Chilling a newborn\'s entire body can help prevent or reduce brain damage caused by lack of oxygen during difficult births, research suggests. However, experts say the results are too preliminary and in conflict with previous research for the treatment to be used outside of medical studies. \"Widespread application of brain cooling ... would be premature,\" Dr. Lu-Ann Papile, a neonatologist at the University of New Mexico Health Sciences Center, wrote in an editorial accompanying the study in Thursday\'s New England Journal of Medicine. She had no role in the study. A pilot study in newborns found no benefit. But the new study was the largest to test the technique. It was led by doctors at Wayne State University in Detroit , involved 15 children\'s hospitals around the country and was funded by the federal government. Newborns were randomly assigned to get usual care or the hypothermia treatment. It involves placing the babies on a special blanket containing chilled water that lowers their temperature to 92.3 degrees for three days, then gradually rewarms them back to normal, around 98.6 degrees. Babies were evaluated 18 to 22 months later.