Trial of labor after two previous Cesarean deliveries: factors associated with success and characteristics of uterine rupture

Objective: To identify pre-labor factors associated with successful trial of labor after two prior cesarean deliveries (TOLAC-2) and to characterize maternal and neonatal outcomes, including all cases of uterine rupture. Study design.: A retrospective single-center cohort study (2011–2026). Women with two prior low-transverse cesarean deliveries who attempted TOLAC-2 under a strict protocol (spontaneous labor, vertex presentation, no induction or augmentation) were included. Pre-labor factors associated with TOLAC-2 failure were examined using multivariable logistic regression, with maternal age, body mass index, and gestational age analyzed continuously and a >41-week threshold in a secondary model. All uterine ruptures were reviewed individually. Results: Of 6047 women with two previous cesarean deliveries, 202 (3.3%) attempted TOLAC-2; 151 (74.8%) achieved vaginal delivery. Previous vaginal birth after cesarean (VBAC) was associated with lower odds of failure (aOR 0.3, 95% CI 0.1–0.7), and prior trial of labor before either previous cesarean with higher odds (aOR 3.1, 95% CI 1.2–7.8). Continuous gestational age was not independently associated with failure, whereas delivery >41 weeks was (aOR 2.7, 95% CI 1.1–7.0). Complete uterine rupture occurred in 9 of 202 attempts (4.5%, 95% CI 2.1–8.3%); seven were diagnosed at intrapartum cesarean delivery and two after vaginal delivery, none required hysterectomy, and all nine occurred during 2019–2026. Conclusion: In this highly selected cohort, three-quarters of TOLAC-2 attempts resulted in vaginal delivery. Previous VBAC was associated with lower odds of failure and prior labor with higher odds. The 4.5% rate of complete uterine rupture indicates that the attempt itself carries substantial risk, which should be central to counseling.