External cephalic version and spontaneous version rates: ethnic and other determinants

Abstract

Variable rates of external cephalic version (ECV) success in late pregnancy and of spontaneous version have been reported for different population groups. An ECV attempt by one operator in 80 patients beyond 36 weeks gestation was successful less frequently in white nulliparous patients and in those with lateral or cornual placental situation. A similar influence of ethnic and other variables was found on the spontaneous version rate in 108 patients in whom no ECV was attempted. Despite population differences in ECV success rates, the ratio of successful ECV to spontaneous version in reported randomized control trials is consistent at about 3:1.