626: Success and safety of trial of labor after cesarean section in twin gestations

Abstract

Trial of labor after cesarean section (TOLAC) is considered a safe option for women with singleton pregnancies. However, there is no consensus as to the safety of TOLAC in patients with twin gestations. The aim of this study is to determine the safety and success rate of TOLAC in twin pregnancies. A retrospective cohort study of all women with twin pregnancies and a single prior cesarean delivery that underwent TOLAC at two tertiary centers between 2012-2018. Each case of twin gestation (study group, n=40) was matched to 2 cases of singleton pregnancy with one prior cesarean delivery (singleton control group, n=80) and to 2 cases of twin gestation with one prior cesarean delivery who underwent elective cesarean delivery (ECD control group, n=80). The primary outcome measure was the rate of successful vaginal birth. Secondary outcome measures included uterine rupture, maternal blood transfusion and neonatal mortality and morbidity outcomes including 5 minutes Apgar score, arterial cord PH and NICU admission. The study group and the singleton control group had comparable rates of induction of labor (17.5 vs 21.2% respectively, p=0.8) and of previous vaginal birth after cesarean (VBAC), (32.5% in both groups, p=0.86). The success rate of VBAC did not differ between the two groups (85% in the study group vs 71.2% in the singleton group, p=0.15). No cases of uterine rupture were noted in any of the groups, and rates of maternal blood transfusion were also comparable. The rates of Apgar score ≤ 7 and arterial cord PH< 7.1 did not differ significantly between the study and the ECD groups. However, NICU admission rates of the second twin were higher in the study group compared to the ECD group. (1st twin: 20 vs. 7.5%, p=0.09; 2nd twin: 25% vs. 6.2%, p=0.008). TOLAC in twin gestation appears to be an overall safe option and the rate of successful vaginal delivery in this group is as high as in singleton pregnancies undergoing TOLAC. The finding of higher NICU admission rate in the TOLAC compared to ECD group may be attributed to prematurity but requires further investigation.View Large Image Figure ViewerDownload Hi-res image Download (PPT)