Bioidentical hormones are made in
the laboratory and are based on compounds found in plants (usually soy beans or
wild yams). Unlike supplements containing soy or wild yam extract, a
bioidentical hormone product has been processed by a specially trained
compounding pharmacist.
After the plant-based hormone is
processed, its structure is said to be identical to the
estrogen,
progesterone, or
androgen hormone your body produces. (Well-designed
studies have yet to prove this theory.1) A compounding
pharmacist can offer you a custom-made formulation in one of many forms, such
as a capsule, skin cream or gel, tablet to dissolve under your tongue,
suppository, or nose spray. Some commonly prescribed estrogens and
progesterones are bioidenticals, such as Estrace (estradiol).
Estrogen-progestin
hormone replacement therapy (HRT) can cause symptoms
that lead many women to stop taking them, such as bloating, breast tenderness,
weight gain, and uterine bleeding. These symptoms are thought to be caused by
the synthetic progestin.2
Doctors who
prescribe bioidentical hormones report that many women have less or no trouble
with the symptoms that they get when using synthetic estrogen-progestin
HRT.3 This improvement has been linked to bioidentical
progesterone.
Just like synthetic HRT, bioidentical hormone
replacement is prescribed to increase or stabilize a woman's hormone levels.
This is generally done during perimenopause, when hormone levels change
unpredictably, and after menopause, when the hormones drop to low levels.
The most important fact to remember about taking bioidentical HRT
is that its risks are not yet well understood. It may have the same breast cancer, stroke, blood clot, heart disease, and dementia risks that synthetic HRT has. 4