"The new Canadian study, the first to combine the results of the best studies on prenatal vitamins and rates of pediatric cancers, suggests expectant mothers who take folic acid-fortified prenatal vitamins before and during the first three months of pregnancy lower the risk their babies will develop leukemia, brain tumours and neuroblastoma by as much as 47 per cent."
http://www.canada.com/ottawacitizen/...3-25b2c1695a9d