A woman’s pregnancy is calculated from the first day of her last menstrual period, three weeks of pregnancy which is 21 days, and bleeding within this time period, as long as three cases are considered. Firstly, bleeding from the fertilized egg, because it takes about 16 days for the follicle to develop, plus about 5 days for the fertilized egg to just take hold. A small amount of bleeding can occur during this period of time, and as long as care is taken, no special treatment can be required. Secondly, the bleeding should be considered to be caused by abnormal pregnancy, for example, the patient is bleeding due to preterm miscarriage or ectopic pregnancy. However, because the time is too short, the ultrasound cannot yet see the location of the gestational sac’s implantation, and can only make a preliminary judgment by monitoring blood progesterone and HCG. It is not recommended to perform a special procedure until the location of the gestational sac is found. Thirdly, to consider bleeding from other parts, such as bleeding caused by cervical lesions or localized vaginal lesions, gynecological internal examination ultrasound and other tests are needed for identification.