Embryo arrest, also known as missed abortion, refers to the condition in early pregnancy where, due to congenital developmental defects in the gestational sac or other influencing factors, natural development does not occur, resulting in the absence of a fetal heartbeat. Once embryo arrest has been diagnosed, the embryo generally does not continue to grow, because embryo arrest means that the gestational sac has died and is gradually decaying. If a subsequent ultrasound check reveals that the embryo may have grown slightly since the previous examination, this should not be considered as growth continuation of the embryo, but rather attributed to measurement error. Therefore, once embryo arrest is detected and meets diagnostic criteria, timely re-examination may show some lengthening of the embryo. However, in the absence of a fetal heartbeat, it still needs to be treated as embryo arrest, and an abortion procedure should be promptly performed.