Since the very earliest sign of perimenopause is often a change in the regularity of your menstrual cycle, it's a good place to start on the list of physical menopausal changes. You may be one of those women who notice a change not only in the timing of your period, but also in the amount of flow. Sometimes heavier periods become so over several months or years, until one day you realize that your life revolves around having pads and tampons in every purse and coat pocket, and you begin to plan your vacations and activities around that time of the month. That is, if you can predict that time of the month.
What's Going On?
What causes cycle irregularity during perimenopause? Once again, the culprit behind the majority of irregular periods is hormonal fluctuations. In fact, hormone fluctuations can cause a variety of irregularities in your periods. As you enter perimenopause, you probably ovulate less frequently. Because all hormone releases are triggered by others, an unusual fluctuation in one hormone can set off a series of unusual fluctuations in others, as your body tries to spur on or hold back the hormone in flux. For that reason, you might have a six-week cycle, followed by a four-week cycle, followed by a six-week cycle with unusually light flow, and so on. (A cycle is the length of time from the first day of one menstrual period to the first day of the next.) Your body is going through a series of starts and stalls as it attempts to adjust to fluctuating levels of hormones in your bloodstream.
Because you ovulate less frequently during this time, your body's estrogen levels often are unchecked by progesterone. As a result, your uterine lining can develop abnormal cell changes that lead to unusually heavy bleeding or midcycle spotting.
A common cause of abnormal bleeding is a precancerous condition of the lining of the uterus called endometrial hyperplasia. This excessive growth of the uterine lining can result from having unbalanced estrogen. If diagnosed when still in its early stages, it can be treated medically. Untreated endometrial hyperplasia can develop into endometrial cancer. It's a good idea to report any changes in bleeding patterns to your health care provider.