The U.S. Food and Drug Administration (FDA) has begun enforcement action against seven compounding pharmacies, stating that the claims made by these pharmacies about safety and efficacy of compounded "bioidentical hormones" are false and misleading, with no credible scientific evidence to support them (www.fda.gov).
While many postmenopausal women are turning to "natural" or "bioidentical" hormone therapy because of safety concerns about conventional hormone preparations, there is no evidence that these products are either safe or effective. The "bioidentical" approach generally refers to the prescribing of individualized doses of steroid hormones (compounded as pills, gels, sublingual tablets, or suppositories). The quality of compounded products may be substandard in some cases.
The hormones most commonly compounded are estradiol, estrone, estriol, progesterone, testosterone, and DHEA. Women typically are asked to submit saliva or blood samples to measure baseline hormone concentrations. Based upon the results, the prescriber selects the individual hormones and doses to be compounded.
Proponents of this approach claim that these preparations are effective for menopausal symptoms, yet are safer and better tolerated than commercially available preparations. However, a systematic review of the literature concluded that, while some of these products may decrease hot flushes, there is no evidence that "bioidentical" hormones have any advantage over conventional hormone therapies and that their safety has not been established. In addition, this approach is expensive, as many providers perform frequent and unnecessary biochemical monitoring.
From: UpToDate