Threatened miscarriage occurs often and is a serious emotional burden for women. The aim of this work was to study if there is a correlation between the different measured endocrinological (serum free beta-HCG and vascularity, decidual thickness and uteroplacental blood flow) and the occurrence of abortion, and the possibility of such markers to be used as predictors for first trimester abortion. In conclusion, our findings suggest the possibility of using decidual thickness, corpus luteum volume and serum free beta-HCG for the prediction of the prognosis of threatened first trimester abortion.