Expecting identical twins and having few complications? Vaginal delivery is safe

Twins who share the same placenta, where the first baby is positioned head-down, can be safely delivered vaginally. The new data analysis of monochorionic twins, which are identical twins who share the same placenta, shows vaginal birth is safe for both the mother and her babies between 32 and 38 weeks of pregnancy.

“We used the best data available from the Twin Birth Study and specifically looked at monochorionic twins. The results clearly show that for uncomplicated monochorionic twins, between 32 and 38 weeks, when the first twin is head down, vaginal delivery is not associated with more risks for mom and baby than a caesarean section,” says Dr. Amir Aviram, maternal fetal medicine specialist at Sunnybrook and principal investigator of the study published in the American Journal of Obstetrics and Gynecology. “Clinicians and families now have evidence-based information when they are considering whether to have a vaginal delivery or Caesarian section for their babies.”

Data was provided from the Twin Birth Study, a prospective, randomized, controlled study, to compare outcomes of a trial of labor and elective Caesarian section delivery in monochorionic twins only. A total of 670 women between 32 to 38 weeks of pregnancy were randomized to either a planned Caesarian section or planned vaginal delivery. Women included had twin A in the cephalic position, positioned head down, and each twin had an estimated weight of 1500 to 4000 grams.

Results showed no difference in outcomes among the mothers, with outcomes for the babies from both modes of delivery very similar. Perinatal outcomes included birth weight, Apgar score and admission to a neonatal intensive care unit.

“This information is incredibly valuable for families expecting monochorionic twins,” says Victoria Leachman, who delivered identical twins at Sunnybrook on May 11, 2020. “Families want to ensure the safest delivery option for both the mom and her babies. This research, together with the expertise of their care team, will be a useful guide.”

Learn more about multiple pregnancy care and research at Sunnybrook »