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.

Neonatal effects of nifedipine and ritodrine for preterm labor.

OBJECTIVE: We compared nifedipine and ritodrine for treatment of preterm labor with respect to neonatal outcome. METHODS: We conducted an open randomized multicenter study of neonatal outcome in 185 women who received either oral nifedipine (n = 95) or intravenous (IV) ritodrine (n = 90) for treatment of preterm labor. Secondary outcome measures included neonatal mortality and morbidity, especially neonatal intensive care unit (NICU) admission, respiratory distress syndrome (RDS), and intracranial bleeding. RESULTS: There were no significant differences in umbilical artery pH values and Apgar scores between groups. Nifedipine was associated with lower admission rates to the NICU (49% versus 66%; odds ratio 0. 51, confidence interval 0.28, 0.93) compared with ritodrine, and lower incidences of RDS (21% versus 37%; 0.46, 0.24, 0.89), intracranial bleeding (18% versus 31%; 0.48, 0.24, 0.96), and neonatal jaundice (52% versus 67%; 0.53, 0.29, 0.97). Logistic regression analysis showed that even after correction for gestational age at birth, newborn risk of RDS, intracranial bleeding, or neonatal jaundice was significantly lower in the nifedipine group than the ritodrine group. CONCLUSION: Nifedipine for treatment of preterm labor was associated with a lower incidence of neonatal morbidity than ritodrine. That difference appeared to be partly because of the higher tocolytic efficacy of nifedipine and partly because of an intrinsic beneficial effect of nifedipine, or the lack of harmful effects when compared with ritodrine.