Abstract
Topical progesterone creams and gels can be obtained over the counter and/or by prescription from custom-compounding pharmacies and are used by thousands of postmenopausal women for hormonal treatment. However, the effectiveness of these preparations for protecting the endometrium from unopposed estrogen is controversial, due largely to the very low serum progesterone levels that are achieved. Despite these low serum levels, salivary and capillary blood levels are very high and a protective endometrium has been reported in a limited number of studies. Topical alcohol-based, but not water-based, gels appear to yield luteal-phase serum progesterone levels but studies with these preparations are scant. Long-term studies with percutaneous progesterone creams and gels are likely to provide valuable information for treatment of postmenopausal women with this popular route of administration.
ACKNOWLEDGEMENTS
I thank Margaret N. Groves, MPhil, ELS and Mary Stanczyk for their help in the preparation of the manuscript.
Conflict of interest The author reports no conflict of interest. The author alone is responsible for the content and writing of this paper.
Source of funding Nil.