The term breech: vaginal or cesarean delivery?

The Term Breech Trial has been hailed for shining light on the murky question of how best to deliver term breech infants. But does it really?

Dr. Vidaeff is maternal-fetal medicine fellow and Dr. Yeomans is associate professor, department of OBG, division of maternal-fetal medicine, at the University of Texas in Houston. Dr. Mozurkewich is a lecturer in the department of OBG at the University of Michigan School of Medicine in Ann Arbor.

Dr. Mozurkewich is a lecturer in the department of OBG at the University of Michigan School of Medicine in Ann Arbor.

Until Mary E. Hannah and her colleagues conducted the randomized controlled study known as the Term Breech Trial (published in the October 21, 2000, issue of the Lancet), data on the best delivery method for breech infants at term were sketchy and conflicting. Still, elective cesarean generally was preferred when the breech presentation was footling; the fetus was large, compromised, or had a congenital abnormality that could complicate vaginal delivery; or when a physician experienced in vaginal breech delivery was unavailable. However, the optimal mode of delivery for all other term breech fetuses remained unclear at best—at worst, controversial.

The Term Breech Trial spanned 26 countries and involved 2,088 women with a frank or complete breech presentation at term (37 weeks and later). Of the 1,041 women allocated to planned cesarean delivery, 941 (90.4%) were delivered by C-section, while 591 of the 1,042 women (56.7%) assigned to the vaginal group were delivered vaginally. An experienced clinician was present during all vaginal deliveries. The primary outcomes analyzed were perinatal or neonatal mortality and serious neonatal morbidity, which were significantly lower for the planned-cesarean group than for the vaginal-delivery group (1.6% versus 5%). For the outcomes of maternal mortality and serious maternal morbidity, there were no real differences between the groups.