Systematic review of adverse outcomes of external cephalic version and persisting breech presentation at term

The aim of this study was to determine the frequency of adverse maternal and fetal outcomes of both external cephalic version (ECV) and persisting breech presentation at term. We conducted a systematic review of the literature using Medline, Embase and All Evidence Based Medicine (EBM) Reviews databases. Data were extracted from studies that compared women who had an ECV from 36 weeks' gestation with a similar control group of women enrolled at the same gestational age, eligible for, but who did not have an ECV. Eleven studies with a total of 2503 women were included. Adverse outcomes related to ECV were rarely reported and in most studies there was no evidence that relevant outcomes were ascertained among similar women who did not have an ECV. There was no increased risk of antepartum fetal death associated with ECV, but numbers were small. There were no reported cases of uterine rupture, placental abruption, prelabour rupture of membranes or cord prolapse, but these outcomes were not examined among controls. Onset of labour within 24 h and nuchal cord was non-significantly higher among women who had an ECV compared with those with a persisting breech. Despite limited reporting and small numbers, the results of our review suggest that adverse maternal and fetal outcomes of both ECV and persisting breech presentation are rare. Only with improved reporting and collection of safety data on ECV and persisting breech presentation can we provide high-quality information to assist informed decision making by pregnant women with a breech presentation at term.