Amenorrhea - primary

Alternative names:

absent menses; absent periods; no periods; primary amenorrhea

Definition:

The absence of any menstrual flow by the age of 16.

Causes, incidence, and risk factors:

The median age for menarche is approximately 12.3 years of age. However, the range varies widely. The incidence of primary amenorrhea in the U.S. is only 2.5%. Primary amenorrhea is not considered to have occurred until a girl is beyond age 16 years without the onset of menses. Primary amenorrhea may occur with or without other signs of puberty.

There are multiple causes for primary amenorrhea:

• normal delay of onset (up to age 14 or 15)
• drastic weight reduction (resulting from poverty, fad dieting, anorexia nervosa, bulimia, or other cause)
• congenital abnormalities of the genital system
• hypoglycemia
• extreme obesity
• gonadal dysgenesis
• Turner's syndrome (XO)
• hypogonadotropic hypogonadism
• testicular feminization syndrome
• true hermaphroditism
• chronic illness
• malnutrition
• Crohn's disease
• cystic fibrosis
• congenital heart disease (cyanotic)
• craniopharyngioma, ovarian tumors, adrenal tumors
• hyperthyroidism
• imperforate hymen, vaginal absence, cervical absence
• adrenogenital syndrome
• Prader-Willi syndrome
• polycystic ovarian disease
• congenital adrenal hypoplasia