Planned cesarean or vaginal delivery for women in spontaneous labor with a twin pregnancy: A secondary analysis of the Twin Birth Study

BACKGROUND: The Twin Birth Study, a multicenter randomized controlled trial, found no differences in neonatal outcomes in women with twins randomized to planned cesarean or vaginal delivery. Nevertheless, women who present in spontaneous labor might expect a better outcome following a trial of vaginal delivery than undergoing cesarean delivery. In this secondary analysis, we aimed to compare neonatal outcomes of women who presented in spontaneous labor in the two arms of the Twin Birth Study. METHODS: Women in whom the first twin was in the cephalic presentation were randomized between 32 + 0 and 38 + 6 weeks to planned vaginal delivery or cesarean. The primary outcome was a composite of fetal or neonatal death or serious neonatal morbidity. RESULTS: Of the 2804 women included in the Twin Birth Study, 823 women in the planned vaginal delivery arm and 612 in the planned cesarean arm presented in spontaneous labor. Although the odds ratio favored planned vaginal delivery, there was no statistically significant difference in the rate of primary outcome between the vaginal delivery and cesarean arms (1.8% vs 2.7%, respectively; P = 0.16; OR 1.49; 95% CI, 0.87-2.55). Similarly, the rates of the individual components of the primary outcome and of maternal adverse outcome were similar between the two arms. CONCLUSION: In women with twins who present in spontaneous labor between 32 + 0 and 38 + 6 weeks' gestation, where the first twin is cephalic, a policy of planned vaginal delivery or cesarean is not associated with significant differences in neonatal or maternal outcomes.