Like traditional hormone therapy, some bioidentical products—including estradiol and progesterone in pill form and certain gels, vaginal rings, skin patches, and creams—are FDA-approved drugs. (This chart provides a full list.) However, the bioidentical estrogen estriol is not, nor are any of the products being hawked on the Internet, at cosmetic counters, or in health-food stores. Nor are those formulated in individual compounding pharmacies. The FDA has taken the position that "bioidentical hormones" is a marketing term not recognized by the agency, and the agency "cannot assure their safety or effectiveness" if they haven't been approved as drugs. It has warned several pharmacies to stop making misleading safety and effectiveness claims about their products.
But that hasn't stopped some doctors from claiming that bioidenticals are essential for preventing age-related diseases. In a similar fashion to the way gynecologists used to routinely prescribe Premarin and Prempro to every menopausal woman, these doctors believe that bioidenticals can help stave off breast cancer, heart disease, Alzheimer's, and osteoporosis. "I've reviewed the studies," contends Kent Holtorf, a family practitioner with a private practice in Torrance, California. "Synthetic progestins increase the proliferation of breast cancer cells, whereas bioidentical progesterone decreases it." He says he prescribes progesterone to treat precancerous breast lesions and gives bioidentical estrogen to halt the progression of cardiovascular disease. And he doesn't worry about his patients staying on bioidenticals for years or even decades or see any reason to restrict prescribing them only to those with menopausal symptoms. "I'm not going to say these hormones have no risks," Holtorf says. "There are always risks to anything you take, but I look at particular patients and see if the risks outweigh the benefits."
While Holtorf's practices are certainly on the fringe, more and more doctors these days feel comfortable prescribing FDA-approved bioidentical hormones for the relief of menopausal symptoms. Isaac Schiff, chief of obstetrics-gynecology at Massachusetts General Hospital in Boston, says he doesn't believe there's enough evidence to show bioidenticals are any safer than traditional hormone therapy, but he will prescribe estradiol or progesterone pills if a woman asks for bioidentical hormones to relieve menopausal symptoms. He'll also explain that while estradiol is, indeed, made by the ovaries, it gets converted by the liver into estrone, which is not. "If she wants a true bioidentical, I'll prescribe an estrogen skin patch or gel in which estradiol bypasses the liver and remains in its original form." He also tells patients that believing "one estrogen is safer than another when it comes to breast cancer, I think, is wishful thinking." Others like, Fugh-Berman, believe there's enough evidence now to say that progesterone is probably a safer bet than synthetic progestins when it comes to considering breast cancer risks.
So how should you proceed if you have menopausal symptoms and want to try bioidentical hormones? Here's our user's guide.