The changes of blood β-HCG after medical abortion plus curettage at 7 to 25 weeks′ gestation

Objective To explore the changes of plasma β-human chorionic gonadotropin(β-HCG) concentrations before and after medical abortion plus curettage at 7 to 25 weeks′ gestation. Methods 160 gravidas who wanted to terminate pregnancies were divided into group A (gestational age ≤8 weeks, n=48), group B (gestational age 8 but ≤12 weeks, n=62), and group C (gestational age 12 but ≤25 weeks, n=50). The same medical abortion plus uterine curettage was performed in all the gravidas and plasma β-HCG levels were detected one day before, 24 and 48 hours following use of mifepristone, and at days 1, 7, 14, and 21 after abortion and curettage. Results The average baseline value of β-HCG was (95 930 ± 22 310) mIU/mL in group A, (143 640 ± 35 730) mIU/mL in group B, and (47 610 ± 31 760) mIU/mL in group C. The β-HCG level was decreased by 6.94%, 2.90%, and 14.25% at day 2 after use of mifepristone, by 75.38%, 68.20%, and 83.90% at day 1 after abortion, by 99.72%, 98.96%, and 99.46% at day 7, respectively. It declined to less than 10 mIU/mL in all groups at day 21. Conclusions The baseline levels of β-HCG are different at different gestational ages, with a high level at 8 to 12 weeks′ gestation. No significant decrease in β-HCG levels occurs after use of mifepristone. The amplitude of decline in β-HCG is greatest at day 1 after medical abortion, the lower the baseline, the greater the amplitude of decline. β-HCG level decreases slowly from day 7 and returns to normal at day 21.