Estriol is the weakest of the three major
estrogens in your body. It appears to have a lower risk of breast cancer; and possibly may
have a protective effect on the breasts. Unlike conjugated estrogens or estradiol, when
you take estriol, it isn’t converted into estrone -- which means you
aren’t exposing yourself to the estrogens that have been linked to cancer.This is
one of the main reasons more researchers are looking into the use of estriol alone as an
estrogen replacement, in place of the commonly prescribed conjugated estrogens or
estradiol.
The key plus of estriol is its weakness: It appears to offer the benefits of the
stronger estrogens with fewer of the risks. Tests have indicated that it relieves
menopausal symptoms, and protects against heart disease and osteoporosis, as the other
estrogens do, but doesn’t appear to increase the risk of breast cancer or endometrial
cancer. In fact, many studies indicate that is has an anti-cancer effect, and actually may
work better than tamoxifen for women with breast cancer. In addition, studies conducted in
the United States found that estriol seemed to be a good choice for women who had troubles
tolerating the stronger estrogens.
But the weakness of estriol is also a negative. Because it is so weak, you need a much
higher dosage to get the results you do from the standard dosages of conjugated estrogens
or estradiol. For example, 4 mg of estriol equals 1.25 mgs of conjugated estrogens. In
some studies, many women needed as much as 8 mg a day, however, to get relief from
menopausal symptoms. Unfortunately, often a high dose of estriol causes nausea. Remember,
estriol is the estrogen that rises when you’re pregnant. . . . and suffering from
morning sickness. One way to get the benefits of estriol without the high dosage is opting
for tri-est (above).
Estriol has been widely used for years in Europe and China with great success, but is
currently rarely prescribed in the United States. It’s not a patented drug, so there
is no major pharmaceutical company putting out a brand name estriol. But doctors can have
it formulated by compounding pharmacies -- and the use of it seems to be growing. Probably
you’ll see more use of estriol over the next few years. In the meantime, because of
its unique properties, estriol seems to be a good -- and safe -- choice for estrogen
replacement. It’s well worth talking to your doctor about this.
