Bioidentical Hormone Replacement Therapy (BHRT)

In general, hormone therapy is still considered the most effective treatment for symptoms. But women are sometimes hesitant of treatment because of fear of side effects including cancers, heart disease and strokes.

The controversial WHI made some women worried about estrogen's link with breast cancer. Still others were opposed to taking drugs for symptoms because doing so implies that menopause is a disease rather than a normal life passage. Some women also objected to the use of pregnant mares' urine.

BHRT are "natural" hormones. To define natural, it is any product whose principal ingredient has an animal, plant, or mineral source is technically natural. It doesn't matter whether the substance is ground, put into capsules, and sold over the counter or extracted in a laboratory, manufactured by a pharmaceutical company, and made available only by prescription. For example, the soy plant is the source of supplements that some women take to ease menopausal symptoms; it's also used, along with yams, to make the estrogen in the FDA-approved hormone drug Estrace.

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. Bioidentical progesterone is simply progesterone. It's micronized (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. But here again, that tricky word natural can be confusing. Pregnant mares' urine is natural, but Premarin is not bioidentical, at least not to human estrogen.

Technically, the body cannot distinguish bioidentical hormones from the ones your ovaries produce. On a blood test, your total estradiol reflects the bioidentical estradiol you've taken as well as the estradiol your body makes. On the other hand, Premarin is metabolized into various forms of estrogen that aren't measured by standard laboratory tests. One advantage of bioidentical estrogen over Premarin is that estrogen levels can be monitored more precisely and treatment individualized accordingly.

Bioidentical hormones and compounding

Natural hormones are sometimes available over the counter at supermarkets and health food stores or on the internet. It also can be custom-mixed at a compounding pharmacy. Custom compounding can be used to prepare combinations, doses, or preparations (such as lozenges or suppositories) not routinely available, or to order hormones not approved for women, such as testosterone and DHEA. Compounding pharmacies use some of the same ingredients that are made into FDA-approved products, but their products are not FDA-approved or regulated. Your physicianshould have considerable experience with bioidentical hormones and compounding pharmacies and you should ask them about this when you consult your physician. You should discuss the type of delivery system too. For example, when estrogen is taken as a pill, it's first processed through the liver. This stimulates proteins associated with heart disease and stroke, such as C-reactive protein, activated protein C, and clotting factors. When delivered by transdermal patch, estrogen isn't first processed by the liver and does not have these side effects.