Clinical Application of a Serological Method for the Determination of Human Chorionic Gonadotrophin

IT was early observed that prolonged administration to animals of gonadotrophic hormone from human pregnancy urine was accompanied by gradually diminished effects 1 . This phenomenon has been found to be due to the formation of an antigonadotrophic factor demonstrable only by its capacity to impair the gonadotrophic reaction in rodents 2 . Previous to our earlier report 3 , there had been no demonstration of the antigonadotrophic factor by serological in vitro methods. Precipitating and complement-fixing antibodies had been obtained by immunization of rabbits with gonadotrophic hormone prepared from human pregnancy urine 4,5 . These antibodies, however, were shown to be due to contaminating, antigenically active substances 6 .