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amenorrhea in which the menses have never occurred.
primary amenorrheaGynecology The absence of any menstrual flow by age 16, which affects 2.5% in US; median age for menarche is ± age 12.3; PA may occur with or without other signs of puberty Etiology Normal delay of menarche; drastic weight loss–poverty, fad dieting, anorexia nervosa, bulimia, etc; congenital defects of genital system, hypoglycemia, extreme obesity, gonadal dysgenesis, Turner/XO syndrome, hypogonadotropic hypogonadism, testicular feminization, true hermaphroditism, chronic illness, malnutrition, Crohn's disease, cystic fibrosis, cyanotic congenital heart disease, craniopharyngioma, ovarian tumors, adrenal tumors, hyperthyroidism, imperforate hymen, vaginal and/or cervical absence, adrenogenital syndrome, Prader-Willi syndrome, polycystic ovarian disease, congenital adrenal hypoplasia. See Amenorrhea.
pri·mar·y a·men·or·rhe·a(prī'mar-ē ā-men'ŏr-ē'ă)
Amenorrhea in which menses have never occurred.