Amenorrhea means a woman is not menstruating. A female who has not had her first period by age 16 has primary amenorrhea. This should be distinguished from infrequent or light menstrual cycles (oligomenorrhea), which are very common and usually normal in teenagers, particularly in the first couple of years after menses begin, a time called menarche. If a woman starts her periods, but then stops having periods for at least 3 cycles (90 days), she is said to have secondary amenorrhea.
Imperforate hymen (the opening to the vagina is covered by skin)
Cervical stenosis (the cervix is closed)
Eating disorders: sudden weight reduction, obesity, anorexia nervosa, fad dieting
Chronic disease, e.g., diabetes, anemia, congenital heart disease, thyroid disease
Pituitary or hypothalamic failure
Chromosomal anomaly, e.g., Turner's syndrome
Congenital adrenal hyperplasia
Absence or abnormality of one or more of the female reproductive organs
Physical examination including pelvic and bimanual examination
Laboratory tests for levels of luteinizing hormone, follicle-stimulating hormone, thyroid hormone, prolactin, etc.
Varies, depending on the cause, and may include:
Hormonal replacement therapy and/or other medications
Surgery minor and/or major
Long-term follow-up by an internist or other medical specialist