Transdermal natural progesterone cream for postmenopausal women: inconsistent data and complex pharmacokinetics

Transdermal progesterone cream (PC) is propagated as a possible alternative to hormone replacement therapy (HRT) in the management of menopausal symptoms and treatment of osteoporosis. Nonetheless, considerable concerns were raised regarding the inconsistent results and the credibility of some studies that were not peer-reviewed. Further, the complex nature and diversity of the pharmacokinetics of progesterone led to difficult interpretation of the findings. Given the current best available evidence, using PC for postmenopausal therapy regimens should be considered as an unsubstantiated treatment option, and its clinical applications must be restricted to well-designed interventional trials that assess its efficacy and safety.