The relation between breast-feeding and amenorrhea: report of a survey.
D000568:Amenorrhea / Q000209:etiology*; D001942:Breast Feeding; D005193:Family Planning Services; D005260:Female; D006801:Humans; D007223:Infant; D007224:Infant Care; D007225:Infant Food; D011247:Pregnancy; D013997:Time Factors