Bioidentical Hormones: Flap? Or No Flap?

Suzanne Somers touts them in her bestselling book, Ageless: The Naked Truth about Bioidentical Hormones. Oprah promotes their use. On the other hand, the Harvard Medical School, the North American Menopause Society, and the Endocrine Society take a more cautionary position toward compounded bioidentical hormones. And I find that many of my patients are just confused.

So what are bioidentical hormones and what’s all the controversy surrounding them?

We’ve written a lot on Middlesexmd.com about the importance of estrogen to vaginal health and sexual function. We’ve also discussed various options for replacing estrogen and enhancing vaginal comfort. And we explored the latest thinking about hormone replacement therapy (HRT).

In a nutshell, estrogen is critical to sexual comfort and function, and that’s the hormone we lose during menopause. Most therapies revolve around replacing estrogen to treat menopausal symptoms.

For many years, Premarin was the estrogen replacement of choice. This is a synthetic estrogen made from the urine of pregnant mares, which, according to the Harvard Women’s Health Watch,  “contains a mix of estrogens (some unique to horses), steroids, and various other substances.”

Bioidentical hormones, on the other hand, are defined by the Endocrine Society as “compounds that have exactly the same chemical and molecular structure as hormones that are produced in the human body.” Bioidentical hormones are usually extracted from plant sources.

Pharmaceutical companies manufacture many brands of bioidentical estrogens, such as Vivelle, Elestrin, Divigel, Evamist and one brand of bioidentical progesterone (Prometrium). These are FDA-approved bioidentical hormones. About 95 percent of my patients are on these FDA-approved bioidentical hormones. All hormones, whether they are synthetic or bioidentical, are labeled with the black-box warnings mandated since the massive Women’s Health Initiative study linked slightly higher rates of breast cancer, blood clots, and heart disease to hormone replacement therapy.

So far, so good.

Confusion enters in when bioidentical hormones are custom-compounded by pharmacies. Sometimes there are good reasons for a doctor to prescribe a custom-compounded hormone, if a patient is allergic to some agent in the FDA-approved hormones, for example, or if her dosage can be lower than those produced by pharmaceutical companies.

But hormones made by custom compounders aren’t subject to FDA oversight, nor must they adhere to FDA-approved processes. These custom hormones don’t come with black-box warnings because they don’t fall under the FDA umbrella.

In actual practice, there may not be that much difference between custom hormones and FDA-approved hormones. According to the Harvard Women’s Health Watch, in a 2001 random test of 37 hormone products from 12 compounding pharmacies, almost one-quarter (24 percent) were less potent than prescribed, while 2 percent of FDA-approved products were less potent.

The other problem with custom compounds is cost. Health insurance usually doesn’t cover them, so the regimen gets expensive very quickly.

While custom compounds may be a helpful option for some women, the controversy surrounds the claims about them made by celebrities like Suzanne Somers and even by some clinicians.

In the introduction to her book, Somers writes, “This new approach to health [bioidentical hormone replacement therapy] gives you back your lean body, shining hair, and thick skin, provided you are eating correctly and exercising in moderation. This new medicine allows your brain to work perfectly and offers the greatest defense against cancer, heart attack, and Alzheimer’s disease. Don’t you want that?”

Well, who wouldn’t? But like most claims that sounds too good to be true, so is this one.

The truth is that bioidentical compounds, no matter how “natural and safe” they may sound, are still drugs. There’s no scientific evidence that their effect is any different than synthetic hormones. Also, because hormonal levels vary from day to day, even from hour to hour, attempting to customize hormonal treatments is tricky business. “There’s no stable ‘normal’ value at all for salivary or blood levels of these hormones or levels that correlate with symptoms,” says the Harvard Women’s Health Watch.

The current medical advice is to take the lowest possible dosage of any hormone—synthetic or bioidentical—for the shortest period of time to alleviate menopausal symptoms. There is, unfortunately, no way to turn back the clock—"natural" or otherwise. In the meantime, the hormones that work for a woman can significantly improve her quality of life.