Maintenance tocolysis with nifedipine in threatened preterm labour: 2-year follow up of the offspring in the APOSTEL II trial

Objective: To evaluate long-term effects of maintenance tocolysis with nifedipine on neurodevelopmental outcome of the infant. Design, Setting and Population: Follow up of infants of women who participated in a multicentre randomised controlled trial on maintenance tocolysis with nifedipine versus placebo. Methods: Two years after the APOSTEL II trial on maintenance tocolysis with nifedipine versus placebo, we asked participants to complete the Ages and Stages Questionnaire. Main outcome measures: Infant development was measured in five domains. Developmental delay was defined as a score of ≤1 SD in one or more developmental domains. We performed exploratory subgroup analysis in women with preterm prolonged rupture of the membranes, and in women with a cervical length <10 mm at study entry. Results: Of the 276 women eligible for follow up, 135 (52.5%) returned the questionnaire, encompassing data of 170 infants. At 2 years of age, infants of women with nifedipine maintenance tocolysis compared with placebo had a higher overall incidence of fine motor problems (22.2 versus 7.6%, OR 3.43, 95% CI 1.29–9.14, P = 0.01), and a lower incidence of poor problem-solving (21.1 versus 29.1%, OR 0.27, 95% CI 0.08-0.95, P = 0.04). Conclusions: This follow-up study revealed no clear benefit of nifedipine maintenance tocolysis at 2 years of age. As short-term adverse perinatal outcome was not reduced in the original APOSTEL II trial, we conclude that maintenance tocolysis does not appear to be beneficial at this time. Tweetable abstract: No clear benefit of nifedipine maintenance tocolysis in preterm labour on 2-year infant outcome.