Effect of magnesium sulfate given for neuroprotection before preterm birth: a randomized controlled trial.
BACKGROUND
Prenatal magnesium sulfate may reduce the risk of cerebral palsy or death in very preterm infants.


OBJECTIVE
To determine the effectiveness of magnesium sulfate given for neuroprotection to women at risk of preterm birth before 30 weeks' gestation in preventing pediatric mortality and cerebral palsy.


METHODS
Randomized controlled trial at 16 tertiary hospitals in Australia and New Zealand with stratification by center and multiple pregnancy. A total of 1062 women with fetuses younger than 30 weeks' gestation for whom birth was planned or expected within 24 hours were enrolled from February 1996 to September 2000 with follow-up of surviving children at a corrected age of 2 years.


METHODS
Women were randomly assigned to receive a loading infusion of 8 mL (4 g [16 mmol] of 0.5 g/mL of magnesium sulfate solution or isotonic sodium chloride solution [0.9%]) for 20 minutes followed by a maintenance infusion of 2 mL/h for up to 24 hours.


METHODS
Rates of total pediatric mortality, cerebral palsy, and the combined outcome of death or cerebral palsy at a corrected age of 2 years.


RESULTS
Data were analyzed for 1047 (99%) 2-year survivors. Total pediatric mortality (13.8% vs 17.1%; relative risk [RR], 0.83; 95% confidence interval [CI], 0.64-1.09), cerebral palsy in survivors (6.8% vs 8.2%; RR, 0.83; 95% CI, 0.54-1.27), and combined death or cerebral palsy (19.8% vs 24.0%; RR, 0.83; 95% CI, 0.66-1.03) were less frequent for infants exposed to magnesium sulfate, but none of the differences were statistically significant. Substantial gross motor dysfunction (3.4% vs 6.6%; RR, 0.51; 95% CI, 0.29-0.91) and combined death or substantial gross motor dysfunction (17.0% vs 22.7%; RR, 0.75; 95% CI, 0.59-0.96) were significantly reduced in the magnesium group.


CONCLUSIONS
Magnesium sulfate given to women immediately before very preterm birth may improve important pediatric outcomes. No serious harmful effects were seen.
Crowther
Caroline A
CA
Department of Obstetrics and Gynaecology, The University of Adelaide, Women's and Children's Hospital, King William Road, North Adelaide, South Australia, 5006 Australia. caroline.crowther@adelaide.edu.au
Hiller
Janet E
JE
Doyle
Lex W
LW
Haslam
Ross R
RR
D002547:Cerebral Palsy / Q000517:prevention & control*; D002658:Developmental Disabilities / Q000517:prevention & control; D005260:Female; D006801:Humans; D007223:Infant; D007226:Infant Mortality; D007231:Infant, Newborn; D007234:Infant, Premature; D007235:Infant, Premature, Diseases / Q000517:prevention & control*; D008278:Magnesium Sulfate / Q000008:administration & dosage / Q000627:therapeutic use*; D018696:Neuroprotective Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D007752:Obstetric Labor, Premature; D011247:Pregnancy; D011256:Pregnancy Outcome; D018566:Pregnancy, High-Risk
D018696:Neuroprotective Agents; D008278:Magnesium Sulfate