Introduction: Epidural analgesia has been considered a risk factor for labor dystocia at trial of labor after cesarean (TOLAC) and uterine rupture. We evaluated the association between exposure to epidural during TOLAC and mode of delivery and maternal-neonatal outcomes.
Materials and methods: A single center retrospective study of women that consented to TOLAC within a strict protocol between 2006 and 2013. Epidural "users" were compared to "non-users". Primary outcome was the mode of delivery: repeat in-labor cesarean or vaginal birth after cesarean (VBAC). Secondary outcomes were maternal/neonatal morbidities. Univariate/multivariate analyses for associations between epidural and mode of delivery were adjusted for significant covariates/mediators.
Results: Of a total of 105,471 births registered, 9464 (9.0%) were eligible for TOLAC; 7149 (75.5%) women consented to TOLAC, among which 4081 (57.1%) had epidural analgesia. The in labor cesarean rate was significantly lower for the epidural "users" 8.7% vs. "non-users" 11.8%, P<0.0001, with a parallel increased rate of instrumental delivery. Uterine rupture rates were comparable: 0.4% and 0.29%, respectively (P=0.31). The adjusted multivariate model showed that epidural "users" were more likely to experience a VBAC, odds ratio (OR) 4.58 [3.67; 5.70]; P<0.0001 with a similar rate of adverse maternal-neonatal outcomes.
Conclusion: Epidural analgesia at TOLAC may emerge as a safe and significant adjunct for VBAC.
Keywords: Cesarean section; TOLAC; VBAC; epidural analgesia; uterine rupture; vaginal delivery.