Progestogens (progestins)
Progesterone and synthetic relatives. They protect the uterine lining during estrogen therapy, treat bleeding disorders and prevent pregnancy.
What they are
Natural progesterone and synthetic progestins (derivatives of progesterone, such as medroxyprogesterone acetate, or of 19-nortestosterone, such as norethisterone and levonorgestrel). They are used in menopausal hormone therapy for women with a uterus, for secondary amenorrhoea, abnormal uterine bleeding and endometriosis, and as contraceptives (pills, injections, implants, intrauterine systems). Some have androgenic, glucocorticoid or antimineralocorticoid side effects depending on the molecule.
Mechanism of action
They bind the progesterone receptor, a nuclear receptor, in the uterus, breast, cervix and hypothalamus-pituitary. In the endometrium they turn the estrogen-primed proliferative lining into a secretory one and limit its growth, so unopposed estrogen no longer drives hyperplasia or cancer; withdrawal causes a bleed. At the hypothalamus and pituitary they cut LH and FSH secretion and block ovulation, and they thicken cervical mucus.
Target: Progesterone receptor (PGR), a nuclear receptor
Drugs in this class
- Medroxyprogesterone acetateA synthetic progestin: a contraceptive injection every three months, and tablets for bleeding disorders and to protect…Progesterone receptor (PR), a nuclear receptor
- NorethisteroneA 19-nortestosterone progestin used for endometriosis, abnormal bleeding and amenorrhoea, in contraceptive pills and…Progesterone receptor (PR), a nuclear receptor
- ProgesteroneThe natural ovarian hormone, as oral capsules, used with estrogen to protect the uterus after menopause and to bring…Progesterone receptor (PR), a nuclear receptor
- MegestrolA synthetic progestogen taken by mouth. It treats some breast and endometrial cancers and stimulates appetite in…Progesterone receptor (PGR); it also has glucocorticoid activity
Others in the class
- Levonorgestrel
- Desogestrel
- Etonogestrel
- Dienogest
- Drospirenone
- Megestrol acetate
Test yourself
Think of the answer, then tap the question to see it.
Why is a progestogen added to estrogen in a woman with a uterus?
Estrogen alone stimulates the endometrium and raises the risk of hyperplasia and endometrial cancer; the progestogen makes the lining secretory and limits its growth.
How do progestin-only contraceptives prevent pregnancy?
They suppress LH and FSH and so ovulation (strongly with the depot injection), thicken cervical mucus and thin the endometrium.
What bone effect is linked to depot medroxyprogesterone acetate?
Loss of bone mineral density that increases with duration and may not fully recover.
Educational content on how drugs work; not a prescribing guide and no substitute for a health professional's advice. No doses are given.
Sources: DailyMed - MEDROXYPROGESTERONE ACETATE tablet (DailyMed (U.S. National Library of Medicine), 2026); DailyMed - PROGESTERONE capsule (DailyMed (U.S. National Library of Medicine), 2026); DailyMed - MEDROXYPROGESTERONE ACETATE injection, suspension (DailyMed (U.S. National Library of Medicine), 2026).
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Representative model, for educational purposes only.