Tocolysis for repeat external cephalic version in breech presentation at term: a randomised, double-blinded, placebo-controlled trial.

BACKGROUND

External cephalic version (ECV) reduces the incidence of breech presentation at term and caesarean section for non-cephalic births. Tocolytics may improve success rates, but are time consuming, may cause side effects and have not been proven to alter caesarean section rates. The aim of this trial was to determine whether tocolysis should be used if ECV is being re-attempted after a failed attempt.

OBJECTIVE

To determine whether tocolysis should be used if ECV is being re-attempted after a failed attempt.

DESIGN

Randomised, double-blinded, placebo-controlled trial.

SETTING

UK teaching hospital.

POPULATION

One hundred and twenty-four women with a breech presentation at term who had undergone an unsuccessful attempt at ECV.

METHODS

Relative risks with 95% confidence intervals for categorical variables and a t test for continuous variables. Analysis was by intention to treat.

MAIN OUTCOME MEASURES

Incidence of cephalic presentation at delivery. Secondary outcomes were caesarean section and measures of neonatal and maternal morbidity.

RESULTS

The use of tocolysis for a repeat attempt at ECV significantly increases the incidence of cephalic presentation at delivery (RR 3.21; 95% CI 1.23-8.39) and reduces the incidence of caesarean section (RR 0.33; 95% CI 0.14-0.80). The effects were most marked in multiparous women (RR for cephalic presentation at delivery 9.38; 95% CI 1.64-53.62). Maternal and neonatal morbidity remain unchanged.

CONCLUSIONS

The use of tocolysis increases the success rate of repeat ECV and reduces the incidence of caesarean section. A policy of only using tocolysis where an initial attempt has failed leads to a relatively high success rate with minimum usage of tocolysis.