Outcomes after transabdominal cerclage in twin pregnancy with previous unsuccessful transvaginal cerclage

Transabdominal cerclage (TAC) is reported to be effective for preventing preterm birth in women with unsuccessful transvaginal cerclage (TVC) history. However, TAC has rarely been performed in twin pregnancy given the lack of sufficient evidence and the technical difficulty of the operation. Thus, it is unclear whether TAC is an effective procedure for twin pregnancy in women with a history of unsuccessful TVC. The aim of this study is to compare the characteristics and pregnancy outcomes after TAC in twin pregnancy versus singleton pregnancy, to examine whether twin pregnancy is a risk factor for very preterm birth (before 32 weeks) after TAC, and to determine whether TAC is effective in preventing preterm birth in twin pregnancy. This single-center retrospective cohort study included women who underwent TAC because of unsuccessful TVC history between January 2007 and June 2018. Of 165 women who underwent TAC, 19 had twins and 146 had singletons. Our results showed that the neonatal survival rate improved dramatically when TAC was performed (15.4% (prior pregnancy) vs 94.0% (after TAC) in twins, p<0.01; 22.8% (prior pregnancy) vs 91.1% (after TAC) in singletons, p<0.01). Moreover, the risk of very preterm birth was significantly decreased after TAC in both groups (36/39 (92.3%) (prior pregnancy) vs 2/19 (10.5%) (after TAC) in twins, p<0.01; 290/337 (86.1%) (prior pregnancy) vs 17/146 (11.6%) (after TAC) in singletons, p<0.01). More advanced maternal age and history of prior preterm delivery between 26+0 and 36+6 weeks were independently associated with very preterm birth, whereas the presence of a twin pregnancy was not associated with very preterm birth on multivariate logistic regression analysis. These results suggest that TAC is associated with successful prevention of very preterm birth and improved neonatal survival rates in the absence of procedure-related major complications in women with twin pregnancy and previous unsuccessful TVC history.