China
Africa
Explore chapters and articles related to this topic
Progestogen use and breast cancer
Published in Barry G. Wren, Progress in the Management of the Menopause, 2020
As already mentioned above, the progestins prescribed for HRT vary from country to country, and the coprescription of progestins together with estrogens is only a recent phenomenon in most countries. The progestin molecule most often prescribed in the United States remains medroxyprogesterone acetate (MPA), a 170H-progesterone derivative exhibiting some glucocorticoid activity and a partial androgenic effect35,36. In Europe, several combinations of estrogens and progestins have been developed and the progestational molecules are often derivatives of 19-nortestosterone which have lost their main androgenic effect, but still bind to the androgen receptor. These well-known 19-nortestosterone compounds include both the estrane derivatives such as norethisterone, and the gonane category such as norgestrel. Progesterone itself, and its derivatives such as dydrogesterone and the 19-norprogesterone compounds, are also largely prescribed in Europe.
Hormonal and natural contraceptives: a review on efficacy and risks of different methods for an informed choice
Published in Gynecological Endocrinology, 2023
Andrea R. Genazzani, Tiziana Fidecicchi, Domenico Arduini, Andrea Giannini, Tommaso Simoncini
Progestins are classified in categories according to their structural origins. They have been divided in generations according to the time of first synthesis. Among those used in the field of HC, pregnanes (17-hydroxyprogesterone derivatives and 19-norprogesterone derivatives, i.e. chlormadinone acetate) and estranes (testosterone derivatives, i.e. norethindrone, norethynodrel, norethindrone acetate, and ethynodiol diacetate) are considered first generation progestins. Only few of these are still used in HC due to their androgenic properties that cause bothersome side effects, as oily skin, acne, and reduced levels of high density lipoproteins (HDL) [30]. Second-generation progestins are called gonanes and derive from testosterone. This includes some of the most widely used progestins, such as levonorgestrel. Third generation include desogestrel, gestodene, norgestimate/norelgestromin, and etonogestrel. These molecules progressively lose the androgenic activity, acquiring a non-androgenic or an antiandrogenic effect. The newest progestins are the fourth-generation ones, that include nonethylated estranes (i.e. dienogest and drospirenone, a spironolactone derivative) and 19-norprogesterones-derivatives pregnanes (i.e. nomegestrol acetate) [29–31].
Delivery of progestins via the subdermal versus the intrauterine route: comparison of the pharmacology and clinical outcomes
Published in Expert Opinion on Drug Delivery, 2018
Norman D. Goldstuck, Hung P. Le
Gonanes are 19-nor-testosterone derivatives which like all progestins contain a 3-keto group on the C3 position and a double bond between the C4–C5 position on the perhydrocyclopentanophenanthrene (steroid) nuclear structure [9]. Gonanes also have an ethinyl group on the C17α position and an ethyl group on the C13 position. Unlike estrane progestins, gonanes are not biotransformed into estrogens. ENG is the 3-keto derivative of desogestrel which is used in oral contraceptives but is only active after bio-transformation to ENG [10].
The paradigm of norgestimate: a third-generation testosterone-derivative progestin with a peripheral anti-androgenic activity and the lowest risk of venous thromboembolism
Published in Expert Review of Clinical Pharmacology, 2021
Giovanni Grandi, Maria Chiara Del Savio, Fabio Facchinetti
NGM (Figure 1a) is a 19-nortestosterone derivative of the gonane family [1]. NGM is 17-ethylinated, 18-methyl steroid with a 17-position acetate and an oxime at position 3 (Figure 1a). The C-17 acetate group as well as a unique C-3 oxime group inhibit its ability to bind to ARs. Because the C-3-keto group is typical of androgenic compounds, its replacement by the oxime group can contribute to reduce the androgenicity of NGM as compared with norgestrel (NGL) and levonorgestrel (LNG) [6], in addition to other peripheral mechanisms that will be reported later.