.\u003c/p\u003e\n\u003cp\u003eConflict of interest\u003c/p\u003e\n\u003cp\u003eThe authors declare no competing interests.\u003c/p\u003e\n\u003cp\u003eFunding\u003c/p\u003e\n\u003cp\u003eNot applicable.\u003c/p\u003e\n\u003cp\u003eAuthor contribution \u0026nbsp;\u003c/p\u003e\n\u003cp\u003eQianmeng Huang participated in the study design, conducted the data analysis, drafted the initial manuscript and approved the final manuscript as submitted. Rongyue Wang contributed to the study design, reviewed and revised the manuscript, and approved the final manuscript as submitted. Jie Wu conducted the data analysis, reviewed and revised the manuscript, and approved the final manuscript as submitted. All authors have accepted responsibility for the entire content of this manuscript and approved its submission.\u003c/p\u003e\n\u003cp\u003eAuthor information\u003c/p\u003e\n\u003cp\u003e\u003csup\u003e1\u003c/sup\u003eThe Second Affiliated Hospital and Yuying Children’s Hospital of Wenzhou Medical University, Department of Obstetrics and Gynecology, Wenzhou, 325000, China.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eBarsoom MJ, Feresu SA, Chen A. Heterogeneity of Preterm Birth Subtypes in Relation to Neonatal Death. \u003cem\u003eObstetrics \u0026amp; Gynecology\u003c/em\u003e \u003cstrong\u003e113\u003c/strong\u003e, 516-522, doi:10.1097/aog.0b013e3181b473fc (2009).\u003c/li\u003e\n\u003cli\u003ePreterm Birth (2016) World Health Organization. \u003cem\u003ehttps ://\u003c/em\u003ewww.who.int/en/news-room/fact-sheets/detail/preterm-birth\u003cem\u003e.\u003c/em\u003e\u003c/li\u003e\n\u003cli\u003eWorld Health Organization. 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Incidence and evolution of subependymal and intraventricular hemorrhage: a study of infants with birth weights less than 1,500 gm. \u003cem\u003eJournal of Pediatrics\u003c/em\u003e \u003cstrong\u003e92\u003c/strong\u003e, 529-534, doi:10.1016/S0022-3476(78)80282-0 (1978).\u003c/li\u003e\n\u003cli\u003ede Vries LS, Eken P, Dubowitz LM. The spectrum of leukomalacia using cranial ultrasound. \u003cem\u003eBehav Brain Res.\u003c/em\u003e \u003cstrong\u003e49\u003c/strong\u003e, 1-6, doi:10.1016/s0166-4328(05)80189-5 (1992).\u003c/li\u003e\n\u003cli\u003eInternational Committee for the Classification of Retinopathy of P. The International Classification of Retinopathy of Prematurity revisited. \u003cem\u003eArch Ophthalmol\u003c/em\u003e \u003cstrong\u003e123\u003c/strong\u003e, 991-999 (2005).\u003c/li\u003e\n\u003cli\u003eHowson CP, Kinney MV, McDougall L, et al. Born too soon: preterm birth matters. \u003cem\u003eReprod Health.\u003c/em\u003e \u003cstrong\u003e10 Suppl 1\u003c/strong\u003e, s1, doi:10.1186/1742-4755-10-S1-S1 (2013).\u003c/li\u003e\n\u003cli\u003eButler AS, Behrman RE. Preterm Birth: Causes, Consequences, and Prevention. \u003cem\u003eNational Academies Press, Washington\u003c/em\u003e, doi:10.17226/11622 (2007).\u003c/li\u003e\n\u003cli\u003eLin PW, Stoll BJ. Necrotising enterocolitis. \u003cem\u003eLancet\u003c/em\u003e \u003cstrong\u003e368\u003c/strong\u003e, 1271-1283 (2006).\u003c/li\u003e\n\u003cli\u003eThompson AM, Bizzarro MJ. Necrotizing enterocolitisin newborns: pathogenesis, prevention and management. \u003cem\u003eDrugs.\u003c/em\u003e \u003cstrong\u003e68\u003c/strong\u003e, 1227-1238, doi:10.1111/j.1558-5646.2007.00009.x (2008).\u003c/li\u003e\n\u003cli\u003eSchulzke SM, Deshpande GC, Patole SK. Neurodevelopmental outcomes of very low-birth-weight infants with necrotizing enterocolitis: a systematic review of observational studies. . \u003cem\u003eArchives of pediatrics \u0026amp; adolescent medicine\u003c/em\u003e \u003cstrong\u003e161\u003c/strong\u003e, 583-590, doi:10.1001/archpedi.161.6.583 (2007).\u003c/li\u003e\n\u003cli\u003eYee WH, Soraisham AS, Shah VS, et al. Incidence and timing of presentation of necrotizing enterocolitis in preterm infants. \u003cem\u003ePediatrics.\u003c/em\u003e \u003cstrong\u003e129\u003c/strong\u003e, e298-304, doi:10.1542/peds.2011-2022 (2012).\u003c/li\u003e\n\u003cli\u003eRiskin A, Riskin-Mashiah S, Itzchaki O, et al. Mode of delivery and necrotizing enterocolitis in very preterm very-low-birth-weight infants. \u003cem\u003eJ Matern Fetal Neonatal Med.\u003c/em\u003e \u003cstrong\u003e34\u003c/strong\u003e, 3933-3939, doi:10.1080/14767058.2019.1702947 (2021).\u003c/li\u003e\n\u003cli\u003eGuthrie SO, Gordon PV, Thomas V, et al. Necrotizing enterocolitis among neonates in the United States. \u003cem\u003eJ Perinatol.\u003c/em\u003e \u003cstrong\u003e23\u003c/strong\u003e, 278-285, doi:10.1038/sj.jp.7210892 (2003).\u003c/li\u003e\n\u003cli\u003eLu CY, Liu KF, Qiao GX, et al. Risk factors for necrotizing enterocolitis in preterm infants: a Meta analysis. \u003cem\u003eZhongguo Dang Dai Er Ke Za Zhi.\u003c/em\u003e \u003cstrong\u003e24\u003c/strong\u003e, 908-916, doi:10.7499/j.issn.1008-8830.2202085 (2022).\u003c/li\u003e\n\u003cli\u003eUauy RD, Fanaroff AA, Korones SB, et al. Necrotizing enterocolitis in very low birth weight infants: Biodemographic and clinical correlates. \u003cem\u003eJournal of Pediatrics\u003c/em\u003e \u003cstrong\u003e119\u003c/strong\u003e, 630-638, doi:10.1016/S0022-3476(05)82418-7 (1991).\u003c/li\u003e\n\u003cli\u003eLuig M, Lui K. Epidemiology of necrotizing enterocolitis--Part II: Risks and susceptibility of premature infants during the surfactant era: a regional study. \u003cem\u003eJ Paediatr Child Health.\u003c/em\u003e \u003cstrong\u003e41\u003c/strong\u003e, 174-179, doi:10.1111/j.1440-1754.2005.00583.x (2005).\u003c/li\u003e\n\u003cli\u003eBoghossian NS, Hansen NI, Bell EF, et al. Outcomes of Extremely Preterm Infants Born to Insulin-Dependent Diabetic Mothers. \u003cem\u003ePEDIATRICS\u003c/em\u003e \u003cstrong\u003e137\u003c/strong\u003e, e20153424., doi:10.1542/peds.2015-3424 (2016).\u003c/li\u003e\n\u003cli\u003eGrandi C, Tapia JL, Cardoso VC. Impact of maternal diabetes mellitus on mortality and morbidity of very low birth weight infants: a multicenter Latin America study. \u003cem\u003eJ Pediatr (Rio J).\u003c/em\u003e \u003cstrong\u003e91\u003c/strong\u003e, 234-241, doi:10.1016/j.jped.2014.08.007 (2014).\u003c/li\u003e\n\u003cli\u003eRazak A, Faden M. Association of maternal diabetes mellitus with preterm infant outcomes: a systematic review and meta-analysis. \u003cem\u003eArchives of disease in childhood. Fetal and neonatal edition.\u003c/em\u003e \u003cstrong\u003e106\u003c/strong\u003e, 271-277, doi:10.1136/archdischild-2020-320054 (2021).\u003c/li\u003e\n\u003cli\u003eHitaka D, Morisaki N, Miyazono Y, et al. Neonatal outcomes of very low birthweight infants born to mothers with hyperglycaemia in pregnancy: a retrospective cohort study in Japan. \u003cem\u003eBMJ Paediatr Open.\u003c/em\u003e \u003cstrong\u003e3\u003c/strong\u003e, e000491., doi:10.1136/bmjpo-2019-000491 (2019).\u003c/li\u003e\n\u003cli\u003eFlerschmann-Struzek C, Goldfarb DM, Schlattmann P, et al.The global burden of paediatric and neonatal sepsis: a systematic review. \u003cem\u003eThe lancet. Respiratory medicine.\u003c/em\u003e \u003cstrong\u003e6\u003c/strong\u003e, 223-230, doi:10.1016/S2213-2600(18)30063-8 (2018).\u003c/li\u003e\n\u003cli\u003eDuggan HL, Chow SSW, Austin NC , et al. Early-onset sepsis in very preterm neonates in Australia and New Zealand, 2007-2018. \u003cem\u003eArch Dis Child Fetal Neonatal Ed.\u003c/em\u003e \u003cstrong\u003e108\u003c/strong\u003e, 31-37, doi:10.1136/archdischild-2021-323243 (2023).\u003c/li\u003e\n\u003cli\u003ePuopolo KM, Benitz WE, Zaoutis TE. Management of Neonates Born at \u0026le;34 6/7 Weeks\u0026apos; Gestation With Suspected or Proven Early-Onset Bacterial Sepsis. \u003cem\u003ePediatrics.\u003c/em\u003e \u003cstrong\u003e142\u003c/strong\u003e, e20182896, doi:10.1542/peds.2018-2896 (2018).\u003c/li\u003e\n\u003cli\u003eSimonsen KA, Anderson-Berry AL, Delair SF. Early-Onset neonatal sepsis. \u003cem\u003eClin Microbiol Rev\u003c/em\u003e \u003cstrong\u003e27\u003c/strong\u003e, 21-47 (2014).\u003c/li\u003e\n\u003c/ol\u003e"},{"header":"Tables","content":"\u003cp\u003eTable 1 Maternal and Prenatal characterictics\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd width=\"29.783393501805055%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.981949458483754%\" valign=\"top\"\u003e\n \u003cp\u003eVaginal delivery\u003c/p\u003e\n \u003cp\u003e（\u0026nbsp;\u003cem\u003eN\u003c/em\u003e = 103\u0026nbsp;）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.855595667870038%\" valign=\"top\"\u003e\n \u003cp\u003eCesarean delivery\u003c/p\u003e\n \u003cp\u003e(\u003cem\u003e\u0026nbsp;N\u003c/em\u003e = 63 )\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.870036101083034%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cem\u003e\u0026chi;2\u003c/em\u003e/\u003cem\u003et\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.509025270758123%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"29.783393501805055%\" valign=\"top\"\u003e\n \u003cp\u003eMaternal characterictics\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.981949458483754%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.855595667870038%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.870036101083034%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.509025270758123%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"29.783393501805055%\" valign=\"top\"\u003e\n \u003cp\u003eMaternal age\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.981949458483754%\" valign=\"top\"\u003e\n \u003cp\u003e30.9 \u0026plusmn; 5.9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.855595667870038%\" valign=\"top\"\u003e\n \u003cp\u003e31.7 \u0026plusmn; 5.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.870036101083034%\" valign=\"top\"\u003e\n \u003cp\u003e-0.975\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.509025270758123%\" valign=\"top\"\u003e\n \u003cp\u003e0.960\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"29.783393501805055%\" valign=\"top\"\u003e\n \u003cp\u003eGestational diabetes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.981949458483754%\" valign=\"top\"\u003e\n \u003cp\u003e23（\u0026nbsp;22.3%\u0026nbsp;）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.855595667870038%\" valign=\"top\"\u003e\n \u003cp\u003e16（\u0026nbsp;25.4%\u0026nbsp;）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.870036101083034%\" valign=\"top\"\u003e\n \u003cp\u003e0.205\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.509025270758123%\" valign=\"top\"\u003e\n \u003cp\u003e0.651\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"29.783393501805055%\" valign=\"top\"\u003e\n \u003cp\u003eHypertensive disorder complicating pregnancy\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.981949458483754%\" valign=\"top\"\u003e\n \u003cp\u003e3（\u0026nbsp;2.9%\u0026nbsp;）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.855595667870038%\" valign=\"top\"\u003e\n \u003cp\u003e25（\u0026nbsp;39.7%\u0026nbsp;）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.870036101083034%\" valign=\"top\"\u003e\n \u003cp\u003e37.691\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.509025270758123%\" valign=\"top\"\u003e\n \u003cp\u003e＜0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"29.783393501805055%\" valign=\"top\"\u003e\n \u003cp\u003eChorioamnionitis\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.981949458483754%\" valign=\"top\"\u003e\n \u003cp\u003e79（\u0026nbsp;76.7%\u0026nbsp;）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.855595667870038%\" valign=\"top\"\u003e\n \u003cp\u003e31（\u0026nbsp;49.2%\u0026nbsp;）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.870036101083034%\" valign=\"top\"\u003e\n \u003cp\u003e13.217\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.509025270758123%\" valign=\"top\"\u003e\n \u003cp\u003e＜0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"29.783393501805055%\" valign=\"top\"\u003e\n \u003cp\u003eProphylactic antibiotic administration\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.981949458483754%\" valign=\"top\"\u003e\n \u003cp\u003e86（\u0026nbsp;83.5%\u0026nbsp;）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.855595667870038%\" valign=\"top\"\u003e\n \u003cp\u003e31（\u0026nbsp;49.2%\u0026nbsp;）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.870036101083034%\" valign=\"top\"\u003e\n \u003cp\u003e22.091\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.509025270758123%\" valign=\"top\"\u003e\n \u003cp\u003e＜0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"29.783393501805055%\" valign=\"top\"\u003e\n \u003cp\u003eSteroid administration\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.981949458483754%\" valign=\"top\"\u003e\n \u003cp\u003e79（\u0026nbsp;76.7%\u0026nbsp;）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.855595667870038%\" valign=\"top\"\u003e\n \u003cp\u003e50（\u0026nbsp;79.4%\u0026nbsp;）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.870036101083034%\" valign=\"top\"\u003e\n \u003cp\u003e0.160\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.509025270758123%\" valign=\"top\"\u003e\n \u003cp\u003e0.689\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"29.783393501805055%\" valign=\"top\"\u003e\n \u003cp\u003eMagnesium sulfate administration\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.981949458483754%\" valign=\"top\"\u003e\n \u003cp\u003e58（\u0026nbsp;56.3%\u0026nbsp;）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.855595667870038%\" valign=\"top\"\u003e\n \u003cp\u003e38（\u0026nbsp;60.3%\u0026nbsp;）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.870036101083034%\" valign=\"top\"\u003e\n \u003cp\u003e0.257\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.509025270758123%\" valign=\"top\"\u003e\n \u003cp\u003e0.612\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"29.783393501805055%\" valign=\"top\"\u003e\n \u003cp\u003ePrenatal characterictics\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.981949458483754%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.855595667870038%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.870036101083034%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.509025270758123%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"29.783393501805055%\" valign=\"top\"\u003e\n \u003cp\u003eGestational age ( \u003cem\u003eX \u0026plusmn; S\u003c/em\u003e, weeks )\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.981949458483754%\" valign=\"top\"\u003e\n \u003cp\u003e26.6 \u0026plusmn; 1.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.855595667870038%\" valign=\"top\"\u003e\n \u003cp\u003e27.1 \u0026plusmn; 0.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.870036101083034%\" valign=\"top\"\u003e\n \u003cp\u003e-3.194\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.509025270758123%\" valign=\"top\"\u003e\n \u003cp\u003e0.002\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"29.783393501805055%\" valign=\"top\"\u003e\n \u003cp\u003eBirth weight ( \u003cem\u003eX \u0026plusmn; S\u003c/em\u003e, g )\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.981949458483754%\" valign=\"top\"\u003e\n \u003cp\u003e957 \u0026plusmn; 175\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.855595667870038%\" valign=\"top\"\u003e\n \u003cp\u003e925 \u0026plusmn; 190\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.870036101083034%\" valign=\"top\"\u003e\n \u003cp\u003e1.069\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.509025270758123%\" valign=\"top\"\u003e\n \u003cp\u003e0.287\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eData are shown in \u003cem\u003en\u003c/em\u003e ( % ) or \u003cem\u003eX \u0026plusmn; S\u003c/em\u003e.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eTable 2 Univariate analyses of infantile outcome\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd width=\"23.869801084990957%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.146473779385172%\" valign=\"top\"\u003e\n \u003cp\u003eVaginal delivery\u003c/p\u003e\n \u003cp\u003e（\u0026nbsp;\u003cem\u003eN\u003c/em\u003e = 103\u0026nbsp;）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.24231464737794%\" valign=\"top\"\u003e\n \u003cp\u003eCesarean delivery\u003c/p\u003e\n \u003cp\u003e( \u003cem\u003eN\u003c/em\u003e = 63 )\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.019891500904158%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cem\u003e\u0026chi;2\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.72151898734177%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"23.869801084990957%\" valign=\"top\"\u003e\n \u003cp\u003eMain\u0026nbsp;adverse outcomes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.146473779385172%\" valign=\"top\"\u003e\n \u003cp\u003e100（24.3%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.24231464737794%\" valign=\"top\"\u003e\n \u003cp\u003e40（15.9%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.019891500904158%\" valign=\"top\"\u003e\n \u003cp\u003e6.629\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.72151898734177%\" valign=\"top\"\u003e\n \u003cp\u003e0.010\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"23.869801084990957%\" valign=\"top\"\u003e\n \u003cp\u003eDeath\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.146473779385172%\" valign=\"top\"\u003e\n \u003cp\u003e14（13.6%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.24231464737794%\" valign=\"top\"\u003e\n \u003cp\u003e7（11.1%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.019891500904158%\" valign=\"top\"\u003e\n \u003cp\u003e0.218\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.72151898734177%\" valign=\"top\"\u003e\n \u003cp\u003e0.641\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"23.869801084990957%\" valign=\"top\"\u003e\n \u003cp\u003eEOS\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.146473779385172%\" valign=\"top\"\u003e\n \u003cp\u003e40（38.8%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.24231464737794%\" valign=\"top\"\u003e\n \u003cp\u003e15（23.8%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.019891500904158%\" valign=\"top\"\u003e\n \u003cp\u003e3.983\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.72151898734177%\" valign=\"top\"\u003e\n \u003cp\u003e0.046\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"23.869801084990957%\" valign=\"top\"\u003e\n \u003cp\u003eLOS\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.146473779385172%\" valign=\"top\"\u003e\n \u003cp\u003e23（22.3%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.24231464737794%\" valign=\"top\"\u003e\n \u003cp\u003e12（19%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.019891500904158%\" valign=\"top\"\u003e\n \u003cp\u003e0.253\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.72151898734177%\" valign=\"top\"\u003e\n \u003cp\u003e0.615\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"23.869801084990957%\" valign=\"top\"\u003e\n \u003cp\u003eNEC\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.146473779385172%\" valign=\"top\"\u003e\n \u003cp\u003e23（22.3%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.24231464737794%\" valign=\"top\"\u003e\n \u003cp\u003e6（9.5%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.019891500904158%\" valign=\"top\"\u003e\n \u003cp\u003e4.446\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.72151898734177%\" valign=\"top\"\u003e\n \u003cp\u003e0.035\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"23.869801084990957%\" valign=\"top\"\u003e\n \u003cp\u003eSecondary adverse outcomes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.146473779385172%\" valign=\"top\"\u003e\n \u003cp\u003e50（12.1%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.24231464737794%\" valign=\"top\"\u003e\n \u003cp\u003e28（11.1%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.019891500904158%\" valign=\"top\"\u003e\n \u003cp\u003e0.334\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.72151898734177%\" valign=\"top\"\u003e\n \u003cp\u003e0.564\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"23.869801084990957%\" valign=\"top\"\u003e\n \u003cp\u003eGrade III-IV IVH / PVL\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.146473779385172%\" valign=\"top\"\u003e\n \u003cp\u003e27（26.2%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.24231464737794%\" valign=\"top\"\u003e\n \u003cp\u003e16（25.3%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.019891500904158%\" valign=\"top\"\u003e\n \u003cp\u003e0.014\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.72151898734177%\" valign=\"top\"\u003e\n \u003cp\u003e0.907\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"23.869801084990957%\" valign=\"top\"\u003e\n \u003cp\u003eROP \u0026ge; 3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.146473779385172%\" valign=\"top\"\u003e\n \u003cp\u003e6（5.8%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.24231464737794%\" valign=\"top\"\u003e\n \u003cp\u003e2（3.2%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.019891500904158%\" valign=\"top\"\u003e\n \u003cp\u003e0.599\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.72151898734177%\" valign=\"top\"\u003e\n \u003cp\u003e0.439\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"23.869801084990957%\" valign=\"top\"\u003e\n \u003cp\u003ehsPDA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.146473779385172%\" valign=\"top\"\u003e\n \u003cp\u003e9（8.7%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.24231464737794%\" valign=\"top\"\u003e\n \u003cp\u003e6（9.5%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.019891500904158%\" valign=\"top\"\u003e\n \u003cp\u003e0.029\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.72151898734177%\" valign=\"top\"\u003e\n \u003cp\u003e0.864\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"23.869801084990957%\" valign=\"top\"\u003e\n \u003cp\u003eApgar score \u0026le; 3 at 1 min\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.146473779385172%\" valign=\"top\"\u003e\n \u003cp\u003e8（7.8%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.24231464737794%\" valign=\"top\"\u003e\n \u003cp\u003e4（6.3%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.019891500904158%\" valign=\"top\"\u003e\n \u003cp\u003e0.117\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.72151898734177%\" valign=\"top\"\u003e\n \u003cp\u003e0.432\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eData are shown in \u003cem\u003en\u003c/em\u003e ( % ).\u003c/p\u003e\n\u003cp\u003eEOS, Early-onset sepsis; LOS, Late-onset sepsis; NEC, Necrotizing enterocolitis; IVH/PVL, Intraventricular hemorrhage / Periventricular leukomalacia; ROP, Retinopathy of prematurity; hsPDA, Hemodynamically significant ductus arteriosus.\u003c/p\u003e\n\u003cp\u003eTable 3 logistic analysis of EOS\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd width=\"18.806509945750452%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.30741410488246%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cem\u003eB\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.211573236889693%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cem\u003eSE\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.743218806509946%\" valign=\"top\"\u003e\n \u003cp\u003eWald\u003cem\u003e\u0026chi;2\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.5623869801085%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.5623869801085%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cem\u003eOR\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"18.806509945750452%\" valign=\"top\"\u003e\n \u003cp\u003e95%\u003cem\u003eCI\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"18.806509945750452%\" valign=\"top\"\u003e\n \u003cp\u003eVaginal delivery\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.30741410488246%\" valign=\"top\"\u003e\n \u003cp\u003e0.709\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.211573236889693%\" valign=\"top\"\u003e\n \u003cp\u003e0.358\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.743218806509946%\" valign=\"top\"\u003e\n \u003cp\u003e3.915\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.5623869801085%\" valign=\"top\"\u003e\n \u003cp\u003e0.048\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.5623869801085%\" valign=\"top\"\u003e\n \u003cp\u003e2.032\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"18.806509945750452%\" valign=\"top\"\u003e\n \u003cp\u003e1.007~4.101\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"18.806509945750452%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.30741410488246%\" valign=\"top\"\u003e\n \u003cp\u003e0.454\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.211573236889693%\" valign=\"top\"\u003e\n \u003cp\u003e0.202\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.743218806509946%\" valign=\"top\"\u003e\n \u003cp\u003e5.049\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.5623869801085%\" valign=\"top\"\u003e\n \u003cp\u003e0.025\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.5623869801085%\" valign=\"top\"\u003e\n \u003cp\u003e1.575\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"18.806509945750452%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eTable 4 logistic analysis of NEC\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd width=\"18.772563176895307%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.288808664259928%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cem\u003eB\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.913357400722022%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cem\u003eSE\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.537906137184116%\" valign=\"top\"\u003e\n \u003cp\u003eWald\u003cem\u003e\u0026chi;2\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.35740072202166%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.35740072202166%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cem\u003eOR\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"18.772563176895307%\" valign=\"top\"\u003e\n \u003cp\u003e95%\u003cem\u003eCI\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"18.772563176895307%\" valign=\"top\"\u003e\n \u003cp\u003eVaginal delivery\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.288808664259928%\" valign=\"top\"\u003e\n \u003cp\u003e1.005\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.913357400722022%\" valign=\"top\"\u003e\n \u003cp\u003e0.490\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.537906137184116%\" valign=\"top\"\u003e\n \u003cp\u003e4.203\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.35740072202166%\" valign=\"top\"\u003e\n \u003cp\u003e0.040\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.35740072202166%\" valign=\"top\"\u003e\n \u003cp\u003e2.731\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"18.772563176895307%\" valign=\"top\"\u003e\n \u003cp\u003e1.045~7.137\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"18.772563176895307%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.288808664259928%\" valign=\"top\"\u003e\n \u003cp\u003e-2.251\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.913357400722022%\" valign=\"top\"\u003e\n \u003cp\u003e0.429\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.537906137184116%\" valign=\"top\"\u003e\n \u003cp\u003e27.514\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.35740072202166%\" valign=\"top\"\u003e\n \u003cp\u003e＜0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.35740072202166%\" valign=\"top\"\u003e\n \u003cp\u003e0.105\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"18.772563176895307%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"18.772563176895307%\" valign=\"top\"\u003e\n \u003cp\u003eGestational diabetes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.288808664259928%\" valign=\"top\"\u003e\n \u003cp\u003e1.056\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.913357400722022%\" valign=\"top\"\u003e\n \u003cp\u003e0.434\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.537906137184116%\" valign=\"top\"\u003e\n \u003cp\u003e5.926\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.35740072202166%\" valign=\"top\"\u003e\n \u003cp\u003e0.015\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.35740072202166%\" valign=\"top\"\u003e\n \u003cp\u003e2.876\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"18.772563176895307%\" valign=\"top\"\u003e\n \u003cp\u003e1.229~6.732\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"18.772563176895307%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.288808664259928%\" valign=\"top\"\u003e\n \u003cp\u003e-1.867\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.913357400722022%\" valign=\"top\"\u003e\n \u003cp\u003e0.261\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.537906137184116%\" valign=\"top\"\u003e\n \u003cp\u003e51.339\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.35740072202166%\" valign=\"top\"\u003e\n \u003cp\u003e＜0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.35740072202166%\" valign=\"top\"\u003e\n \u003cp\u003e0.155\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"18.772563176895307%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"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":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Delivery mode, Sepsis, Necrotizing enterocolitis, Prognosis, Extremely preterm infant","lastPublishedDoi":"10.21203/rs.3.rs-3790520/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-3790520/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eObjective:\u003c/strong\u003e To study the influence of the delivery mode on the short-term outcomes of extremely preterm infants, and to provide a basis for delivery mode selection. Methods: A total of 166 extremely preterm infants who were born from 2018 to 2022 were enrolled. According to the delivery mode, they were divided into two groups: natural birth group ( \u003cem\u003eN \u003c/em\u003e= 103 ) and caesarean birth group ( \u003cem\u003eN \u003c/em\u003e= 63 ) . A statistical analysis was performed for maternal data and short-term outcomes.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults:\u003c/strong\u003e Compared with the caesarean birth group, the natural birth group had significantly higher incidence rates of early-onset sepsis and necrotizing enterocolitis ( NEC ) ( \u003cem\u003eP\u003c/em\u003e＜0.05 ) . The logistic regression analysis showed that natural birth was an independent risk factor for early-onset sepsis and NEC ( \u003cem\u003eOR \u003c/em\u003e= 2.032 and 2.731 respectively，\u003cem\u003eP\u003c/em\u003e＜0.05 ) , and the gestational diabetes was an independent risk factor for NEC.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusions:\u003c/strong\u003e Caesarean birth decreased the incidence of early-onset sepsis and NEC in extremely premature infants and did not decrease the incidence rates of other adverse outcomes.\u003c/p\u003e","manuscriptTitle":"Influence of the delivery mode on the short-term outcomes of extremely preterm infants","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-01-03 13:38:56","doi":"10.21203/rs.3.rs-3790520/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"ed8dc160-0756-4a56-b6da-789416c9f058","owner":[],"postedDate":"January 3rd, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2024-05-15T09:14:26+00:00","versionOfRecord":[],"versionCreatedAt":"2024-01-03 13:38:56","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-3790520","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-3790520","identity":"rs-3790520","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}