THE FEMALE SEX HORMONE

Abstract

Independently, and almost simultaneously, Loewe 1 and one of us, together with collaborators 2 demonstrated the presence of the female sex hormone in the circulating blood. This observation is the first demonstration by means of a specific and direct test of the presence of a true hormone in the circulation. The test employed is the change from leukocytes to squamous epithelium noted in the vaginal smear of castrated rats and mice. 3 In this short preliminary report, no retails as to method and technic will be given. We have obtained the female sex hormone from the blood specimens by means of lipoid extraction performed under identical conditions by identical methods. The results are sufficiently concordant to be considered quantitative. Blood has been obtained from thirty-eight patients. In some instances, specimens have been taken at intervals of from five to seven days through two monthly cycles from the same patient. From