Efficacy of a second external cephalic version (ECV) after a successful first external cephalic version with subsequent spontaneous reinversion to breech presentation: a retrospective cohort study

Objective Determining the efficacy of performance of a second external cephalic version (ECV) following successful first ECV with subsequent spontaneous reinversion to breech presentation in reducing the rate of cesarean delivery (CD). Methods Data were reviewed on healthy women with fetuses in breech presentation who underwent a first ECV after 36 weeks. Routine ultrasound study was performed at 39-week gestation, and a repeat ECV procedure was performed if the fetus had reverted to non-cephalic presentation. Obstetrical outcome measures were compared between women who underwent one successful ECV between 36- and 41-week gestation in which the fetus remained in cephalic presentation until labor and those who underwent a successful first ECV after which the fetus returned to breech and a second ECV was performed. The primary outcome was the rate of secondary CD during vaginal delivery in cephalic presentation; rate of successful second ECV was the secondary outcome. Results Overall 250 women underwent one ECV attempt of which 169 (67%) were successful. Of them 28 reverted to breech presentation, all women underwent two attempts of which 21 (76%) were successful. A second successful ECV attempt was associated with a 33% incidence of a CD vs. 2.8% after one successful ECV in which the fetus remained in cephalic presentation. Conclusion A second ECV after a successful first ECV with subsequent spontaneous reversion to breech presentation can be expected to be successful in 76% of cases but lead to CD in 33% of cases. Our findings can be used to support patient counseling and decision-making before second ECV attempt.