Introduction: Success rates of external cephalic version (ECV) are heterogenous in the published literature. Some individual factors are already known to be associated with ECV success but probably do not fully explain the differences. The objective of this review is to assess the association between hospitals’ cesarean delivery rates for breech presentations after ECV failure and their ECV success rates.
Material and methods: We performed a review of the literature using the Medline and Cochrane Library computer databases and by searching on clinicaltrials.gov, from 1985 through 2020. This analysis included all studies reporting ECV success rates and cesarean delivery rates for breech presentations. The prognostic factors for successful ECV, such as rates of nulliparity, gestational age at ECV, BMI, and tocolysis use, were also collected and analyzed. Median ECV success rates from the included studies were compared according to these factors. The cesarean rate for persistent breech presentation after ECV failure reported in these studies was considered a proxy indicator of the unit’s policy for breech presentations. The correlation between ECV success rates and cesarean delivery rates was analyzed and is presented as a scatter plot.
Results: This analysis included 22 studies reporting rates of both successful ECV and cesarean deliveries for persistent breech presentation after ECV failure. The ECV success rates ranged from 16.3% to 82.5% with a median of 48.8% (interquartile range: 36.9-62.9). The median ECV success rate was higher in the studies that used tocolysis than in those that did not (51.3% versus 22.0%, P = .001) and in the studies with the highest cesarean rates for breech presentations than in those with the lowest cesarean rates (57.9% versus 36.2%, P = .006). The ECV success rates were significantly correlated with cesarean delivery rates for persistent breech presentations (R = 0.67; P = .001).
Conclusion: The likelihood of successful ECV appears higher in hospitals with policies that generally result in cesarean delivery for persistent breech presentation.