Critics of CBHT, which includes the North American Menopause Society2 and the American College of Obstetricians and Gynecologists,3 highlight that the main difference between CBHT and HT is lack of FDA regulation over the CBHT industry. Many of these agents are delivered transdermally and therefore are classified as “dietary supplements.” As such, they do not require FDA regulation or proof of safety or efficacy.
Dr. Emma C. Rossi
Lack of FDA approval allows CBHs to be distributed without package inserts and boxed warnings (such as the standard warnings about MI, venous thromboembolic events, and breast cancer). The absence of FDA approval also allows them to avoid FDA-regulated guarantees about purity, potency, and efficacy. Audits of CBHs have shown high rates of discrepancy between stated and measured potency, including observations of both much lower and much higher than stated strength.4
Why would dosing accuracy be important in hormone therapy prescription? If a woman taking estrogen therapy is not receiving adequate cotreatment with progesterone because of either omission or a subtherapeutic product, she increases her risk for endometrial cancer.
What drives patients’ decision to use compounded bioidentical hormones?
After the Womens’ Health Initiative study was published in 20025, all FDA-regulated estrogen preparations were required to carry specific warnings, particularly in relation to the increased risk for MI, venous thromboembolic events, and breast cancer. There was a clear uptake in use of CBHT after this study was reported. By avoiding FDA regulations, distributors of CBHTs may have avoided providing Womens’ Health Initiative information to patients. The absence of an insert with a written warning, in and of itself, makes these preparations seem safer to the patient.
But is it entirely a lack of information that drives demand for CBHTs? Surveys of current or former users suggest the motivations are more complex than that. A survey of 21 past or present CBHT users inquired about reasons for use of CBHT over conventional HT.6 Their responses were categorized as either push motivations away from conventional therapy versus pull motivations toward CBHT. About 95% of current and former users cited distrust of the biomedicine and pharmaceutical industry as reasons for use of CBHT. Fear about the safety of conventional HT, particularly with respect to cancer risk, also was strongly cited at 81%. Motivations pulling toward CBHT included its efficacy (76%) and perception that CBHT is “safer” than conventional HT (76%).
Women in this study also appreciated the tailored, individualized approach that often is associated with CBHT, in which providers spend long consultations discussing individual patient needs and concerns. They enjoy the idea of a customized blend that is created, as opposed to a standard dosing regimen, and intuitively trust the reliability of blood and saliva testing as a prescriptive tool.
Are bioidentical hormones safe with respect to cancer risk?
Hormones themselves are not inert substances, including those derived in vivo and those from plants. They have powerful effects in the human body and can promote malignant transformation or proliferation, alter metabolic pathways, stimulate vascular tone, influence coagulation pathways, along with many other effects. A hormone’s potential for deleterious effect can be present regardless of how that hormone is synthesized, procured, or prepared. While there are no data to suggest that CBHT is associated with increased cancer risk, compared with conventional HT, there are by no means any data to suggest it is safer. Unopposed compounded estrogens place women at increased risk for endometrial cancers, and the prolonged use of hormonal therapy, compounded or otherwise, after menopause increases the risk for breast cancer.