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About Amenorrhea

Amenorrhea is the absence of a menstrual period.

Amenorrhea is sometimes categorized as:

  • Primary amenorrhea. This describes a young woman who has not had a period by age 16.
  • Secondary amenorrhea. This occurs when a woman who once had regular periods experiences an absence of more than three cycles. Causes of secondary amenorrhea include pregnancy.

Having regular periods is an important sign of overall health. Missing a period, when not caused by pregnancy, breastfeeding, or menopause, is generally a sign of another health problem. If you miss your period, talk to your health care provider about possible causes, including pregnancy.