234 Magnesium Sulphate Given for Neuroprotection Before Preterm Birth

Abstract

Background: In some human observational studies, magnesium sulphate (MgSO4) is associated with a significant reduction of pediatric mortality and cerebral palsy. Aim: To assess if prenatal MgSO4 given to women in labor before 33 weeks'gestation is neuroprotective for the infant. Methods: 564 consenting women in 13 french centers whose birth was planned or expected within 24 hours were randomised to receive a sole dose of 4 g of MgSO4 or 4 g of isotonic sodium chloride solution for 30 minutes. In 660 out of 688 very preterm newborns who had at least one cranial ultrasonographic study (US), the primary outcome measures were the rates of mortality up to discharge of hospital, of the severe white matter injury (WMI) (defined by the presence of cavitations and/or intraparenchymal haemorrhage) and the combined of death and severe WMI. The secondary outcome measures were the rates of WMI (defined by severe WMI or persisting hyperechogenicities at two US more than 14 days and/or isolated ventricular dilatation), and of non-parenchymal haemorrhages. Results: Mortality up to discharge (9.4% vs 10.5%; RR 0.85, 95% CI 0.56 − 1.28), severe WMI (9.7% vs 11.8%; RR 0.74, 95% CI 0.47 − 1.14), combined death and severe WMI (16.3% vs 18.0%; RR 0.85, 95% CI 0.63–1.15) were not significantly different between both groups. In the MgSO4 group, significant increases in the rates of preterm rupture of membrane more than 18 hours (p = 0.077) and of materno-fetal infection (p = 0.025) were observed. No women had life threatening events due to magnesium infusion; moderate or mild side effects were reported in 16.6 % of women given MgSO4 and in 1% of women given placebo. No severe side effect was reported in infant. Conclusion: In this trial, even if there is a trend towards a beneficial effect of magnesium, no significant differences were observed between both groups. Financial support : Grants of the French ministry of Health and of the Centre Hospitalier Universitaire of Rouen 1997; Study approved by the ethical comittee of Haute-Normandie, France.