. "Catalysis of the reaction: NAD(P)+ + 17-alpha,20-alpha-dihydroxypregn-4-en-3-one = NAD(P)H + H+ + 17-alpha-hydroxyprogesterone." . . "20alpha-HSD" . "20alpha-hydroxysteroid dehydrogenase" . "17-alpha,20-alpha-dihydroxypregn-4-en-3-one dehydrogenase activity" . "20alpha-HSDH" . "20alpha-hydroxy steroid dehydrogenase activity" . "20alpha-hydroxysteroid:NAD(P)+ 20-oxidoreductase activity" . . .