Perimenopause refers to the years preceding menopause (peri = “around”). Roughly coinciding with ages 35-52, this transition period from reproductive life to post reproductive life is caused by a change in the way the ovaries produce their hormones which leads to menstrual cycle changes.
The ovary of a reproductive aged woman, under the pituitary gland’s control, begins to develop six or seven “eggs” for ovulation around the second day of a menstrual period. These are surrounded by hormone producing cells called “follicles” – small cysts. One of these will produce “inhibin,” a hormone which shuts down the other eggs and they die off. This “dominant” follicle releases estrogen, which grows the tissue that lines the uterus. After the egg is released with ovulation, the cells also make progesterone, which keeps the uterine lining from shedding. If no pregnancy occurs, these follicle cells die and progesterone production stops. The presence – followed by the absence – of progesterone is the event which must occur for the uterus to completely discharge all its tissue as a period. A woman with regular periods is one who has ovaries that operate this way every month.
In the perimenopause, the ovary can’t produce progesterone every month. Ovulation, and with it, progesterone release, occurs only intermittently. This is due to the fact that inhibin production is lower. When the group of eggs begins to grow, none of them becomes dominant to shut the others down. So these follicles dump a bunch of estrogen into the bloodstream to grow a lush uterine lining. Ovulation doesn’t occur, and there is no progesterone. The uterine lining keeps growing until it outgrows its blood supply and then starts to bleed from its surface. The uterus can’t completely shed all the lining and this results in very irregular periods with inconsistent amounts of blood loss.
As a woman enters her mid-thirties, she may notice a shorter time between periods – 21 to 23 days instead of the usual 28. Variation in cycle length and in amount of bleeding may begin to occur. With multiple follicles producing more estrogen than usual and no progesterone, the uterine lining can grow thick and shaggy, resulting in crazy bleeding for days at a time. As time progresses, the amount of daily estrogen is inconsistently produced. One may then begin to experience “hot flashes” – intense heat radiating from the upper body for about 10 minutes followed by lots of sweating and then the sensation of freezing to death. Since this most often occurs at night, all stages of sleep are compromised. This may result in significant mood disturbances, impaired job or task performance, and a marked loss of well-being for many.
Every woman is different. Some women are fortunate and have none of these problems. Some women are incapacitated. Most women fall somewhere in the middle of these extremes.
Obviously, not everyone needs treatment, but of course it is available. The goals of treatment include decreasing anemia and fatigue from dysfunctional bleeding, improving sleep and minimizing hot flashes, and promoting a sense of control and well-being. Most treatments involve either brief or more prolonged courses of hormonal therapy. Since pregnancy often occurs in perimenopause, cyclic birth control pills often treat all of these symptoms while providing contraception if it’s desired. These work by suppressing the ovaries and creating cyclic estrogen and progesterone levels. In essence, they create a hormonal balance.
Other modes of hormonal therapy are available. Progesterone uterine implants (the Mirena IUD’s) can often stop heavy periods. Some women opt for uterine ablation, a heat treatment applied to the uterine cavity to permanently destroy the uterine lining so that it cannot regrow. Short courses of antidepressants are wonderful for improving sleep and mood swings and also combatting fatigue. Some women with less severe symptoms often improve with increased exercise and vitamin supplements. The key is in individualization of treatment plans to find the best treatment plan for each symptomatic woman entering this phase of life.