Estriol Vs. Estrogen

Hormones play an important role in health. In the past few decades, drug companies have developed synthetic versions of female hormones to try and help with menopausal symptoms. Plant derived bioidentical hormones are also available.

Definition

• Estrogen is a generic name for a group of hormones that regulate secondary sexual characteristics in females. One of these hormones is estriol.

Safety

• Estriol is the weakest estrogen, and lots of it is produced during pregnancy with no ill effects. All types of synthetic estrogens have been shown to increase the risk of breast cancer, blood clots and stroke.

Pregnancy

• A study done by Kirkish, Barclay, Parra, Compton and McCann in 1978 recommended that accurate and faster readings could be had using estriol instead of urinary estrogen to determine fetal health.

FDA

• The FDA still approves the use of estradiol and estrone, despite the Women's Health Initiative findings that they increase the risk of cancer and stroke. Estriol has not yet been approved in the U.S.

Hormone Replacement Therapy

• Traditional hormone therapy includes synthetic forms of the estrogens estradiol or estrone, along with synthetic progesterone. Some pharmacies compound estriol vaginal cream as a weaker alternative, but in large doses, synthetic and animal derived estriol can still pose a risk for breast cancer, per Punnonen and Lukola in their study published in the Journal of Endocrinological Investigation, July-August, 1982.