20β-dihydroprogesterone 20β-dihydroprogesterone 20β-dihydroprogesterone (20β-dhp), also known as 20β-hydroxyprogesterone (20β-ohp), is an endogenous metabolite of progesterone which is formed by 20β-hydroxysteroid dehydrogenase (20β-hsd). it is a progestogen similarly to progesterone, with about 20 to 50% of the progestogenic activity of progesterone. it can be converted by 20β-hsd into progesterone in the uterus. the effects of 20β-hsd on the uterus, mammary glands, and in maintaining pregnancy have been studied. the progestogenic activity of 20β-hsd has also been characterized in women. 20β-dihydroprogesterone names iupac name (20r)-20-hydroxypregn-4-en-3-one systematic iupac name (1s,3as,3bs,9ar,9bs,11as)-1--9a,11a-dimethyl-1,2,3,3a,3b,4,5,8,9,9a,9b,10,11,11a-tetradecahydro-7h-cyclopentaphenanthren-7-one other names 20β-dhp; 20β-hydroxyprogesterone; 20β-ohp; 20β-progesterol; 20β-progerol; 20β-hydroxypregn-4-en-3-one; pregn-4-en-20β-ol-3-one identifiers cas number 145-15-3 y 3d model (jsmol) interactive image chebi chebi:36729 chembl chembl2112756 chemspider 8612 echa infocard 100.005.137 pubchem cid 92747 unii 67n4jz6chl y inchi inchi=1s/c21h32o2/c1-13(22)17-6-7-18-16-5-4-14-12-15(23)8-10-20(14,2)19(16)9-11-21(17,18)3/h12-13,16-19,22h,4-11h2,1-3h3/t13-,16+,17-,18+,19+,20+,21-/m1/s1key: rwbruccwzpsbfc-sjokzoansa-n smiles c(1cc21(cc32ccc4=cc(=o)cc34c)c)o properties chemical formula c21h32o2 molar mass 316.485 g/mol except where otherwise noted, data are given for materials in their standard state (at 25 °c , 100 kpa). infobox references