Mode of Delivery in Previable Births.

OBJECTIVE: Preterm birth before 23 weeks of gestation typically results in neonatal death (5% survival). Society for Maternal-Fetal Medicine and American College of Obstetricians and Gynecologists published consensus guidelines recommending cesarean delivery (CD) not be performed for fetal indications between 20 and 226/7 weeks given the lack of proven benefit. We sought to quantify the previable CD rate and identify characteristics associated with previable CD.

METHODS: We performed a population-based retrospective cohort study of all live births in Ohio (2006-2015). Frequency of previable CD was stratified by week of gestation, defined as delivery between 16 and < 23 weeks of gestation. Maternal, obstetric, and neonatal characteristics were compared between women who underwent vaginal delivery versus CD. Multivariable logistic regression estimated the relative influence of maternal and fetal factors on the outcome of CD among previable live births.

RESULTS: Of 1,463,506 live births in Ohio during the 10-year study period, 2,865 births (0.2%) occurred during the previable period of 16 to 22 weeks. Nearly 1 in 10 live births at less than 23 weeks was delivered by cesarean ( n  = 273/2,865), CD rate 9.5% (95% confidence interval, 8.5-10.7). At 16 to 22 weeks of gestation, the CD rates were 0, 5.5, 7.6, 3.5, 5.4, 10.1, and 15.1%, respectively. Factors associated with CD included increasing parity, increasing birth weight, maternal corticosteroid administration, and fetal malpresentation. Previable neonates born by CD were more likely to be admitted to the NICU, receive ventilator support, and more likely to be living at the time of birth certificate filing.

CONCLUSION: Nearly 1 out of 10 births during the previable period was delivered via cesarean. Factors associated with previable CD suggest intent for neonatal interventions, such as NICU admission and supportive therapies. Our findings support that education and adherence with guidelines for care of previable births are a potential area of focus for perinatal quality improvement efforts.