The success rate of having a yolk sac at 25 days after the transfer is around 80%-90%, and it is necessary to make sure that there is the development of germ and fetal heart in the uterine cavity to be able to indicate the success of the transfer. The presence of yolk sacs after 25 days of transplantation is normal and indicates that the success rate after transplantation is relatively high, but it can not be diagnosed as a successful transplantation, and it is necessary to go to the hospital for ultrasound in a few days to make sure that there are embryonic buds and fetal heart development in the uterine cavity, which proves that the uterus is a live fetus, and then it can indicate that the transplantation has been successful. If only the yolk sac appears after transplantation, and there is no germ and original cardiovascular beat, we should consider fetal arrest, which indicates that the transplantation has failed, and the pregnancy should be terminated in time to deal with it, and the pregnancy should not be continued. After the transplantation to go to the hospital to check to be able to understand the success rate of the transplantation, abnormalities need to be timely diagnosis and treatment, so as not to cause danger.