Menopause Health Article

Natural (spontaneous) menopause

Most menopause is natural and occurs as part of the aging cycle for women. Technically, it refers to a state in a woman's menstrual cycle which happens a year from the date of her last menstrual period. Indications that the process is starting may occur in a woman's 40's with the lengthening and irregularity of menstrual cycles. The process can take as long as eight years, or may be over in two. Only 10% of women report that menstruation ceases suddenly, with no cycle irregularity prior.

There are four stages that a woman experiences when she experiences natural menopause.

MENSTRUATION. When a woman enters puberty, each month her body releases one of the more than 400,000 eggs that are stored in her ovaries, and the lining of the womb (uterus) thickens in anticipation of receiving a fertilized egg. If the egg is not fertilized, progesterone levels drop and the uterine lining sheds. This is a normal menstrual cycle.

By the time a woman reaches her late 30s or 40s, her ovaries begin to produce less estrogen and progesterone, releasing eggs less often. The gradual decline of estrogen causes a wide variety of changes in tissues that respond to estrogen—including the vagina, vulva, uterus, bladder, urethra, breasts, bones, heart, blood vessels, brain, skin, hair, and mucous membranes.

As the levels of hormones fluctuate, the menstrual cycle begins to change. Some women may have longer periods with heavy flow followed by shorter cycles and hardly any bleeding, beginning as much as two to eight years before menopause. Others will begin to miss periods completely. During this time, a woman also becomes less able to get pregnant (although contraception should be continued until the postmenopausal state is established). This is the stage of premenopause which represents the very beginning of the process. Typically, it begins when a woman is in her mid-to-late forties.

PERIMENOPAUSAL TRANSITION. Perimenopause is the stage most women consider as going through menopause. Here a woman's cycles become very erratic. She may experience more hot flashes and other symptoms. Only about 15% of women report severe symptoms. This stage lasts about four years, the two years prior to the last cycle and the two years following it. For 95% of women, the age of onset ranges from 39 to 51 years. The average age for perimenopause is 47.5 years, with completion at 51.

MENOPAUSE. This is the permanent cessation of menstruation following the loss of ovarian activity. It often is not officially noted until a year with no cycles has passed.

POSTMENOPAUSE. This stage represents the last years of a woman's life. She may well spend a third to half of her life in this stage. During the first years after menopause, a woman may still experience some perimenopausal symptoms. Here, a woman will begin to deal with some of the effects of aging. In 2001, a woman at 50 or 51 may truly be at mid-life, according to the calendar, since many women will live to be a hundred.