Etonogestrel-d 6 is deuterium labeled Etonogestrel. Etonogestrel (3-Oxodesogestrel), a biologically active metabolite of progestin Desogestrel, binds with high affinity to progesterone receptors and estrogen receptors in the target organs. Etonogestrel induce FKBP51 mRNA and protein expression in cultured human endometrial stromal cells (HESCs).