OC184: Emergency cerclage in cases with short cervix at the time of fetoscopic surgery in twin‐to‐twin transfusion syndrome and its relationship to perinatal outcome

Abstract

Short cervical length before treatment is an independent risk factor for preterm delivery in twin-to-twin transfusion syndrome (TTTS) treated by fetoscopic selective laser coagulation (FSLC) of placental anastomoses. We aimed to evaluate the impact of emergency cerclage on perinatal outcome in cases presenting with cervical length < 5th centile at the time of laser surgery. Observational study of severe TTTS cases diagnosed before 26 weeks of gestation and treated by FSLC between 1999 and 2007 in one center. Transvaginal sonographic measurement of cervical length prior to treatment identified cases with cervical length < 5th centile at the time of laser. Expectant management was applied to these cases prior to 2004 and a McDonald suture was placed immediately after laser surgery from 2004 onwards. Outcome was compared in patients with and without cerclage. Among the 272 women with cervical measurement included, the mean (SD) cervical length was 36 (+/− 11) mm. Cervical length was a strong predictor for gestational age at delivery (P = 0.005). The 5th centile was 15 mm and 14 patients had a cervix shorter than this cut-off value. There were 9 (64%) and 5 (36%) patients with and without cerclage respectively. GA at laser therapy was comparable between groups (157(+/− 6)) and 155(+/− 5)) days respectively (P = 0.8) and GA at delivery was 213(+/− 30) and 161(+/− 18) days in patients with and without cerclage respectively (P = 0.0019). The mean (IC 95%) prolongation of pregnancy in patients with cerclage was 51 days [23–79]. There were 16 (89%) and 4 (40%) survivor twins in patients with and without cerclage respectively (P = 0.01). In TTTS treated by laser, cervical length before treatment is significantly associated with gestational age at delivery. In patients with cervix < 15mm, emergency cerclage may prolong the pregnancy by up to 7 weeks.