Intrapartum management of twin pregnancies: are uncomplicated monochorionic pregnancies more at risk of complications than dichorionic pregnancies?

OBJECTIVE: To analyze mode of delivery and neonatal morbidity according to chorionicity in a hospital birth center with a policy of vaginal delivery for twins. STUDY DESIGN: Retrospective analysis over a 13-year period. SETTING: Department of Obstetrics, University Hospital, Lille, France. POPULATION: In all, 1009 twin pregnancies were included, divided into 171 uncomplicated monochorionic pregnancies (17%) and 838 dichorionic pregnancies (83%). METHODS: We compared the monochorionic and the dichorionic populations. MAIN OUTCOME MEASURES: Rate of cesarean section and neonatal outcome (umbilical artery pH, Apgar score and neonatal complications). RESULTS: The rate of cesarean sections was 45.7% with no difference found based on chorionicity. The reasons for elective cesarean section were mainly noncephalic presentation, which was more frequent in dichorionic than in monochorionic (48.8% vs. 37.2%, p = 0.025) pregnancies. Birthweight was lower in monochorionic twins (2249 ± 469 g vs. 2329 ± 478 g, p = 0.045). The rate of umbilical artery cord blood values with a pH < 7.10 was similar in monochorionic and dichorionic pregnancies. There was no difference in neonatal complications between the two groups. CONCLUSION: Monochorionic and dichorionic twin pregnancies had similar delivery outcomes. The neonatal outcome for twin 2 was not different between monochorionic and dichorionic pregnancies. Vaginal birth could be offered to women with twin pregnancies regardless of chorionicity.