Five studies involving 2 187 women were included in a Cochrane review [Abstract] 1. One study reported on external cephalic version (ECV) that was undertaken and completed before 37 weeks' gestation compared to no ECV. No difference was found in the rate of non-cephalic presentation at birth. One study reported on a policy of ECV that was initiated before term (33 weeks) and up until 40 weeks' gestation and which could be repeated up until delivery compared to no ECV:a decrease in the rate of non-cephalic presentation at birth was found (relative risk 0.59, 95% confidence interval 0.45 to 0.77). Three studies reported on ECV started at between 34 to 35 weeks' gestation compared with beginning at 37 to 38 weeks' gestation. Pooled results suggested that early ECV reduced the risk of non-cephalic presentation at birth, failure to achieve vaginal cephalic birth, and vaginal breech delivery (high quality evidence in alla) T1. The difference between groups for risk of caesarean was not statistically significant (high quality evidence). There was evidence that risk of preterm labour was increased with early ECV compared with ECV after 37 weeks (6.6% vs 4.3%; RR 1.51, 95% CI 1.03 to 2.21; 3 trials, n=1888; evidence graded high quality). There was no clear difference between groups for low infant Apgar score at five minutes or perinatal death (stillbirth plus neonatal mortality up to seven days) (evidence graded as low quality for both outcomes).
A retrospective cohort study of 18 years 2 3308 women with breech presentation. 2614 women underwent ECV. Ineligibility for ECV occurred in 117 breech presentations (3.9%), and 297 eligible women (10.2%) declined it. ECV was successful in 1280 (49.0%, 95% CI 47.0-50.9%) (40% in nulliparous women; 64% in others); 1234 (97.3%) were cephalic at birth. Reversion after successful ECV occurred in 2.2%. In women with a successful ECV whose fetus remained cephalic at birth, 85.7% delivered vaginally. The corrected perinatal mortality of the ECV cohort was 0.12%.
| Outcome | Relative effect (95% CI) | Assumed risk -ECV at term | Corresponding risk - Intervention=ECV commenced before term (95% CI) | Participants (studies) |
|---|---|---|---|---|
| Non-cephalic presentation at the birth | RR 0.81 (0.74 to 0.9) | 517/1000 | 419 /1000(383 to 465) | 1 906(3) |
| Vaginal cephalic birth not achieved (caesarean section + vaginal breech birth) | RR 0.9 (0.83 to 0.97) | 633/1000 | 570 /1000(525 to 614) | 1 888(3) |
| Caesarean section | RR 0.92 (0.85 to 1) | 560/1000 | 515 /1000(476 to 560) | 1 888(3) |
| Vaginal breech birth | RR 0.44 (0.25 to 0.78) | 26/1000 | 11/1000(6 to 20) | 1 888(3) |
Primary/Secondary Keywords