Consider turning breech presentations at 34-36 weeks

Question Does earlier external cephalic version reduce breech presentation at birth and the rate of caesarean deliveries?

Synopsis One way to reduce the caesarean delivery rate is to prevent breech presentation at the time of birth. External cephalic version (ECV) at term is an established way to do that, but it is not highly successful. In this randomised controlled (non-blinded) study, performed in 25 centres in seven countries, 232 women with breech presentation identified at 34 to 36 weeks' gestation were randomised (allocation concealed) to early ECV at 34 to 36 weeks versus 37 to 38 weeks. Analysis was by intention to treat. Repeat procedures were allowed. There were 100 procedures in the early group compared with 78 in the late group. The study was powered to detect an absolute decrease in non-cephalic presentation at birth of 25%. The results showed an absolute difference of 9% (57% in the early group v 66% in the late group; relative risk 0.89; 95% confidence interval 0.70 to 1.05; P = 0.09). The caesarean delivery rates were 65% in the early group and 72% in the late group, again not statistically significant, but clinically meaningful if true. About three ECV procedures were performed for each 1% decrease in caesarean delivery rate. No differences in adverse effects were observed between groups.

Bottom line In this study, there was a trend for women undergoing external cephalic version for breech presentation starting at 34 to 36 weeks rather than at 37 or more weeks to have a cephalic presentation at the time of birth. A larger study is needed to prove whether the 7% absolute difference in observed caesarean delivery rate is a valid estimate.

Level of evidence 2b (see www.infopoems.com/resources/levels.html); individual cohort study or low quality randomised controlled trials < 80% follow up.

Hutton EK, Kaufman K, Hodnett E, et al. External version beginning at 34 weeks' gestation versus 37 weeks' gestation: a randomized multicenter trial. Am J Obstet Gynecol 2003;189: 245-54