Prediction of Success of External Cephalic Version after 36 Weeks

We aimed to develop a predictive model for the chance of a successful external cephalic version (ECV). We performed a prospective cohort study of women with a singleton fetus in breech presentation with a gestational age of 36 weeks or more. Data on parity, maternal age, body mass index, ethnicity, gestational age, placental location, fetal position, estimated fetal weight, and amniotic fluid were recorded in all participants. Multivariable logistic regression analysis with a stepwise backward selection procedure was used to construct a prediction model for the occurrence of successful ECV. We included a total of 310 women. Multivariable logistic regression analysis demonstrated that multiparity, increasing estimated fetal weight, and normal amniotic fluid were favorable predictors of successful ECV. Anterior placenta location was an unfavorable predictor for ECV outcome. Discrimination of the model was fair (area under the curve 0.71), and the calibration of the model was acceptable. Our prediction model appears to discriminate between women with a poor chance of successful ECV (less than 20%) and women with a good chance of success (more than 60%). When this model is validated externally, it could be used for patient counseling and clinical decision making.