For women who have undergone medical abortion to terminate pregnancy, their HCG will usually drop to the non-pregnant state within half a month after the medical abortion, so the normal range of HCG 15 days after the medical abortion is usually in the range of 0-5 U/L. Due to the fact that after the medical abortion, the women’s moult tissue exfoliation and the recovery of uterine contraction are different, so the speed of the decline of HCG will be different. Some women may not be able to get a negative HCG 15 days after a medical abortion due to the slower shedding of meconium tissue, but it usually does not exceed 500 U/L or more. If a woman, 15 days after the medical abortion, review blood HCG found more than 500U / L, along with irregular vaginal bleeding, we should consider that it may be incomplete medical abortion caused by abnormalities, must check the ultrasound to make a comprehensive judgment. If indeed the residual tissue in the uterine cavity sludge, more need to perform surgical operation of purging, only after the residue completely discharged HCG can drop to the non-pregnant state.