Stages of Menopause
There are really only two important stages involved as a woman makes the transition from her reproductive years to her post-reproductive years. The term menopause means the permanent cessation of menstrual periods. Menopause is recognized as having occurred when 12 months have passed since a menstrual period. It is a diagnosis that can be made only in retrospect. When menstrual periods stop, it means that the ovaries no longer produce enough estrogen and progesterone to cause them to occur. Women who have had a hysterectomy do not have the menstrual period as a convenient marker of ovarian function, and this may make it a little bit more difficult to determine when menopause has occurred. While there is no laboratory test that can predict when menopause will occur, testing the FSH (follicle-stimulating hormone) level in the bloodstream can help these women determine whether or not they are truly postmenopausal. Usually, we consider menopause to have occurred when several FSH levels taken a few months apart are consistently elevated.
Perimenopause begins when a woman first notices significant variability in the length of her menstrual cycles (the number of days between menstrual periods) and ends when one full year has elapsed since her last menstrual period. Perimenopause can last for several years. This is the time when women begin to have symptoms that are due to estrogen withdrawal as the ovaries slowly begin to produce less and less estrogen and progesterone. The ovaries don’t just wind down in an orderly fashion, however. During this time, there are erratic and unpredictable changes in hormone levels as the ovaries produce ovarian follicles (eggs) of variable quality. Some periods can be quite heavy; others quite light. Periods can be closer together or farther apart. There will be times when a woman will have symptoms of estrogen deficiency (hot flashes, night sweats, vaginal dryness) and other times when she will seem to have an excess of estrogen (weight gain, bloating, breast tenderness, heavy periods). The unpredictable nature of the hormonal swings can make this stage the most difficult to deal with.
After a full year has passed since the final menstrual period, a woman has then entered the postmenopausal phase of her life. Due to the increased life expectancy of women that has come about in the last hundred years, most women can be expected to live at least one third of their lives in the postmenopausal phase. During this phase, women may have symptoms that are due to estrogen deficiency rather than to estrogen withdrawal. The hot flashes and night sweats typical of the perimenopausal phase resolve to a large extent for most (but not all) women by the beginning of the postmenopausal phase, and are frequently replaced by chronic vaginal dryness as the predominating symptom. During this phase, the estrogen-deficiency conditions of osteopenia and osteoporosis are often diagnosed.
I prefer to use the term menopausal transition rather than perimenopause when discussing the changes that occur during this phase of a woman’s life. Menopausal transition is a more accurate term, and it emphasizes that the significant changes that are occurring are a work in progress and that they will come to an end at some point, with each woman reaching a new hormonal equilibrium. The menopause transition is a time for reflection, reassessment, and setting goals that will help to ensure a long and healthy life after menopause.