Predicting the success of external cephalic version with a scoring system. A prospective, two-phase study.

OBJECTIVE

To develop a noninvasive and quantifiable scoring system based on clinical parameters to predict the success of external cephalic version (ECV) in women with breech presentation at term.

STUDY DESIGN

This was a prospective, two-phase, clinical study. Phase 1 was to develop a scoring system from 53 versions with singleton pregnancy in breech presentation at term using a standard protocol with fetal monitoring, ultrasound assessment and tocolysis. Phase 2 was to verify this scoring system by application to 88 versions using the same standard protocol as in phase 1.

RESULTS

The success rates for ECV in phases 1 and 2 were 64.2% and 61.4%, respectively, making the overall success rate 62.4%. The results of phase 1 showed that there were significant differences in the following parameters: head palpable, breech unengagement, symphysisfundal height and uterine relaxation. A scoring system based on these four clinical parameters was developed. When applied to 88 versions in the second phase, the likelihood ratio of successful ECV was > 30 if the version score was > or = 3 and < 1.8 if the version score was < or = 2.

CONCLUSION

Using our scoring system, prediction of successful ECV was possible without ultrasound scan or vaginal examination, and counseling could be given once breech presentation was diagnosed.