If the yolk sac and the embryo germ are not found by ultrasound examination after pregnancy, there may be several clinical reasons: firstly, if the pregnancy is relatively short, the development of the embryo is a gradual process, so the yolk sac and the embryo germ have not been found during this period is also a normal phenomenon. With the further development of pregnancy, the yolk sac will be found after 5 days or 1 week of ultrasound examination. Secondly, because of the empty sac formed by the cessation of development of the embryo, if the menstrual cycle is usually regular, the cycle is 28-30 days, if the yolk sac is still not seen by ultrasound examination on the 42nd day after menopause, no embryonic buds can be seen, but only an empty gestational sac can be seen, it is possible that the development of the embryo has already ceased, it is recommended to combine with the results of the blood HCG monitoring and the results of progesterone examination to analyze and terminate the pregnancy if necessary. If necessary, terminate the pregnancy.