Induction of labor versus expectant management for women with a prior cesarean delivery

Objective Previous studies of induction of labor in the setting of trial of labor after cesarean have compared women undergoing trial of labor after cesarean to those undergoing spontaneous labor. However, the clinically relevant comparison is to those undergoing expectant management. The objective of this study was to compare obstetric outcomes between women undergoing induction of labor and those undergoing expectant management ≥39 weeks of gestation. Study Design This was a secondary analysis of data from the Eunice Kennedy Shriver National Institute of Child Health and Human Development Maternal-Fetal Medicine Units Network Cesarean Registry that included women with singleton gestations at a gestational age of ≥39 weeks and a history of 1 low transverse cesarean delivery. Outcomes of induction at 39, 40, and 41 weeks were compared to expectant management beyond each gestational age period using univariable and multivariable analyses. Women with scheduled repeat cesarean deliveries done for the indication of prior cesarean delivery were excluded from the analysis. Results In all, 12,676 women were eligible for analysis. The rate of vaginal birth after cesarean (VBAC) was higher among women undergoing induction of labor at 39 weeks compared to expectant management (73.8% vs 61.3%, P <.001). The risk of uterine rupture also was higher among women undergoing induction of labor at 39 weeks compared to expectant management (1.4% vs 0.5%, P =.006, respectively). In multivariable analysis, induction of labor at 39 weeks remained associated with a significantly higher chance of VBAC and uterine rupture (odds ratio, 1.31; 95% confidence interval, 1.03-1.67; and odds ratio, 2.73; 95% confidence interval, 1.22-6.12, respectively). Conclusion Induction of labor at 39 weeks, when compared to expectant management, was associated with a higher chance of VBAC but also of uterine rupture.