What You Need to Know About Bioidentical Hormone Therapy for Menopausal Symptoms

Increasing numbers of peri- and post-menopausal women request “bioidentical” hormones rather than the hormones available in commonly used FDA-approved hormone replacement therapies.  

What Exactly is a Bioidentiacal Hormone?

The term “bioidentical” means that a hormone is chemically and structurally identical to the hormone that the body naturally produces. Bioidentical hormone therapy used to treat menopausal symptoms typically contains estradiol which is, in fact, identical to the estradiol used in traditional hormone therapy. Thus, the term bioidentical hormone therapy can be confusing; there are bioidentical hormones approved by the FDA, but there are also compounded bioidentical hormone therapies.  

FDA-approved bioidentical hormones include estradiol, estrone, and micronized progesterone, which are regulated and monitored for purity and efficacy according to FDA guidelines. The efficacy and safety of these products have been established through rigorous testing in randomized controlled trials. These products require a prescription. 

Compounded bioidentical hormone therapies are prepared by a compounding pharmacy according to a provider’s specifications. These therapies are custom-blended and typically combine multiple hormones including estradiol, estrone, estriol, DHEA, testosterone, and progesterone. The efficacy of these preparations have not been assessed in randomized controlled trials and often contain untested combinations and dosages of hormones. These formulations may also be administered by nonstandard or untested routes, such as topical creams, subdermal implants or pellets, injections, or oral lozenges. Bioidentical hormone therapy is most commonly recommended by naturopathic doctors.  

Is Bioidentical Hormone Therapy Safer or More Effective?

In the media, women are often given the message that bioidentical hormones are safer and more effective than synthetic hormones; however, the bottom line is that we have no evidence to suggest that bioidentical hormones are any safer or more advantageous for women than traditional hormone treatments. 

Although there is a tendency to think of bioidentical hormones as “all-natural”, they, like the hormones used in traditional hormone therapies, are manufactured in the laboratory. Thus, bioidentical hormone therapy carries many of the same risks as traditional estrogen replacement therapy, including increased risk of blood clots, stroke, endometrial cancer and breast cancer. Because there is not consistent package labeling for these compounded products, consumers may not be fully aware of the potential for serious side effects.

To date, there have been no randomized, controlled trials comparing compounded bioidentical hormone therapy with placebo or FDA-approved hormone therapies for menopausal symptoms. Furthermore, there is no scientific evidence to support the notion that bioidentical hormone therapy has fewer risks than FDA-approved hormone therapies. In fact,  many professional organizations are concerned that these compounded preparations may carry additional risks. There is the potential for dose variability (either overdosing or underdosing), inconsistent bioavailability, and contamination. While compounding pharmacies are expected to comply with USP Standards for the preparation of these hormone therapies, compounded products are not routinely tested, and pharmacies are not required to collect information on adverse events.

Without FDA oversight and regulation, there is no guarantee that custom-made compounded preparations containing bioidentical hormones provide predictable therapeutic levels of hormones. 

Not enough Data, Oversight for the Use of Bioidentical Hormone Therapy

 The North American Menopause Society (NAMS) and other medical organizations have cautioned against the use of bioidentical hormones: “Little or no scientific or medical evidence supports claims that bioidentical hormones are safer or more effective than more traditional FDA-approved therapies. In addition, many custom-compounded “bioidentical hormone” formulations are not subject to FDA oversight and can be inconsistent in dose and purity.”  

We agree. We do not have adequate information to support the use of these bioidentical preparations for the treatment of menopausal symptoms.  

Ruta Nonacs, MD PhD