Mode of delivery at periviability and early childhood neurodevelopment.

OBJECTIVE: Little is known regarding the impact of mode of delivery in the periviable period. Even less is understood regarding the effect of mode of delivery on neurodevelopment. Our objective is to determine if the mode of delivery at time of periviability impacts Bayley II scores at 2 years of age.

STUDY DESIGN: This is a secondary analysis of a randomized, controlled trial of magnesium sulfate for the prevention of cerebral palsy, a multicenter trial where women at imminent risk for delivery were assigned to receive magnesium sulfate or placebo. For this secondary analysis we included nonanomalous singleton gestations delivered between 23 4/7 and 25 6/7 weeks. We excluded women with missing exposure or outcome data. The primary exposure of interest was mode of delivery. The primary outcome was Bayley II scores <70 (mental and motor) at 2 years of age. Log binomial regression was used to control for possible confounders including gestational age at delivery, presentation at time of delivery, chorioamnionitis, years of maternal education, maternal body mass index, and original study treatment group.

RESULTS: A total of 158 women met inclusion criteria. In all, 91 had a vaginal delivery and 67 had a cesarean delivery. Exposure to magnesium sulfate, maternal education, chorioamnionitis, years of maternal education, and maternal body mass index were similar in both groups. There was no difference in either mental or motor Bayley II scores <70 or <85 by mode of delivery in either univariable or multivariable analysis.

CONCLUSION: There is no detectable difference in Bayley II scores between mode of delivery at time of periviability. This adds to the literature supporting obstetric indications dictating mode of delivery at this gestational age.