Most of the sudden lightening of pregnancy vomiting in early pregnancy is a normal phenomenon, and in a few cases, fetal arrest occurs. The time and severity of pregnancy reaction varies from person to person, some pregnant women have more intense nausea and vomiting, which last longer, while others show it for a few days. If the development of the embryo is normal on ultrasound, the fetal bud and primitive heart tube pulsation appear on schedule, and there is no abdominal pain or vaginal bleeding, the pregnant woman should not be nervous. If the pregnancy vomiting decreases, the gestational sac does not continue to differentiate and develop, and the fetal buds and heartbeat do not appear on schedule, the diagnosis is fetal abortion, and a timely operation to remove the uterus is required.