The vaginal bleeding that occurs just after the pregnancy has been detected cannot be called normal menstruation, but abnormal vaginal bleeding. There are three main possibilities to consider in this case: 1. Biochemical pregnancy: Biochemical pregnancy means that the pregnancy is determined by checking blood or urine HCG. But the ultrasound did not determine the presence of the gestational sac, there is no way to determine whether the pregnancy is intrauterine, or extrauterine pregnancy, the patient has a vaginal bleeding, the amount is relatively large, as the amount of menstruation, after the bleeding is over, the patient’s blood HCG gradually decreased to normal levels.2, preeclampsia or the possibility of miscarriage. If the patient to do ultrasound has been determined to be intrauterine pregnancy, the bleeding is relatively heavy in the case to consider the flow. If the amount of bleeding is relatively small, we should consider preeclampsia, and need to dynamically observe the changes in blood progesterone as well as HCG, and carry out fertility preservation treatment.3, ectopic pregnancy: if the patient’s blood HCG and progesterone are relatively high, but the uterine cavity can not see the gestational sacs, and found outside the uterus in the mass, accompanied by vaginal bleeding, we have to consider the possibility of ectopic pregnancy.