RT Journal Article SR Electronic T1 EFFECTS OF ESTRIN AND OTHER HORMONES UPON PREGNANCY JF Journal of Pharmacology and Experimental Therapeutics JO J Pharmacol Exp Ther FD American Society for Pharmacology and Experimental Therapeutics SP 146 OP 161 VO 49 IS 2 A1 F. E. D'AMOUR A1 MARIE C. D'AMOUR A1 R. G. GUSTAVSON YR 1933 UL http://jpet.aspetjournals.org/content/49/2/146.abstract AB Some 350 rats were bred and injected with estrin alone, or in combination with other hormones in varying dosages and at various [See table in the PDF file] times during the gestation period. Pregnancy was invariably prevented or terminated by the injections stated in table 10. We conclude that estrin, in appropriate dosages will invariably terminate pregnancy if injection is commenced by the tenth day, and that, in the dosages used, none of the hormones employed can overcome the effect. Histological study of the uteri disclosed some abnormalities which are being further investigated. Incidental findings worthy of note are: 1. Estrin in dosages of 50 rat units per day for the first ten days and in dosages of 200 rat units per day for the fifteenth to the twenty-fifth day also prevents pregnancy in the rabbit. 2. Injections of 50 mgm. per day of corpus luteum hormone alone give a much higher percentage of fertility than occurs normally.