HRT- Estriol

Different Forms of HRT: Estriol

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.

Standard dosage: ranges from 2 to 8 mg
Pros: Natural; appears to have low risks compared to other estrogens; may help prevent breast cancer
Cons: Often need a very high dose to eliminate symptoms -- which can cause nausea