Table 1.

Classification of progestogens

Classification	Progestogen
Natural	Progesterone
Synthetic	Progestins
	A. Structurally related to progesterone
	1. Pregnane derivatives
	a. acetylated (also called 17-hydroxyprogesterone derivatives): medroxyprogesterone acetate, megestrol acetate, cyproterone acetate, chlormadinone acetate
	b. nonacetylated: dydrogesterone, medrogestone
	2. 19-norpregnane derivatives (also called 19-norprogesterone derivatives)
	a. acetylated: nomegestrol acetate, nestorone
	b. nonacetylated: demegestone, trimegestone, promegestone
	B. Structurally related to testosterone (also called 19-nortestosterone derivatives)
	1. ethinylated:
	a. estranes: norethindrone (also called norethisterone), norethindrone acetate, norethynodrel, lynestrenol, ethynodiol diacetate
	b. 18-ethylgonanes: levonorgestrel, norgestrel, desogestrel, gestodene, norgestimate
	2. nonethinylated: dienogest, drospirenone