The Basics of Bioidentical Hormones

Hormone replacement therapy (HRT) for women with menopausal symptoms can be divided into two eras: Before 2002 and After 2002. That's when the Women's Health Initiative (WHI) halted studies of a specific type of estrogen/progesterone therapy because they were linked to significant health risks. Despite the fact that only one type of medication was tested (Premarin-made from pregnant horse urine); many doctors quit prescribing HRT altogether. Many women were forced to suffer with sometimes debilitating symptoms or seek relief from estrogen sources purchased at health food stores or specialty pharmacies. And then came bioidentical hormones, the answer many scientists, doctors and women were looking for. So, what are they, and how can they help you? 

Many women believe they have to see an herbal or natural health care provider to find bioidentical hormones.  Buy, in fact, your regular gynecologist probably prescribes them every day, and you can buy them at your usual pharmacy.

According to Harvard Medical School's Health Publications, "Bioidentical Hormones are identical in molecular structure to the hormones women make in their bodies. They're not found in this form in nature but are made, or synthesized, from a plant chemical extracted from yams and soy. Bioidentical estrogens are 17 beta-estradiol, estrone, and estriol. (Estradiol is the form of estrogen that decreases at menopause.) Bioidentical progesterone is simply progesterone. It's finely ground in the laboratory for better absorption in the body.

Bioidentical hormone therapy is often called "natural hormone therapy" because bioidentical hormones act in the body just like the hormones we produce." 

We've learned a lot about how to replace hormones more safely with bioidentical hormones. The WHI studies only tested one non-bioidentical hormone replacement medication, prescribed in a pill and at one dose. Now we know that this type of estrogen/progesterone changes chemical structure while going through the digestion process and liver. This may be why it caused so many health problems. 

Newer bioidentical hormones are prescribed as a patch, ring or cream and in varying doses that allows them to bypass the liver and enter the bloodstream directly through the skin. Some contain estrogen only. Others are combined with progesterone. They don't come from horses and they're not prescribed as one-dose-fits-all therapy. Your body can't tell the difference between the hormones you made yourself and bioidentical hormones. 

Compounding pharmacies can whip up special doses and combinations of bioidentical hormones (and this is partly how bioidentical hormones gained acceptance), but these compounds aren't necessarily FDA-approved, covered by insurance, or necessary. 

You no longer have to find a "natural medicine" specialist to get bioidentical hormones, though they may provide excellent healthcare and customized hormone replacement therapy. Now you can visit any up-to-date gynecologist for menopausal symptom relief.  Ask about readily available products like Vivelle, Alora, Climara, Esclim, Estraderm, Estragel, Estrasorb, Estring, and Estrace cream (available at your regular pharmacy).  Women with specific health concerns should still use caution when taking any type of hormone replacement therapy, but it's good to know that, once again, there's a choice.


Harvard Health Publications

Harvard Medical School

What are Bioidentical Hormones?