Menopause
Most women will spend a significant portion of their life in menopause. The average age of menopause is about 51, but it wasn't until the year 1900 that we even lived that long, on average. Thus, in all of human history, menopause is a relatively new life stage. Most women simply did not live long enough to reach it, and those that did, did not spend much time in it. Currently, the average lifespan for a women in the United States is 81. Given this, a modern woman will spend nearly 40% of her life in menopause, and this percentage will only increase as lifespan increases. Moreover, the number of people in menopause will increase as the population ages. Menopause is an important life stage for our whole society. For a blog post on this subject, check HERE.
Many believe menopause is a time when women can focus on themselves and their own productivity instead of the raising of children. Some people feel that women who have reached this stage of life are a great source of relatively untapped human potential because of their cumulative life experience.
Menopause is simply the time when the ovaries cease to function.
Ovaries produce eggs and hormones. The monthly production of eggs is called ovulation. The monthly cyclic production of hormones by the ovaries affects many parts of the body including the endometrium, or lining of the uterus, so that a pregnancy can implant there.
To best understand menopause, please review Menstrual cycle 101 HERE.
As you will see in Menstrual Cycle 101, it is the production of eggs in follicles (eggs cases) that drives the secretion of hormones. Here's how. During the reproductive years, the brain send the chemical messenger FSH ( follicle stimulating hormone) into circulation. When it reaches the ovary, the follicles are stimulated to swell and ripen. During this same time the rest of the ovary secretes high levels of estrogen which serves to thicken the lining of the uterus ( endometrium) in preparation for a possible fertilized egg. After a variable length of time usually about 14 days from the last period, the eggs burst out of the follicle (ovulates ) and is either fertilized by sperm or not. After ovulation, the empty follicle which ovulated changes and begins to secrete large amounts of progesterone, which compacts and dries up the lining of the uterus, so it can slough off so the whole cycle can start over.
What happens in menopause?
Remember that the whole reproductive cycle is cued by the ripening of the follicles and the resultant secretion of hormones. Consider that the ovary is initially full of thousands of unripe follicles of varying sensitivity. Early in our reproductive life, the follicles which are the most sensitive will ovulate first. By the time we are near menopause, we are left with increasingly less sensitive follicles, the "duds" as it were . Eventually none are able to ovulate. They are " too pooped to pop". Without ovulation, hormone production dwindles away over the span of a couple years.
Without follicle ripening, we cannot become pregnant. Without hormones, what happens ?
What do hormones do?
Estrogen
Estrogen is the principal female reproductive hormone. It is a steroid hormone and acts by receptor. There are estrogen receptors all over the body. It can have an effect wherever there are receptors. Examples include the uterus, as we have seen, but they also include the urogenital tract, i.e. vagina, perineum, bladder. Other examples are the bones, skin, breast, blood vessels and of course, the brain. Therefore withdrawal from estrogen produces findings and symptoms in all these areas.
Progesterone
In the course of a normal menstrual cycle, progesterone acts to consolidate and later clean out the uterine lining in preparation for the next cycle. If for some reason, ovulation is delayed, the patient may go on without a surge in progesterone in a state of chronic estrogenized anovulation. Since the estrogen causes the glandular cells in the lining of the uterus to proliferate, this abnormally prolonged exposure to estrogen alone can lead to an overgrowth of those cells, and they can even become precancerous. Clearly this function of progesterone is essential.
Aside from this, progesterone also is part of producing PMS, now called PMDD, premenstrual dysphoric disorder, a mood disorder characterized by irritability and sadness. If progesterone is dominant in the system, it can adversely affect the lipid profile. High doses of synthetic progesterone like Depo Provera have been associated with bone loss especially in teenagers. Finally systemic synthetic progestins added to estrogen for post menopausal hormone therapy confer an increased risk of both breast cancer and cardiovascular disease when compared with estrogen alone given systemically.
It is tempting to think of estrogen as the good hormone, and progesterone the bad, but in the reproductive years, they are both necessary to maintain fertility and keep the uterus healthy. After menopause, it is a different story.
The years of transition to menopause are called perimenopause. During this time of the waning of reproductive hormones, we notice a certain set of signs and symptoms, though they vary in each individual. For example, women experience hot flashes, which are result of vasomotor instability, and they notice insomnia and a deterioration of mood and memory. Objectively, bone density is lost, and the risk of heart disease increases. Finally there is atrophy of the pelvic and urogenital areas, producing dryness.
How can we manage all these changes to feel good and stay healthy ? Learn more in our section Menopause Management.