How Safe Are Bioidentical Hormones?

Bioidentical hormones are made to be molecularly identical to the hormones produced in the body. Many women, dealing with menopausal symptoms, switched to bioidentical hormones from conventional hormones when it was discovered that there were substantial risks associated with conventional hormone replacement therapy. Bioidentical hormones are thought to be safer as they are metabolized in the body in the same way as natural hormones.

History

• In 2002, the Women's Health Initiative study of progesterone plus estrogen use for menopausal symptoms was ended when it was discovered that the risks associated with progesterone and estrogen use outweighed the benefits. Conventional hormone replacement therapy use dropped by 50 percent as a result. The hormones used in the study were primarily either synthetic or derived from pregnant horse urine, neither of which are chemically identical to human hormones. Health care providers and women began researching alternatives, and many have turned to bioidentical hormones as a solution.

New Studies

• Although the synthetic hormones (including those derived from horse urine) have been widely researched and studied, the use of bioidentical hormones is so new that there have not been many studies. Although bioidentical hormones have been available for 20 years, they were not widely used until after the Women's Health Initiative study. However, a few of the studies that have been done show promising results. Some show the health risks of bioidentical hormones to be the same as conventional hormones, but a few show that bioidentical hormones have less risk and some even show benefits. Recently, a French study suggested that bioidentical progesterone might protect against breast cancer and heart attacks, and some French researchers think progesterone may even lower the risk of dementia.

Controversy

• Many doctors are still against the use of bioidentical hormones. In fact, in February 2009 the American College of Obstetricians and Gynecologists stood by its position that there are no proven benefits to safety or efficacy of bioidentical hormones. Proponents argue that the reason bioidentical hormones are not more widely accepted is that, as a bioidentical structure, they can't be patented and therefore pharmaceutical companies can't make money from them. Proponents point to the fact that some bioidentical hormones are already accepted and in use by doctors--when they come in a patented, marketable form. Examples are the Vivelle patch and Estrogel.

Continuing Debate

• While many doctors advise against bioidentical hormone therapies, many think it is the ideal solution. They point to the fact that bioidentical hormones are used in the body in the exact way as naturally occurring hormones. Bioidentical hormone replacement can also be adjusted to individual applications, whereas conventional hormone therapy cannot. Some organizations can't make up their minds, and advise both for-and-against, such as the North American Menopause Society (NAMS). NAMS's position is both that bioidentical hormones provide benefits that aren't available through conventional hormone therapy, and that they don't recommend these products.

Potential

• Hopefully, more studies will be conducted for bioidentical hormones. If bioidentical hormones can be proven safe, millions of women could benefit.