The gestational sac can usually be seen on ultrasound examination at 5-6 weeks of menopause, while the fetal heartbeat and fetal bud can be seen at 6-7 weeks of menstruation. If the gestational sac is larger than 2 cm and no fetal heartbeat or fetal bud is seen, it is considered to be a sign of an empty gestational sac. Blood progesterone and blood HCG tests should be performed and the ultrasound should be repeated in 1 week to check the fetal heartbeat and fetal bud. If the test result indicates that the fetal heartbeat and fetal bud are still not seen, the possibility of embryonic arrest is high. There are many causes of embryonic arrest, such as chromosomal and genetic abnormalities of the embryo, serious medical conditions of the pregnant woman (hypertension, diabetes, hyperthyroidism, hypothyroidism, etc.) or exposure of the pregnant woman to toxic substances and radiation, etc., which can cause the condition of embryonic arrest. When the diagnosis of embryonic arrest is confirmed, it is recommended that the uterus be removed promptly. Before the next pregnancy, a routine preconception checkup is needed to avoid the recurrence of a large gestational sac without a fetal heartbeat.