Bioidentical Hormones: Why Is There Controversy and How Do You Stay Safe?

Hormone therapy for menopause
Hormone therapy for menopause
Women seeking relief from menopausal symptoms must be aware of the risks, benefits of different treatment options.

Hormone therapy for menopausal women is a topic that generates a great deal of passion, anecdote and opinion. At times the media, doctors, friends and various sources of peer pressure all seem to be saying completely different things to a woman who is considering how best to treat her menopausal symptoms

When the findings of the Women’s Health Initiative (WHI) Hormone Studies were published in 2002 and 2004, many women were informed that they should stop their menopausal hormone therapy immediately, regardless of their symptoms. Women who were at very low risk for complications of hormone therapy also chose to stop their treatment.

This era marked the aggressive advent of custom compounded hormone therapy marketed to menopausal women, and the practice has grown appreciably over the past decade.

Compounding of hormones has historically been a legal practice in the United States. It is typically used when a patient is unable to take any of the FDA approved drugs that are available due to allergy to one of the excipients or “fillers” in the pill, or when there is no FDA approved equivalent drug available to treat a patient’s symptoms. In this case, the physician and pharmacist act collaboratively to provide optimal therapy.

The situation outlined above is not the case with custom compounded hormones targeted for the treatment of menopausal symptoms. These substances are not FDA approved, and many women are unaware of this fact. 

There are reasons to be concerned about using hormones that are not FDA approved. Compounding pharmacies are not held to the same standards as pharmaceutical companies that manufacture prescription drugs. This became clear to many Americans when a series of fatalities from fungal meningitis was traced to a New England compounding pharmacy that did not adhere to appropriate standards. 

Custom compounded hormones for the treatment of menopause are often marketed with attractive concepts of therapy, such as restoration of youthful hormone levels, reversal of aging and superior preparations that are more physiologic than FDA approved prescription hormones. These concepts are simply not based in fact, and the purveyors of these substances are not accountable for proof of claim. This is because custom compounded menopausal hormones have fallen through a legal loophole that classifies them as “supplements” and not as drugs.

Now let’s talk about “bioidentical.” This is not a medical or scientific phrase. It is a marketing phrase that highlights the supposed superiority of custom compounded hormones over FDA approved hormones. Consumers should be aware that the two naturally occurring sex steroids made by women’s ovaries that are used to treat menopausal symptoms are estradiol and progesterone. Both of these hormones are available in FDA approved, pharmaceutical grade preparations.

Perhaps even more important, the FDA approved hormones, whether strictly bioidentical or not, have a large body of medical evidence backing their risks and benefits. This is not the case for compounded “bioidentical” hormones. The lack of evidence for harm simply reflects a lack of rigorous scientific testing. By no means does it demonstrate safety. Again, here is where the marketing of these substances really tends to stretch the truth. 

Women of America, wake up!

There is no reason to subject yourself to the risks of less well-tested hormones unless you have very unusual dose requirements or allergies to all of the pharmaceutical preparations available. Stick with the tried and true and ask your health care provider to help you navigate through the risks and benefits that you may be subjected to with hormone therapy. Your practitioner should also be able to provide you with information on some of the new, FDA approved non-hormonal alternatives that are available. Make an informed decision and stay safe and free of annoying hot flashes and other symptoms that temporarily challenge us women in midlife!

Nanette Santoro, MD, is professor and E. Stewart Taylor Chair of Obstetrics and Gynecology at the University of Colorado at Denver.


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