 OHPA is of relatively low potency as a progestogen, which may explain its relatively limited use.It is 100-fold less potent than medroxyprogesterone acetate, 400-fold less potent than chlormadinone acetate, and 1,200-fold less potent than cyproterone acetate in animal assays.In terms of producing full progestogenic changes on the endometrium in women, 75 to 100 mg/day oral OHPA is equivalent to 20 mg/day parenteral progesterone, and OHPA is at least twice as potent as oral ethisterone in such regards.