Estrogen Levels in a Woman’s Body Change
Estrogen levels in a woman’s body change every 6 to 18 hours, as well as changing from day to day during each menstrual cycle, during her childbearing years and changing as well during her menopause and post menopausal years. The amount of change in the amount of estrogen made, the pattern of changes in the amounts of estrogen made, and the speed at which the estrogens are broken down are totally unique to each woman.
The following illustration shows the general pattern of estradiol production throughout a woman’s life.
Ovarian Estradiol Production Over A Woman’s Lifetime
As can be seen in the illustration, a girl’s estrogen production fluctuates quite often during puberty, leading to many different feelings and changes before her levels of estrogen stabilize. There appear to be even wilder fluctuations in a woman’s estrogen during the pre–menopausal phase, leading to many physical and emotional changes.
Estrogen in general, has many roles in a woman’s body including:
- Helping to protect the heart
- Making a woman feel sensual
- Helping to protect brain function
- Helping to preserve bone strength
- Keeping a woman’s vagina lubricated
- Lifting and stabilizing a woman’s moods
- Stimulating growth in a girl’s breasts, ovaries and uterus starting at puberty
- Stimulating maternal behavior ie. it promotes childbirth and child care
- Participating in the growth and maturation of egg bearing follicles during each menstrual cycle
A woman’s body makes approximately 30 different forms of estrogen. The 3 most common forms of estrogen are estrone, estradiol, and estriol. Each of these three estrogens has different functions in the body as well as different strengths or affinity for estrogen receptor sites in the body.
In the past estradiol was recognized as the strongest estrogen made in a woman’s body and most of the research was, and still is being done on it. From the early research the first birth control pills [BCP] were developed. Also, this is the only estrogen that the medical profession and many labs look at in tests. It is the estrogen that helps build up the lining in the uterus every menstrual cycle, is the main estrogen made by the ovaries in the reproductive years, is credited with helping to prevent osteoporosis, and is credited for making a woman feel like a woman. It has been found that 10 to 20% of the estrogens that a woman’s body makes is estradiol. It is often referred to as E2.
Referred to as E3, estriol is considered to be the weakest of the estrogens yet it appears to help regulate [control the use of] the other estrogens in a woman’s body. It is found in its highest levels during pregnancy leading to the belief that estriol helps protect the fetus [growing baby] from the effect of other hormones. Although estriol is not associated with preventing osteoporosis, it was researched by Dr. Lemon, M.D. in the late 1970s and found to protect women from breast cancer. Estriol has been researched extensively in both Europe and Japan and the research has shown it to be very safe and effective. Unfortunately, the FDA in the United States has not looked at the research from these countries and therefore is of the opinion that estriol does not have any data regarding its safety. It has been found that 60 to 80% of the estrogens that a woman’s body makes is estriol.
It has been found that 10 to 20% of the estrogens that a woman’s body makes is estrone. As the production of estradiol from the ovaries decreases, the closer a woman gets to menopause, the production of estrone increases. It is made mainly in a woman’s fatty tissue and liver during menopause. Therefore, estrone can still be made in a woman’s body even if her ovaries have been surgically removed. Although estrone [also called E1] is considered to be one of the estrogens that helps to protect a woman against osteoporosis, excess amounts of estrone are believed to be dangerous in the body and increase the risk of a woman developing such problems as gall bladder disease, fibroids, and breast cancer especially if she is overweight. In spite of these facts, many practitioners do not test for estrone, and still prescribe biologically identical [bio–identical] estrone to a woman as part of her estrogen treatment.
There are many estrogen receptors / target cells throughout a woman’s body than any of a woman’s estrogens can attach to. Some of the various locations of estrogen receptors / target cells are a woman’s brain, eyes, breasts, bones, the lining of blood vessels, liver, ovaries, uterus, kidneys, and adrenal glands.