Folic acid and the pill.
D000328:Adult; D000748:Anemia, Macrocytic / Q000139:chemically induced*; D003276:Contraceptives, Oral / Q000009:adverse effects*; D004997:Ethinyl Estradiol / Q000009:adverse effects; D005260:Female; D005494:Folic Acid Deficiency / Q000139:chemically induced*; D006801:Humans; D008875:Middle Aged; D009640:Norethindrone / Q000009:adverse effects
D003276:Contraceptives, Oral; D004997:Ethinyl Estradiol; D009640:Norethindrone