EARLY DETECTION OF IMPLANTATION USING A RADIOIMMUNOASSAY SPECIFIC FOR HUMAN CHORIONIC GONADOTROPIN

Abstract
Serial serum levels were obtained from women who were being treated with HMG or were receiving donor insemination. hCG levels were measured by a radioimmunoassay using antiserum specific for the B subunit of hCG. Serum levels of hCG could be detected as early as 9 days following probable ovulation. There did not seem to be any significant differences in the measurement of early chorionic activity following induced or spontaneous ovulation.