If there is no fetal heart after pregnancy, the fetus is dead. If it is before 20 weeks of pregnancy it is called fetal abortion and after 20 weeks of pregnancy it is called stillbirth. There are many causes of fetal abortion or stillbirth, as follows: 1, common such as chromosomal abnormalities, chromosomal abnormalities, the fetus is usually early on fetal abortion, because humans are eugenic reasons, very early embryos stop developing; 2, uterine malformations, such as uterine longitudinal septum, stump horn uterus, because the embryo does not have enough blood supply after bed, can cause fetal abortion; 3, placental factors, such as placenta abruptio or placenta praevia The fetus can die due to hypoxia and asphyxia; 4. Viral infection can also affect the development of the embryo and lead to the death of the embryo; 5. Pregnant women’s comorbidities and complications, such as diabetes and hypertension, can also cause the death of the embryo or fetus, as well as exposure to harmful substances during pregnancy, radioactive substances, such as home decoration, high formaldehyde content, can also cause fetal abortion, or after 20 weeks of pregnancy The death of the embryo, followed by exposure to radioactive substances, can also cause fetal abortion or embryo death. If the embryo is found to be dead during the examination, it should be treated promptly, because the death of the embryo can cause maternal coagulation dysfunction after a large amount of harmful substances enter the mother’s body, resulting in diffuse intravascular coagulation and postpartum hemorrhage. Therefore, if fetal abortion or embryo death is detected, the pregnancy should be terminated in time.