Amenorrhea (uh-men-o-REE-uh) is the absence of menstruation one or more missed menstrual periods. Women who have missed at least three menstrual periods in a row have amenorrhea, as do girls who haven't begun menstruation by age 15. The most common cause of amenorrhea is pregnancy. It is not a disease, and it does not mean that a for it to stop during breastfeeding, to a person is infertile, but it can be a sign of a health problem that needs some attention. Around puberty, menstruation begins, and then it normally occurs about once a month until the age of 50 years. At this time, periods stop altogether, as menopause begins. During pregnancy, menstruation also stops, and it is common