Objective To investigate the clinical viability of pre-eclampsia by measuring the level of ?-HCG in blood,blood calcium,hematocrit(HCT)and the mean arterial blood pressure(mABP).The preventive value of calcium supplement was also evaluated. Methods 356 volunteers'(16th～20th gestational weeks)were measured ?-HCG in blood,blood calcium,HCT,meanwhile mABP from the same patients.If blood ?-HCG≥50 632 IU/L,blood calcium≤2.18 mmol/L,HCT≥0.35 and mABP≥85 mm Hg(1 mm Hg=0.133 kPa),a positive conclusion was made.Women with positive results were randomly divided into test group and control group. Results 71 cases turned out to be positive in this serial test.The positive predictive value was 81.82%,negative predictive value was(97.30%),the sensitivity and specificity were 84.38% and 96.77% respectively.In the study group,the incidence of pre-eclampsia was significantly decreased as compared with the control group(P