What is "etonogestrel"

n. A steroidal progestin used in hormonal contraceptives.

Etonogestrel ( INN, USAN, BAN), also known as 11-methylenelevonorgestrel and 3-keto-desogestrel, is a steroidal progestin used in hormonal contraceptives, most notably the subdermal implants Nexplanon and Implanon and the vaginal ring NuvaRing. It was first introduced, as Implanon in Indonesia, in 1998, and was subsequently marketed in the United Kingdom shortly thereafter and in the United States in 2006. Etonogestrel is significantly less androgenic than levonorgestrel and norethisterone, and it does not cause a decrease in sex hormone-binding globulin levels, but it is still associated with acne in up to 13% of patients when used as an implant, though this only accounts for 1% of premature removals.

Etonogestrel is the active metabolite of the inactive prodrug desogestrel, one of two third-generation progestins found in some epidemiological studies of combined oral contraceptive pills to be associated with a higher risk of venous thrombosis than combined oral contraceptive pills containing certain second-generation progestins. Because hormones are released continuously from NuvaRing, peak and total estrogen and progestin doses are significantly lower than with combined oral contraceptives, although it is not known whether this lowers the risk of blood clots. It is effective within the first 8 hours of insertion.