The effect of indomethacin tocolysis in preterm labour on perinatal outcome: a randomised placebo-controlled trial

Objective To determine whether indomethacin tocolysis in preterm labour is associated with a better perinatal outcome than placebo. Design A randomised placebo-controlled trial. Setting Two university teaching hospitals with level three neonatal intensive care units. Population Women in preterm labour with intact membranes between 23 and 30 weeks of gestation. Methods Random allocation to tocolysis with indomethacin (50 mg followed by 25 mg 6 hourly for 48 hours) or placebo in a double-blind fashion. Main outcome measures The primary outcome, perinatal mortality or severe neonatal morbidity, was defined as perinatal death, necrotising enterocolitis, bronchopulmonary dysplasia, intraventricular haemorrhage or peri-ventricular leucomalacia. Data were analysed using odds ratios (OR) and 95% confidence intervals (95% CI). Results Between March 1995 and February 1996, 34 women (39 babies) were recruited. The baseline characteristics of the two groups were similar. No patient was lost to follow up. In the indomethacin group, gestation was prolonged by > 48 hours in 13/16 (81%) of women vs 10/18 (56%) in the placebo group. The incidence of perinatal mortality or severe neonatal morbidity was not significantly different between the groups, but occurred in twice as many babies in the indomethacin group as in the placebo group-6/19 (32%) vs 3/20 (15%) OR (95% CI) 2.62 (0.44-18.8). There was one perinatal death, of a baby delivered at 24 weeks of gestation. This occurred in the indomethacin group. Conclusion There is no evidence that indomethacin tocolysis is beneficial, and further trials are needed to assess the impact of indomethacin tocolysis in preterm labour.