Effect of Magnesium Sulfate Administration for Neuroprotection on Latency in Women with Preterm Premature Rupture of Membranes

ObjectiveThis study aims to evaluate whether magnesium sulfate administration for neuroprotection prolongs latency in women with preterm premature rupture of membranes (PPROM) between 24 and 31(6/7) weeks' gestation. Study DesignThis is a secondary analysis of a randomized controlled trial of magnesium sulfate for prevention of cerebral palsy. Gravid women with a singleton pregnancy between 24 and 31(6/7) weeks' gestation with PPROM without evidence of labor were randomized to receive magnesium sulfate, administered intravenously as a 6-g bolus followed by a constant infusion of 2g per hour up to 12 hours, or placebo. Maternal outcomes for this analysis were delivery in less than 48 hours and in less than 7 days from randomization. Neonatal outcomes included a composite of respiratory distress syndrome, interventricular hemorrhage grades 3 or 4, periventricular leukomalacia, sepsis, necrotizing enterocolitis, retinopathy of prematurity, or death. ResultsA total of 1,259 women were included. The rate of delivery<48 hours was not different in the magnesium sulfate and the placebo groups (22.2 and 20.7%, p=0.51). Delivery<7 days was similar between groups (55.4 and 51.4%, p=0.16). Median latency was also similar between groups (median [interquartile range], 6.0 days [range, 2.4-13.8 days] and 6.6 days [range, 2.4-15.1 days], p=0.29). Composite neonatal outcomes did not differ between groups. ConclusionMagnesium sulfate administration given for neuroprotection in women with a singleton gestation with PPROM and without labor before 32 weeks does not impact latency.