Abstract: Serum HCG was determined by RIA in 50 normal women, 75 early pregnancy, 62 middle pregnancy, 69 ectopic pregnancy, 9 dead fetal pregnancy, 15 hydatidiform mole, 2 chorioepithelioma and 4 embroy carcinoma of testis. The numerical values were 24～32, 32 569～61 263, 14 873～25 562, 1 917～3 607, 902～2 916, 119 234～505 359 IU/L (95% Fiducial limits) respectively. There was a great significance between each two groups statisticly(p<0.01) except between ectopic pregnacy and dead fetal pregnacy groups(p<0.05). The change of serum HCG was also analyzed druing treatment in chorioepithelioma, hydatidiform mole and embryoearcinoma of testis. The study indicates that serun HCG and sis could be useful for the diagnosis, differential diagnosis and assessment of therapeutic effect these diseases.

Key words: radioimmunoassay (RIA), human chorionic gonadotropin (HCG), hydatidiform mole, Chorioepithelioma, embroy carcinoma