CORRECTION: Epsom salt can prevent cerebral palsy: U.S.

WASHINGTON (Reuters) - Giving a woman an infusion of Epsom salts when she goes into premature labor can help protect her baby from cerebral palsy, U.S. researchers reported on Thursday.

Magnesium sulfate, popularly known as Epsom salts, cut the rate of cerebral palsy in half, Dr. John Thorp, a professor of obstetrics at the University of North Carolina at Chapel Hill, and colleagues reported.

"We have a cheap, widely available treatment already in hand that cuts in half the risk of babies being born with an extremely disabling disorder," Thorp said in a statement.

"And virtually every delivery room in the United States is already stocked with magnesium sulfate solutions that are given to pregnant women during childbirth for other reasons."

Dr. Alan Fleischman, medical director of the birth defect charity March of Dimes, was more cautious. "I think it is an important study," he said in a telephone interview.

But he noted that more study was needed to understand how the treatment works, and said the children were not protected from more subtle brain damage that affected intellectual and cognitive function.

Thorp's team presented their findings to a meeting of the Society for Maternal-Fetal Medicine in Dallas.

They gave either magnesium sulfate or a placebo to 2,241 women going into early labor or with ruptured membranes. The women's pregnancies were at between 24 to 31 weeks -- a full-term pregnancy goes 40 weeks.

Babies born as prematurely as that can suffer brain damage and other problems including cerebral palsy, a range of conditions that affect control of movement and posture.