Rates of Cesarean Conversion and Associated Predictors and Outcomes in Planned Vaginal Twin Deliveries

Twin vaginal deliveries (VDs) are often performed in the operating room (OR) given the risk of conversion to cesarean delivery (CD) for the aftercoming twin. We aim to investigate the rates of conversion to CD for planned twin VDs and identify predictors and outcomes of conversion.

A retrospective cohort study of all women who underwent a planned twin VD at two large academic medical centers over 4 years. Demographic and outcome data were chart abstracted. Various statistical tests were used to evaluate the influence of perinatal variables on mode of delivery and identify possible predictors of conversion.

Eight hundred and eighty-five twin deliveries were identified, of which 725 (81.9%) were possible candidates for VD. Of those, 237 (32.7%) underwent successful VD of twin A. Ninety-five (40.1%) had a nonvertex second twin at time of delivery. Conversion to CD occurred in 10 planned VDs (4.2%). Conversions were higher with spontaneous labor (relative risk [RR]: 2.1; 95% confidence interval [CI] 1.6-2.7; p = 0.003), and having an intertwin delivery interval greater than 60 minutes (RR: 5.1; 95% CI: 2.5-10.8; p < 0.001). Nonvertex presentation of twin B, type of delivery provider, or years out in practice of delivery provider were not significantly different between groups. There were no significant differences in neonatal outcomes between VD and conversion groups. There was a significant association between use of forceps for twin B and successful VD (p = 0.02), with 84.6% in the setting of a nonvertex twin B.

Successful VD was achieved in planned VD of twins in 95.8% of cases, and there were no significant differences in maternal and fetal outcomes between successful VD and conversion to CD for twin B. With the optimal clinical scenario and shared decision-making, performing vaginal twin deliveries in labor and delivery rooms should be discussed.

· There is a propensity to perform twin vaginal deliveries in the operating room.. · Rates of conversion to cesarean section are very low.. · There are no significant differences in perinatal outcomes with conversion..