Interventions to help external cephalic version for breech presentation at term

Abstract

Background: Breech presentation places a fetus at increased risk. The outcome for the baby is improved by planned caesarean section compared with planned vaginal delivery. External cephalic version attempts to reduce the chances of breech presentation at birth, but is not always successful. Tocolytic drugs to relax the uterus as well as other methods have been used in an attempt to facilitate external cephalic version at term.

Objectives: To assess the effects of routine tocolysis, fetal acoustic stimulation, epidural or spinal analgesia and transabdominal amnioinfusion for external cephalic version at term on successful version and measures of pregnancy outcome.

Search strategy: The Cochrane Pregnancy and Childbirth Group trials register (September 2003) and the Cochrane Central Register of Controlled Trials (The Cochrane Library, Issue 3, 2003) were searched.

Selection criteria: Randomised and quasi-randomised trials comparing routine versus selective or no tocolysis; fetal acoustic stimulation in midline fetal spine positions versus dummy or no stimulation; epidural or spinal analgesia versus no regional analgesia; or transabdominal amnioinfusion versus no amnioinfusion for external cephalic version at term.

Data collection and analysis: The reviewer assessed eligibility and trial quality.

Main results: In six trials, routine tocolysis with beta-stimulants was associated with fewer failures of external cephalic version (relative risk (RR) 0.74, 95% confidence interval (CI) 0.64 to 0.87). The reduction in non-cephalic presentations at birth was not statistically significant. Caesarean sections were reduced (RR 0.85, 95% CI 0.72 to 0.99). In four small trials, sublingual nitroglycerine used as a tocolytic was associated with significant side-effects, and was not found to be effective. Fetal acoustic stimulation in midline fetal spine positions was associated with fewer failures of external cephalic version at term (RR 0.17, 95% CI 0.05 to 0.60). With epidural or spinal analgesia, external cephalic version failure, non-cephalic births and caesarean sections were reduced in two trials but not the other. The overall differences were not statistically significant. No randomised trials of transabdominal amnioinfusion for external cephalic version at term were located.

Reviewer's conclusions: Routine tocolysis appears to reduce the failure rate of external cephalic version at term. There is not enough evidence to evaluate the use of fetal acoustic stimulation in midline fetal spine positions, nor of epidural or spinal analgesia. Large volume intravenous preloading may have contributed to the effectiveness demonstrated in two of the latter trials.