Vitamins More Vital Than Ever

Already known to cut the risk of neural-tube defects by half, prenatal vitamins also lower the risks of many other problems.

Already known to cut the risk of neural-tube defects by half, prenatal vitamins also lower the risk for heart defects by 39 percent, limb deformities by 47 percent, cleft palate by 58 percent, and hydrocephalus (the accumulation of fluid on the brain) by 63 percent, according to an analysis of 41 studies by Gideon Koren, M.D., a professor of pediatrics at the University of Toronto. Prenatal vitamins contain more iron and folic acid than standard multivitamins, and Koren recommends taking them as soon as you start to plan a family.