After the pregnancy is confirmed, if there is no abdominal pain, vaginal bleeding and other signs of miscarriage, it is recommended to have an ultrasound examination around 6 weeks of pregnancy to clarify the location of the gestational sac and its development, to exclude ectopic pregnancy, and to observe dynamically. In general, if the pregnancy is intrauterine, vaginal ultrasound can detect the gestational sac at about 5 weeks of pregnancy, and the fetal heart and buds may be detected at about 6-7 weeks of pregnancy. If the ultrasound is done through the abdomen, the gestational sac, fetal heart and buds may be detected relatively later. However, if there are signs of abdominal pain, vaginal bleeding and miscarriage, it is necessary to go to the hospital in a timely manner to clarify the location and development of the gestational sac and to rule out ectopic pregnancy. After pregnancy, the specific weeks of pregnancy for ultrasound examination should be decided according to whether the pregnant woman has abdominal pain, vaginal bleeding and other signs of miscarriage.