Norgestrel was patented in 1961 and came into medical use, specifically in birth control pills, in 1966.[9][10][11] It was subsequently introduced for use in menopausal hormone therapy as well.[7] Norgestrel is sometimes referred to as a "second-generation" progestin.[12] It is marketed widely throughout the world.[7][4] Norgestrel is available as a generic medication.[13] In 2021, the version with ethinylestradiol was the 227th most commonly prescribed medication in the United States, with more than 1million prescriptions.[14][15] In July 2023, the U.S. Food and Drug Administration (FDA) approved norgestrel for over-the-counter sale.[2]
Notes: Values are percentages (%). Reference ligands (100%) were promegestone for the PRTooltip progesterone receptor, metribolone (a = mibolerone) for the ARTooltip androgen receptor, E2 for the ERTooltip estrogen receptor, DEXATooltip dexamethasone for the GRTooltip glucocorticoid receptor, aldosterone for the MRTooltip mineralocorticoid receptor, DHTTooltip dihydrotestosterone for SHBGTooltip sex hormone-binding globulin, and cortisol for CBGTooltip Corticosteroid-binding globulin. Sources: See template.
The ovulation-inhibiting dose of norgestrel appears to be greater than 75μg/day, as ovulation occurred in 50 to 75% of cycles with this dosage of norgestrel in studies.[17] The ovulation-inhibiting dosage of levonorgestrel, which is twice as potent as norgestrel, is approximately 50 to 60μg/day.[6][18][17] One review lists the ovulation-inhibiting dose of norgestrel as 100μg/day.[19] The endometrial transformation dose of norgestrel is listed as 12mg per cycle and the menstrual delay test dose of norgestrel is listed as 0.5 to 2mg/day.[19][20]
Norgestrel, also known as rac-13-ethyl-17α-ethynyl-19-nortestosterone or as rac-13-ethyl-17α-ethynylestr-4-en-17β-ol-3-one, is a syntheticestranesteroid and a derivative of testosterone.[3][4] It is a racemic mixture of stereoisomers dextronorgestrel (the C13α isomer; l-norgestrel, L-norgestrel, or (+)-norgestrel) and levonorgestrel (the C13β isomer; d-norgestrel, D-norgestrel, or (–)-norgestrel), the former of which is inactive (making norgestrel exactly half as potent as levonorgestrel).[22][23] Norgestrel is more specifically a derivative of norethisterone (17α-ethynyl-19-nortestosterone) and is a member of the gonane (18-methylestrane) subgroup of the 19-nortestosterone family of progestins.[24]
Norgestrel was first introduced, as a birth control pill in combination with ethinylestradiol, under the brand name Eugynon in Germany in 1966.[9][10] It was subsequently marketed as a combined birth control pill with ethinylestradiol in the United States under the brand name Ovral in 1968, and was marketed in many other countries as well.[25][26][7]
The contraceptive efficacy of norgestrel was established in the U.S. with the original approval for prescription use in 1973.[2]
^ abOrtiz-Gómez T, Santesmases MJ (22 April 2016). Gendered Drugs and Medicine: Historical and Socio-Cultural Perspectives. Taylor & Francis. pp. 175–. ISBN978-1-317-12981-3. The 1966 marketing campaign for Schering's second contraceptive, Eugynon, [...] (Schering AG Berline 1966, 11). [...] In 1970 [Schering] had already conducted an opinion poll among doctors in the run up to the marketing campaign for the newly introduced Neogynon. [...]
^ abEndrikat J, Gerlinger C, Richard S, Rosenbaum P, Düsterberg B (December 2011). "Ovulation inhibition doses of progestins: a systematic review of the available literature and of marketed preparations worldwide". Contraception. 84 (6): 549–57. doi:10.1016/j.contraception.2011.04.009. PMID22078182.
^Schindler AE, Campagnoli C, Druckmann R, Huber J, Pasqualini JR, Schweppe KW, et al. (December 2003). "Classification and pharmacology of progestins". Maturitas. 46 (Suppl 1): S7–S16. doi:10.1016/j.maturitas.2003.09.014. PMID14670641.