If the blood HCG is low after pregnancy, it is recommended to perform ultrasound and blood progesterone examination in time to understand the development of the embryo and exclude the possibility of ectopic pregnancy. HCG is serum human chorionic gonadotropin, which can be detected in maternal serum after fertilization of the egg, and reaches its peak at 8-10 weeks of pregnancy. Low blood HCG after pregnancy suggests a possible risk of preeclampsia, abnormal embryonic development, and embryonic abruption. In ectopic pregnancy the embryo is underdeveloped and blood HCG is lower than in intrauterine pregnancy. Combined with the ultrasound and blood progesterone value, if you consider preeclampsia, it should be treated with fetal preservation, you can take oral dextroprogesterone tablets or progesterone injection intramuscularly; if you consider ectopic pregnancy, embryonic sterilizations, hospitalization at the earliest possible time. After the discovery of pregnancy, we should pay attention to rest, reasonable diet, regular hospital obstetric examination, if there is abdominal pain, vaginal bleeding and other uncomfortable at any time to the hospital.