[The early pregnancy factor (EPF) as an early marker of disorders in pregnancy]

The early pregnancy factor (EPF) seems to be very helpful in clinical applications such as early detection of pregnancy, differential diagnosis of failure of fertilization or implementation and prognosis of a fertilized ovum. Our purpose was to investigate the diagnostic value of single and serial measurement of EPF, especially in the differential diagnosis of abortion and extrauterine pregnancy. Women with a history of 6-16 weeks amenorrhoea with/without vaginal bleeding were included in the prospective study. The EPF-test system was carried out by means of the rosette inhibition method. EPF proved to be always positive in normal pregnant women and always negative in nonpregnant controls. In case of threatened abortion the prognosis was good, when the EPF values were positive, and poor when they became negative. Patients suffering from spontaneous and missed abortion mostly showed negative EPF-values. This was also true in ectopic pregnancies. The sensitivity and specificity of EPF-test system were 83%. The positive predictive value was observed to be 54% and the negative predictive value 95%. The EPF as an early embryonic signal may be a suitable parameter for the clinical use detecting pregnancy disturbances very early.