etonogestrel

Etonogestrel is a synthetic progestin used primarily as a long-acting reversible contraceptive. It is available as a subdermal implant (brand names Implanon and Nexplanon) that provides effective contraception for up to three years, with some evidence supporting efficacy up to five years. Etonogestrel works by binding with high affinity to progesterone receptors in target organs such as the female reproductive tract, mammary gland, hypothalamus, and pituitary. This binding suppresses ovulation by inhibiting the release of luteinizing hormone (LH), increases cervical mucus viscosity to hinder sperm passage, and alters the endometrial lining to prevent implantation of a fertilized egg. Etonogestrel does not have significant affinity for estrogen receptors[1][6][7]. The drug is also used in combination with ethinylestradiol in contraceptive vaginal rings (e.g., NuvaRing). Developed originally by Organon (now part of Merck), it remains one of the most effective forms of birth control[1][6].

Brand names

ImplanonNexplanon

Other names

3-keto-desogestrel