title: Vitamin supplements to prevent neural tube defects.
mesh_terms: D002986:Clinical Trials as Topic; D035061:Control Groups; D004311:Double-Blind Method; D005260:Female; D005527:Food, Fortified; D006801:Humans; D008431:Maternal-Fetal Exchange; D009436:Neural Tube Defects / Q000517:prevention & control*; D011247:Pregnancy; D011897:Random Allocation; D014815:Vitamins / Q000008:administration & dosage*
chemical_list: D014815:Vitamins