Predictors of successful external cephalic version in an Australian maternity hospital

Abstract

There are minimal data involving predictors of success of external cephalic version (ECV) in an Australian healthcare setting. To determine the predictors of successful ECV as well as the success rate of ECV and the mode of, and presentation at, delivery for women undergoing ECV for breech presentation from 36-weeks gestation. A prospective review was carried out on all women who had undergone ECV from 36-weeks gestation at the Mater Mothers Hospital over an 8-year period from 2001 to 2008. Data were collected prospectively and were collated in conjunction with database review, chart review and telephonic patient interviews. A total of 355 women underwent ECV for breech presentation. The overall success rate was 66% (57% for nulliparous, 76% for multiparous). A woman who underwent ECV had a 46% chance of a vaginal birth. If the ECV was successful, she had a 70% chance of vaginal birth. From bivariate analysis, parity, amniotic fluid index (AFI) and estimated fetal weight (EFW) were determined to be possible predictors of success of ECV and were included in the logistic regression modelling. In the regression analysis, multiparity increased the odds of successful ECV by 2.18. For every one unit increase in AFI, the odds of successful ECV increased by 1.18. Multiparity and amniotic fluid volume as assessed by AFI were the significant predictors of immediate success of ECV. Conversely, lower AFI and nulliparity are factors that are likely to reduce the likelihood of successful ECV.