ALLYLESTRENOL, A PREGNANCY MAINTAINING ORAL GESTAGEN

Abstract

ABSTRACT In the search for a pregnancy maintaining steroid allylestrenol has been found orally active in the Clauberg assay, the mouse deciduoma test and in maintaining pregnancy in spayed rats. It has been shown to be practically devoid of androgenic, oestrogenic and gonad- and adrenal-inhibiting properties; no impairment of pregnancy and no influence on the external genitalia of foetuses were observed. Some antioestrogenic activity is present. In chronic toxicity studies in rats and dogs no signs of general toxicity were observed. Allylestrenol can thus be considered as a pure and complete oral gestagen.