From the Research
Flexed breech positions have a significantly higher success rate during External Cephalic Version (ECV) compared to extended breech positions, primarily due to the distribution of fetal mass and the compact lower pole that can rotate more easily during the procedure. The most recent and highest quality study, 1, found that the success rate of ECV was significantly higher in women without persistent breech presentation, with a success rate of 82.0% compared to 19.6% in those with persistent breech presentation. This study highlights the importance of fetal position in determining the success of ECV.
Key Factors Influencing ECV Success
- Fetal position: Flexed breech positions are more likely to result in successful ECV due to the compact lower pole and uniform contour that responds better to external pressure.
- Maternal parity: Multiparity is associated with a higher success rate of ECV, as found in studies 2 and 3.
- Tocolytic medications: The use of tocolytic medications such as terbutaline or nifedipine can enhance success rates regardless of breech type, as mentioned in study 4.
Clinical Implications
- ECV should be attempted in all women with breech presentation at term, as it is associated with a decreasing rate of breech presentation at birth and potentially a lower rate of cesarean section, as recommended in study 4.
- The procedure should be performed with immediate access to an operating room for emergency cesarean, and cardiotocography should be performed prior to and during 30 minutes after the procedure, as suggested in study 4.
- Parenteral tocolysis should be used to increase the success rate of ECV, as recommended in study 4.