If the ultrasound report indicates that the yolk sac appears to be present after the pregnancy, it means that there is yolk sac-like tissue inside the pregnancy sac. Because the menopause is too short, the yolk sac has not yet grown significantly, and the fetal heart and fetal buds cannot be seen at this time. As long as the yolk sac, fetal heart and fetal buds can grow normally after the ultrasound, it means that there is no abnormality in the embryo and the pregnancy can continue. If the yolk sac is still not visible after 1 week, a blood HCG and progesterone test should be performed to rule out the possibility of embryonic abortion or ectopic pregnancy. If a yolk sac is present, the ultrasound should be repeated in 7-10 days. Normally, there should be fetal buds and fetal heartbeats. Only the presence of fetal buds and fetal heartbeats can be diagnosed as live intrauterine fetus.