For years, mothers-to-be with rising blood pressure and a life-threatening condition called eclampsia have been given hefty doses of magnesium to prevent convulsions in late pregnancy - despite scant scientific proof that it works.
Now, a study published in the New England Journal shows that magnesium sulfate protects pregnant women very well, in fact better than an anti-convulsive drug called phenytoin. Other evidence suggests it may be good for babies, too.In a randomized trial, Dr. Michael J. Lucas and his team from the University of Texas Southwestern Medical Center in Dallas found that none of 1,049 women given magnesium sulfate had convulsions, while 10 of 1,089 women given phenytoin did.
These findings "convincingly demonstrate" that magnesium is superior to phenytoin, noted Dr. James M. Roberts, an obstetrician and director of the Magee-Women's Research Institute in Pittsburgh, in a journal editorial.
On the basis of this and a similar study, Roberts added in a telephone interview, it is clear that magnesium does no harm to babies. In fact, one study suggests that if mothers are given magnesium to prevent seizures or stop early labor, premature babies have a lower risk of cerebral palsy.
Though 1 in every 1,000 pregnant women has seizures, it is too soon to recommend magnesium for all women at risk of eclampsia. But obstetricians who have long held a "religious" faith in magnesium can now feel vindicated, he says.
- Judy Foreman