Human early pregnancy factor: serum concentrations before and after therapeutic abortion in comparison with beta-hCG and an early pregnancy associated protein.

Serum concentrations of the early pregnancy factor (EPF), beta-hCG and the early pregnancy associated protein (EPAP) were measured in 12 patients before and after therapeutic abortion for social-medical reasons. Detection of EPF was performed by the rosette-inhibition assay, beta-hCG quantification by radioimmunoassay and EPAP measurements by rocket immunoelectrophoresis using a monospecific polyclonal rabbit antiserum. The disappearance rate of EPF after termination of pregnancy was closely correlated with the decrease of beta-hCG concentrations (rpbis = 0.71) and loosely correlated with the decrease of EPAP concentrations (rPbis = 0.43). No correlation has been found between hCG and EPAP values.