During the ultrasound examination, there is no indication of yolk sac and germ, there is a cessation of development. Because the yolk sac and germ is the important system that connects the embryo with the mother, it is also an important indicator to judge whether the fetus is normal or not in the early stage. If the development has stopped at this time, the size of the yolk sac can be judged according to the size of the gestational sac, and it is possible to have a medical abortion. If the size of the sac is less than 2cm, it is possible to have a medical abortion, and after the medical abortion, it is necessary to have a recheck in about 10 days to determine whether there is a clean abortion or not. However, if the embryonic sac is large, and it is more than 2 cm or even 3 cm, it is not recommended to perform a medical abortion. It is recommended to perform direct abortion because the large size of the sac may cause incomplete abortion, risk of hemorrhage, and risk of residual abortion, and risk of evacuation of the uterus.