(239) Perinatal Outcomes of Myelomeningocele by Mode of Delivery in the United States

The optimal mode of delivery for fetuses with myelomeningocele remains uncertain. Our study aimed to compare perinatal outcomes of newborns with myelomeningocele by mode of delivery in a contemporary United States (US) cohort.

Study Design:

A retrospective cohort used population-based data from the US Natality Database on live singleton births complicated by myelomeningocele (2017-2021). Data was stratified to vaginal versus planned cesarean delivery. Cases delivered by cesarean after a failed trial of labor or unknown trial of labor attempt were excluded. The primary outcome was adverse perinatal composite, including preterm birth < 37 and < 34 weeks, chorioamnionitis, 5-minute Apgar score < 3, NICU admission, immediate and >6 hour assisted ventilation use, surfactant use, neonatal seizures, and neonatal mortality. Our secondary outcome included each component of the composite. Neonatal death was defined at the time of the birth certificate reporting. Multivariable logistic regression compared outcomes between vaginal and cesarean groups, adjusting for potential confounders.

Results:

Of the 13,368,848 births included, 1,559 (0.012%) were affected by myelomeningocele. Delivery mode was planned cesarean in 939 (60%) and vaginal in 492 (32%). Examining gestational age at birth in newborns with myelomeningocele, 457 (29%) were < 37 weeks, and 179 (39%) < 34 weeks. Vaginal birth was associated with lower odds of adverse perinatal composite compared with planned cesarean birth (Table 1). Evaluating individual components of the composite, vaginal delivery was associated with a higher rate of chorioamnionitis and planned cesarean delivery was associated with high rate of respiratory adverse outcomes. Additionally, vaginal delivery was associated with higher odds of seizures and neonatal death compared to planned cesarean delivery.

Conclusion:

Patient counseling on delivery planning for pregnancies complicated by myelomeningocele should include a discussion of potential adverse outcomes individualized to patients in the shared-decision-making process.