The feasibility of a Trial of Labor after Two Cesarean deliveries. Outcomes and prognostic factors for success.

To determine whether a trial of labor after two cesarean deliveries increases the risk of adverse maternal and neonatal outcomes and identify prognostic factors for TOLAC2 success.A retrospective cohort study was conducted The study group was comprised of women with two caesarean deliveries who attempted TOLAC (TOLAC2). Outcomes were compared to women undergoing TOLAC after one previous cesarean delivery (TOLAC1). The primary outcome was TOLAC success. Secondary outcomes included mode of delivery, uterine rupture, and combined adverse outcome(CAO) (uterine rupture, PPH, 5 minute Apgar < 7, pH < 7.1). Logistic regression was used for the multivariate analysis to identify prognostic factors for TOLAC2 success. 381 women who underwent TOLAC2 were compared to 3635 women who underwent TOLAC1. Women attempting TOLAC2 were less likely to achieve VBAC (80.8% and 92.5% OR 0.35 95% CI 0.26-0.47 p<0.001) and more likely to experience uterine rupture (0.8%Vs0.2% OR 4.1 95% CI 1.1-15.9 p=0.02) but not CAO (4.2% Vs 4.8% OR 0.88 95% CI 0.5-1.5 p=0.3). TOLAC2 women with no previous vaginal deliveries had a lower chance of VBAC and a higher risk of uterine rupture compared to TOLAC1 patientswomen without a prior vaginal delivery (45.2% vs 86.3% OR 0.13 95% CI 0.07-0.25 p<0.001) (2.3% Vs 0%) and TOLAC2 women with a prior vaginal delivery(45.2% Vs 85.3% OR 0.14 95% CI 0.1-0.3 p<0.0001) (2.4% Vs 0.6% OR 4.1 95% CI 0.4-46.3 p=0.3). Multivariate analysis revealed that a history of vaginal delivery is an independent predictor of TOLAC 2 success. Women attempting TOLAC2 are less likely to achieve VBAC and are at greater risk of uterine rupture compared to those attempting TOLAC1. Prior vaginal delivery seems to have a protective effect on TOLAC outcomes. This data should be used to counsel patientswomen and assist in decision-making when considering the mode of delivery in patientsw.