Predictors of successful vaginal birth after a caesarean in women with a previous single caesarean delivery.

OBJECTIVE: The aim of our study was to present our case series of the trial of labor after a caesarean (TOLAC) and determine significant predictors for a successful vaginal birth after a caesarean (VBAC). PATIENTS AND METHODS: Women with previous single caesarean deliveries who underwent TOLAC between January 2016-December 2019 were included in the study (n = 474). All files were analyzed in terms of demographic characteristics, obstetric history, history of index pregnancy and medical characteristics of previous caesarean delivery. For each current pregnancy, we recorded time from the previous delivery, the BISHOP and TOLAC scores at admission, induction of labor, gestational age at delivery, estimated fetal weight, intrapartum characteristics, mode of delivery and intra-operative findings. RESULTS: Among 474 women who had a previous caesarean delivery and gave consent for TOLAC, 216 resulted in a successful vaginal delivery, whereas 258 underwent repeat caesarean delivery. One hundred and seventy-nine women gave up trial of vaginal delivery during labor. The success rate of VBAC after exclusion of caesarean cases due to maternal requests was 73.2%. The induction rate was significantly higher in cases with successful VBAC (40% vs. 29.1%). The risk of uterine rupture was 0.42% in cases with labor induction. ROC analysis showed significant predictive values of the TOLAC score, body mass index (BMI), the number of previous VBACs and the number of previous vaginal deliveries, birth weight and the BISHOP score at admission. CONCLUSIONS: Our data showed us that major determinants for successful VBAC following labor are the BISHOP score at admission, number of previous vaginal deliveries, body mass index, birth weight and the TOLAC score calculated at admission.