Does antenatal administration of magnesium to women at risk of preterm delivery improve neurologic outcomes in their infants?

Infants delivered to women who received antenatal magnesium to prevent preterm delivery are slightly less likely to develop cerebral palsy. (LOE = 1a)

Crowther CA, Middleton PF, Voysey M, et al, for the AMICABLE Group. Assessing the neuroprotective benefits for babies of antenatal magnesium sulphate: An individual participant data meta-analysis. PLOS Med 2017;14(10):e1002398.  [PMID:28976987]

Meta-analysis (randomized controlled trials)

Government

Inpatient (any location)

These authors searched several databases and registries to identify randomized trials of antenatal administration of magnesium to women at high risk of preterm delivery. The included trials had to have assessed neurologic outcomes in the infants. Two authors independently assessed the studies for inclusion and assessed the risk of bias in the included studies. Finally, the investigators contacted the original authors and obtained the patient-level data for pooling and analysis. They included 5 completed trials (2 are still under way) and had data on 5493 women and 6131 babies. Overall, they found no improvement in the composite outcome of infant death or cerebral palsy or in the single outcome of infant death. However, in the 4 trials designed specifically to assess neuroprotection, there was a modest reduction in the combined outcome (15% vs 17%; number needed to treat [NNT] = 43) and in cerebral palsy (5% vs 7%; NNT = 48). Maternal complications and outcomes were inconsistently reported in the trials. In the 2 studies that reported maternal complications, the rate of cesarean delivery and other secondary outcomes were comparable in the 2 treatment groups.