Dydrogesterone is a synthetic progestogen that has no estrogenic, androgenic, glucocorticoid, or anabolic effects, although it is an agonist of progesterone receptors (EC50 = 12.3 nM) and an antagonist of androgen, mineralocorticoid, and glucocorticoid receptors (IC50s = 28.6, 82.7, and 363 nM, respectively).Dydrogesterone protects against sound stress-induced abortion in mice when administered at a dose of 1.25 mg per animal prior to the stressor on day five of pregnancy.Formulations containing dydrogesterone have been used in hormone replacement therapy, in the treatment of menstrual disorders, and to prevent miscarriage.