Complicated primary cesarean delivery increases the risk for uterine rupture at subsequent trial of labor after cesarean

Purpose: To evaluate whether cesarean delivery (CD) indication, labor status, and other primary CD characteristics affect the risk for uterine rupture in subsequent deliveries. Methods: A case–control study of women attempting trial of labor after cesarean (TOLAC) in a single, tertiary, university-affiliated medical center (2007–2016). Deliveries complicated by uterine rupture were matched to successful vaginal birth after cesarean (VBAC) deliveries in a 1:3 ratio. Indication, labor status and post-partum complications (postpartum hemorrhage and postpartum infection) at primary CD were compared between study and control group. Results: During study period, there were 75,682 deliveries, of them, 3937 (5.2%) were TOLAC. Study group included 53 cases of uterine rupture at TOLAC and 159 women with successful VBAC. Women in study group had significantly lower rates of previous VBAC (15.1 vs. 28.9%, p = 0.047). Rate of postpartum complications at primary CD was significantly higher in women with TOLAC complicated by uterine rupture (7.5 vs. 1.9%, respectively, p = 0.042). Utilizing the multivariate logistic regression analysis, postpartum complications remained an independent risk factor for uterine rupture in the following TOLAC (aOR 4.07, 95% CI 1.14–14.58, p = 0.031). Conclusion: Postpartum hemorrhage and infection, in primary CD, seem to be associated with increased risk for uterine rupture during subsequent TOLAC.