At what age does menstruation typically begin?
Girls start menstruating at the average age of 12. However, girls can begin menstruating as early as 8 years of age or as late as 16 years of age. Women stop menstruating at menopause, which occurs at about the age of 50. At menopause, a woman stops producing eggs (stops ovulating) and can no longer become pregnant, the body stops preparing the uterus for a possibly pregnancy, and the monthly menses stops.
As girls approach their teen years, many changes occur to prepare their bodies for adult life. The body grows taller, forms breasts, and grows hair. Another change prepares the body for pregnancy. Once the body, brain and womb are old enough, a monthly bleeding cycle occurs. The lining of the womb prepares for pregnancy each month. If a pregnancy does not occur, the lining is washed clean with blood. This blood appears from the woman's vagina. This monthly cycle is called menstruation, often referred to as her "period". It usually begins around the age of 12, but can start as early as age 8 or as late as 16. If menstruation does not start by age 16, help is needed. There are tests that can check for normal growth and cycles. If periods stop for 6 months, without a pregnancy, before age 35, a health care provider should be notified. From her first period on, a woman can get pregnant. The ability to get pregnant lasts until periods stop for a year, usually around age 51.