Picking Their Birthday: Timing of Twin Delivery

By Eva Martin, MD of Elm Tree Medical, Inc.

Most of our parents didn’t get to choose our birthdays, but in the case of scheduled deliveries, exactly which day to plan for delivery is an important question for doctors and patients. The American College of Obstetrics and Gynecology (ACOG) and the Society for Maternal Fetal Medicine (SMFM) currently recommend delivery for dichorionic-diamniotic (di-di) twins during the 38th week of pregnancy. A new meta-analysis calls this recommendation into question, with results suggesting that delivery at 37 weeks could decrease stillbirths.

Dr. Cheong-See and her fellow researchers at Queen Mary University of London completed a systematic review and meta-analysis of 32 studies. Using data from 35,171 twin pregnancies, the authors compared the risk of stillbirth before each possible delivery date with the risk of neonatal death after each possible delivery date. For uncomplicated, di-di twin pregnancies after 34 weeks gestation, the risks balanced at 37 weeks. At 37 weeks, the risk of stillbirth was 3.4/1000 and essentially balanced with the risk of death from delivery. At 38 weeks, the risk of stillbirth increased to 10.6/1000 and was significantly more than the risk of neonatal death, which was 1.5/1000.

For monochorionic twin pregnancies, ACOG and SMFM recommend delivery at 34-36 weeks gestational age. The findings from the new meta-analysis agreed with the current recommendations. After 36 weeks, the study showed a trend towards more stillbirth than neonatal death.

Do we expect ACOG and SMFM to change their recommendations? Not so fast. The study examined the risk of death, but not the risk of complications, such as respiratory distress, which can result from preterm delivery. Before making any big changes, more research is needed to examine whether the twins’ health is also better at 37 versus 38 weeks. Health complications are much more common than death, which is relatively rare, so an increase in morbidity from early delivery could outweigh the benefits in mortality.

We want to hear from you! At what age do you recommend delivery of di-di twins? Have you noticed any trends in how twin pregnancies fare based on the delivery timing?