Heavy bleeding, emotional ups and downs, night sweats, irregular periods–these are symptoms familiar to women in their middle years. Signals of perimenopause, they usually begin in the 40s, then wax and wane until a woman reaches menopause.

The mean age of menopause–defined, as one year without a menstrual cycle–is 51. Perimenopause, the time leading up to menopause, can last from two to eight years, depending on the woman.

Perimenopause is often a time of conflicting emotional and physical changes: some may grieve the end of the childbearing years; others may rejoice at the thought that pregnancy is no longer an issue. Some women face a mid-life crisis as they make the transition from a more youthful self-image to the realization that they are looking at middle age in the mirror.

The physical changes that accompany perimenopause are largely a result of the gradual shutting down of the ovaries. Hormone levels become erratic and unpredictable, leading to abnormal bleeding and irregular menstrual cycles.

Changes in the menstrual cycle are one of the early signs. Some women first notice irregular spotting; others will miss several periods, then return to a normal pattern.

As estrogen production decreases, the pituitary increases its production of follicle stimulating hormone (FSH) to stimulate the ovaries to produce more estrogen. In early perimenopause this tends to make cycles shorter, from 21 to 24 days. With shorter cycles, periods come more often, and women suffering from PMS get more frequent symptoms.

Later in perimenopause, cycles become more unpredictable. For some women menstrual flow may be lighter, for others it may be more frequent and very heavy.

Approximately one of every five visits to a gynecologist’s office involves concerns over abnormal uterine bleeding. When it’s been determined that the abnormal bleeding is related to hormonal changes associated with perimenopause, oral contraceptives or progestins may be prescribed.

Unstable hormone levels can lead to enlargement of fibroid tumors at this time of life. Although they are benign, fibroids can contribute to excessive bleeding. In most cases fibroids tend to shrink after menopause.

Hot flashes, night sweats and sleep problems, commonly associated with menopause, often begin in the perimenopausal years. As estrogen levels decline, hot flashes and night sweats–known as vasomotor symptoms–tend to increase.

Many women have trouble going to sleep or getting back to sleep when awakened by night sweats. One study found that one of every four women who were still menstruating reported vasomotor symptoms before she skipped one or several periods.

Estrogen replacement is the most effective remedy for vasomotor symptoms, but since the results of the Women’s Health Initiative revealed the risks associated with hormone replacement, women and their physicians have been reluctant to choose this option.

Genitourinary changes may begin to show up in the perimenopausal years. The vagina, bladder and urethra are all sensitive to the effects of estrogen. As estrogen levels fall, tissues become thinner and drier. Women may notice pain with intercourse and may be more prone to bladder infections and vaginal yeast infections.

Migraine headaches: Erratic hormonal shifts in the perimenopausal years can increase the frequency and severity of migraines in women with a history of migraine and mark the beginning of migraines for some women who had never had a problem with them before. Some women report that their migraines improve with the onset of menopause, however.

Weight gain is common as women approach menopause, in part because of slowing metabolism related to aging. But weight gain is not inevitable in the middle years. Making small changes in diet to cut back on calories and making an effort to exercise more can help.

Psychological changes may stem from fears related to aging. The combination of mood changes and physically distressing symptoms such as irregular bleeding, hot flashes and sleep disturbances can create a negative attitude toward menopause and the uncertainties of middle age.

Perimenopause is a time of transition. Some of the symptoms such as hot flahes and sleep disturbances may continue for a time into menopause. Other symptoms, such as irregular bleeding, PMS and, for some, migraines will end. By maintaining a positive attitude, practicing self help strategies and seeking support from friends, family and a caring health care provider, a woman can power through this new life phase.

Michelle Herbert, PharmD, CDE—Rev. 5/19/2010 TNK