The U.S. Food and Drug Administration recommends that pregnant women, women of childbearing age, and young children avoid eating shark, swordfish, mackerel, and tilefish. These fish often harbor high levels of methylmercury, a potent human neurotoxin. Methylmercury readily crosses the placenta and has the potential to significantly damage the fetal nervous system. Health care providers are responsible for educating women about the hazards of methylmercury and the Food and Drug Administration recommendation.