Abstract: | A rapid, sensitive, and specific radioreceptor assay for the determination of human chorionic gonadotropin and luteinizing hormone in plasma is described. Plasma membranes of bovine corpora lutea of early pregnancy, which bind biologically active labeled human chorionic gonadotropin, have been used as receptor. Pregnancy could be detected by assaying the gonadotropin in plasma samples obtained from day 6 to 8 after conception. |