The reference value of HCG depends on the specific situation, in normal people without pregnancy, it is between 0 and 5 IU/L. Once the gestational sac implants in the uterus, a large amount of human chorionic gonadotropin will be produced and the value of HCG will increase significantly. The value of HCG can be detected by a blood test around 10 days after conception and will not be lower than 25 IU/L. The longer the pregnancy lasts, the higher the increase will be, reaching a peak between 8 and 10 weeks of pregnancy, with the highest value increasing to tens of thousands or even more than 100,000. The HCG growth value must be doubled every other day to be normal, once the test does not rise but falls, it means that the embryo’s poor development can easily lead to pre-eclampsia and should be treated with birth control.