Letter: Oral contraceptives and vitamin requirements.
D001361:Avitaminosis / Q000139:chemically induced* / Q000517:prevention & control; D003276:Contraceptives, Oral / Q000009:adverse effects*; D005260:Female; D006801:Humans; D009751:Nutritional Requirements; D014815:Vitamins / Q000008:administration & dosage
D003276:Contraceptives, Oral; D014815:Vitamins