Background to Hormone Replacement in Menopause
Why do you need this information about menopause hormones when you just want to find the best treatment?Understanding the changes in your body can be very empowering and will give you a sense of control. It is much easier to choose a treatment when you know what the treatment is supposed to do.
We are providing you this information so you are not as ignorant as we were when we started menopause. We had no clue what changes were happening in our body. We just knew that the reproductive years were over and that we were feeling miserable.
What are Hormones?
Very simplistically stated, hormones are the messengers in the body. They are sending signals from one cell to another to regulate the functioning of your body. Cells need to have specific hormone receptors to receive the signal and to activate their specific function.
Picture the hormones in your body as an orchestra: Every hormone has a specific part to play and all of them together produce a harmonious piece of music. If one or the other of the “hormone” players gets out of balance, the result is disharmony and confusion – resulting in symptoms.
Female Hormones
During a woman’s reproductive years, the female hormones go through a more or less regular cycle, causing a well-ordered series of events. 
This cycle is regulated by two hormones from the pituitary gland: follicle-stimulating hormone (FSH) and luteinizing hormone (LH).
FSH causes eggs to ripen and to begin producing estrogen. This estrogen stimulates the lining of the uterus to thicken in preparation of pregnancy. At this time, the testosterone levels are also at their peak to stimulate the libido.
The LH causes the follicle to release one egg (ovulation) when estrogen is at its peak. After the follicle released the egg, the remnant (corpus luteum) starts producing progesterone to nurture the uterine lining even more.
If no pregnancy occurs, both estrogen and progesterone production drops, the uterus sheds its lining and menstruation occurs.
What is Estrogen?
Estrogen is the most important sex hormone for women. Together with progesterone it regulates our menstrual cycle, gives you your womanly body and regulates the reproductive system.
But it also plays a role in a multitude of other body functions that have nothing to do with the reproductive system (like the regulation of the core body temperature plus hundreds more).
Estrogen is actually a group of three steroids:
- Estradiol
- Estriol
- Estrone
During the reproductive years, women’s ovaries produce mostly estradiol, the most active of the estrogens.
Estriol is produced in any significant amount only during pregnancy. It is considered a “weaker” estrogen than either estradiol or estrone. Estriol is the only hormone in this group that does not have an FDA approved version.
After menopause, the main source of estrogen is estrone which is produced in the adrenal glands, and other organs. Fat and muscle cells also produce some estrone. Too much estrone can stimulate breast tissue growth and can lead to increase risk of breast cancer. (BTW: Premarin, the much discussed synthetic form of this hormone, contains 50% estrone sulfate).
To make matters even more complex, women’s bodies have two different kinds of estrogen receptors. One kind is more predominant in the reproductive organs, breast tissue and liver, the other kind is found in the brain, bone, bone marrow and blood vessels. The activity of the different types of estrogen depends on which kind of receptor is used, and which tissue is affected.
But not only do the different kinds of estrogen influence the effect it has, the way women take estrogen affects how it is metabolized.
If you take it as a pill, it is metabolized through the liver and has different effects or side-effects than if you use a patch or cream. (Women who take oral estrogens should minimize their alcohol intake to limit the negative effects of the metabolism by the liver.)
So with different kinds of estrogen plus different kinds of receptors, you may have an idea why it is so difficult to find a risk-free estrogen supplement.
Menopause Hormones – What Changes?
During peri-menopause, when the hormone shift begins in earnest, the pituitary gland sends out more FSH to stimulate the ripening of more eggs. This is the reason for the wild fluctuations in estrogen levels during this time (with the related symptoms). Some cycles will have unusually high levels of estrogen, some very low levels and some cycles will be normal.
The closer you get to menopause, even the higher FSH levels will fail to stimulate the follicles to do their job. Your menstrual cycle will become more and more erratic and toward the later part of the peri-menopause stage, you will skip more and more menstrual periods.
How much estrogen is produced by the ovaries right after menopause depends on the state of the remaining follicles. This is also the time with the highest number and most severe symptoms, especially those depended on estrogen levels.
When no egg is released, there is no corpus luteum to produce progesterone. This causes the estrogen dominance symptoms during late peri-menopause because there is still a relatively high level of estrogen. In the later stages of your transition, when estrogen levels drop, these symptoms disappear.
The first year after menopause (the point when you haven’t had a period for 12 consecutive months) is when the drop in menopause hormones is the most dramatic.
Remember: It is often not the amount of a hormone that causes the symptoms; important is also the relationship between the various hormones.