Endometriosis is a common reproductive disease where cells of the uterus grow in other areas of the body. The disease frequently causes severe pelvic pain, and many women with endometriosis experience infertility. Progesterone, a steroid hormone involved in the menstrual cycle and pregnancy, is thought to play an important anti-inflammatory role in the development of endometriosis.
Researchers in the Specialized Cooperative Centers Program in Reproduction and Infertility Research, supported by the NICHD Fertility and Infertility Branch, examined tissue from women with and without endometriosis to evaluate how the interaction between progesterone and the expression of a specific gene in the uterus affects the infertility associated with this disease.
Laboratory analysis of tissue samples showed a striking difference between women who had endometriosis and women who did not. In the healthy women, tissue samples exposed to progesterone showed an increase in the expression of a particular gene. By contrast, the tissues from women with endometriosis did not respond to progesterone in the same way—these tissues showed almost no gene expression at all. Scientists theorized that since the interaction between progesterone and this gene is important to the normal reproductive process, it is likely that disruptions in this interaction due to endometriosis contribute to infertility.
Understanding the mechanisms underlying endometriosis-associated infertility may ultimately help researchers identify new treatment methods (PMID: 22789143).