Neural tube defects and folic acid supplements.
D005260:Female; D005492:Folic Acid / Q000627:therapeutic use*; D006801:Humans; D009436:Neural Tube Defects / Q000453:epidemiology / Q000517:prevention & control*; D009825:Oklahoma / Q000453:epidemiology; D011159:Population Surveillance; D011247:Pregnancy; D011295:Prenatal Care
D005492:Folic Acid