Usually hCG values between 5 and 2000 U/L are in the early stages of pregnancy. hCG, also known as human chorionic gonadotropin, is a glycoprotein hormone produced by gestational trophoblast cells. After the fertilized egg is laid, the trophoblast cells start to produce hCG, which can be measured in the blood one day after laying, and then doubles every day, up to about 0.7 times normal. Half a month after ovulation, hCG can reach 100U/L, and on the 40th day of pregnancy, hCG can normally increase to more than 2000U/L. Therefore, during early pregnancy, the state of hCG doubling is more meaningful for predicting the development of embryo. If the hCG doubling is not good or decreases instead of rising, it usually indicates ectopic pregnancy or inevitable miscarriage. After the rise of hCG is measured in early pregnancy, it should be closely observed and if there is no bleeding and abdominal pain, it can be rechecked once in 5-7 days, and the frequency of rechecking should be increased if there is any abnormal condition.