The first examination has fetal heartbeat and the second one has no fetal heartbeat. Fetal arrest may be caused by embryonic factors, maternal factors, father’s factors, environmental factors and so on. 1. Embryonic factors: chromosomal abnormalities in the fetus will affect the normal development of the embryo, resulting in fetal arrest. 2. Maternal factors: when the mother is infected with pathogenic bacteria, such as rubella virus, herpes simplex virus and so on, it will lead to embryonic infection, which will cause fetal arrest; the mother has some chronic diseases such as diabetes, high blood pressure, nephritis and so on, which will affect the health of the mother and the embryo, leading to abnormal development of the embryo, resulting in fetal arrest. In addition, the mother’s uterine development is abnormal or have uterine adhesions, endocrine disorders, etc., these factors are not conducive to the development of the fetus, resulting in fetal ejection. 3. Father factors: poor quality of male sperm will affect the normal development of the embryo, resulting in fetal arrest. 4. Environmental factors: frequent exposure to X-rays or the surrounding environment has some stimulating chemicals, this situation is not conducive to the development of the embryo, the emergence of abortion. There may be other reasons for the absence of fetal heartbeat after the first examination. It is recommended to go to the hospital in time, complete the examination to clarify the cause of the disease, and then give targeted treatment or therapy under the guidance of the doctor.