HCG is too low if there is no problem with the fetus can be taken, if combined with vaginal bleeding or abdominal pain and other symptoms, may not be taken. 1. HCG is a glycoprotein hormone that changes with the cycle of pregnancy, reaching its peak at 8-10 weeks of gestation, and then dropping rapidly. When it reaches the middle and late stages of pregnancy, the HCG value is only 10% of the peak value, which is a normal physiological phenomenon, and the fetus can be taken. 2. Can not be: in early pregnancy, fetal growth and development or fetal arrest, this situation trophoblast cells can not normal secretion of human chorionic gonadotropin, HCG value will be very low, this situation if the fetus has fetal arrest or growth and development abnormalities, the chances of having a baby are very small. In addition, if the embryo has been deposited outside the uterus, resulting in ectopic pregnancy, it will not be able to secrete human chorionic gonadotropin normally, which will be manifested by a very low HCG value, and the fetus will not be viable in this case. It is not possible to determine whether the fetus is viable on the basis of low HCG, it is necessary to analyze the specific situation and communicate with the doctor in time to clarify the reasons for the correct treatment.