Breech births increase fetal mortality rate compared to elective vaginal delivery

While a rise in cesarean section (C-section) delivery rates due to breech presentation has improved neonatal outcome, 40% of term breech deliveries in the Netherlands are planned vaginal deliveries. According to a new Dutch study that is published today in Acta Obstetricia et Gynecologica Scandinavica, a journal of the Nordic Federation of Societies of Obstetrics and Gynecology, there is a 10-fold increase in fetal mortality in vaginal delivery for breech presentation compared to elective C-section.

Up to 4% of deliveries are breech births-when the baby is delivered buttocks or feet first, instead of in the head-first position. A 2000 study by Hannah et al. was the largest, randomized controlled trial to examine the type of deliver on mother and infant outcomes. After the term breech trial reported a significant decrease in perinatal mortality among women who had a planned C-section compared to those opting for elective vaginal delivery, C-section rates increased dramatically.

In fact, medical evidence found that following publication of the term breech trial results, elective cesarean rates in Australia increased to 94% (2008) and in the Netherlands that rate rose from 50% to 78%. In the U.S., the overall cesarean rate climbed nearly 60% from 1996 to 2009 and in 2012 was at 33% of all deliveries according to the Centers for Disease Control and Prevention (CDC).

"As an obstetrician, ensuring the health and safety of the mother and infant during child birth is of the utmost importance," said lead study author Dr. Floortje Vlemmix from the Department of Obstetics and Gynecology, Academic Medical Center, University of Amsterdam in the Netherlands. "Our study focuses on understanding if the increase in ceseareans following the term breech study had any impact on neonatal outcomes."

For this retrospective study, researchers studied 58,320 women who had term breech deliveries at hospitals in the Netherland. The group included singleton term breech babies delivered between 37 and 42 weeks, but excluded infants who had any birth defects (congenital malformations) or stillbirths (antenatal death). Researchers used data from the Dutch national perinatal registry from 1999 to 2007, which includes 96% of all births in the Netherlands.

Findings indicate that elective C-section rates increased from 24% to 60%, resulting in a decrease of infant mortality from 1.3/1000 to 0.7/1000. Perinatal mortality remained the same in the group of planned vaginal deliveries. Researchers determined that there needed to be 338 cesareans to prevent one perinatal death. Further analysis could not identify pregnancy related factors that placed women at low versus high risk of poor neonatale outcome during vaginal breech birth.

"While elective C-section has improved neonatal outcomes there is still a good number of women who attempt vaginal birth," concludes Dr. Vlemmix. "Our findings suggest there is still room for improvement to prevent unnessary risk to the infant. We recommend using measures to turn the baby (external cephalic version) to prevent breech presentation at birth and counselling women who want to proceed with a vaginal breech birth."