Objective: Much of the literature on clinical decision-making regarding the optimal route of delivery for periviable birth, 23 0/7-25 6/7 weeks gestation, has focused on neonatal risks. In fact, routine cesarean delivery at these early gestational ages has not been shown to improve neonatal mortality or neurological outcomes. Neonatal risks associated with the route of delivery are well known. Conversely, there is a paucity of data on maternal morbidity associated with the route of delivery. We examined maternal morbidity according to the attempted route of delivery in women undergoing periviable birth. Study design: In a secondary analysis of the Consortium on Safe Labor, a retrospective cohort study, maternal outcomes were compared between attempted vaginal delivery and planned cesarean delivery in women undergoing periviable birth. Analyses were repeated to compare maternal outcomes among actual mode of delivery (vaginal delivery versus cesarean delivery). Multivariable Poisson regression was used to estimate adjusted relative risks (aRR) with 95% confidence intervals (95% CI), controlling for predefined covariates. Results: Of 678 women who underwent periviable birth, 558 (82.3%) and 120 (17.7%) attempted vaginal delivery and planned cesarean delivery, respectively. Of 558 women who attempted a vaginal delivery, 411 (73.7%) achieved a vaginal delivery. Women who attempted a vaginal delivery compared to those who had a planned cesarean delivery were less likely to have endometritis (3.1 versus 15.0%; aRR 0.18, 95% CI 0.09-0.35). Women who attempted a vaginal delivery compared to those who had a planned cesarean delivery had 7-day shorter total length of hospital stay (p < .001). Comparison of actual mode of delivery showed that women with vaginal had decreased risks of fever (2.9 versus 7.9%; aRR 0.42, 95% CI 0.20-0.90), endometritis (0.5 versus 12.4%; aRR 0.03, 95% CI 0.01-0.13), and maternal thrombosis (0.2 versus 3.0%; aRR 0.08, 95% CI 0.01-0.93) compared to cesarean delivery. Women with vaginal delivery had 3-day shorter total length of hospital stay (p < .001) compared to cesarean delivery. Conclusion: The majority of women (73.7%) who attempted a vaginal delivery achieved a vaginal delivery. Attempting a vaginal delivery between 23 0/7 and 25 6/7 weeks gestation compared to a planned cesarean delivery was associated with decreased risks of maternal infectious morbidity. Deciding the route of delivery is challenging in women undergoing periviable delivery. Our analysis provides important information on short-term maternal risks when considering the risks and benefits during these discussions.
Keywords: Attempted route of delivery; cesarean delivery; maternal complication; periviable delivery.