External cephalic version and spontaneous version rates: ethnic and other determinants

Area of Science:

• Obstetrics and Gynecology
• Maternal-Fetal Medicine

Background:

• External cephalic version (ECV) is a procedure to turn a fetus from a breech to a cephalic presentation.
• Success rates for ECV and spontaneous version vary among different patient populations.
• Understanding these variations is crucial for optimizing obstetric interventions.

Purpose of the Study:

• To investigate the influence of patient demographics and placental factors on ECV success rates.
• To compare the rates of successful ECV with spontaneous version in late pregnancy.
• To analyze the consistency of the ECV to spontaneous version success ratio across different populations.

Main Methods:

• Retrospective analysis of 80 patients undergoing ECV beyond 36 weeks gestation.
• Analysis of spontaneous version rates in 108 control patients.
• Comparison of success rates based on ethnicity, parity, and placental location.

Main Results:

• ECV success was lower in white nulliparous patients and those with lateral or cornual placental presentations.
• Similar demographic and placental influences were observed on spontaneous version rates.
• The ratio of successful ECV to spontaneous version remained consistently around 3:1 in reported randomized trials.

Conclusions:

• Patient ethnicity and placental location significantly impact ECV success.
• These factors also influence spontaneous version rates, suggesting underlying physiological differences.
• Despite population-specific variations, the relative efficacy of ECV compared to spontaneous version is consistent.