Fetal abortion can also occur after 12 weeks of pregnancy, but it is less common than before 12 weeks of pregnancy. Fetal abortion is a miscarriage or stillbirth in which the embryo stops developing for some reason early in the pregnancy and the fetal morphology or germ in the uterus is incomplete on ultrasound examination, with no fetal heartbeat. This condition is mostly related to abnormal development of the embryo itself, such as abnormal number and structure of chromosomes, abnormal genetic material carried by sperm, etc. In addition, maternal luteal insufficiency, too thick or too thin endometrium, uterine adhesions, reproductive tract infections, drugs, and adverse environmental factors can lead to fetal abortion in early pregnancy. Before 12 weeks of pregnancy, it is easy to be affected by various factors and cause fetal abortion. After 12 weeks of pregnancy, the pregnancy is smoother and the probability of fetal abortion will be reduced, but if the risk factors that cause fetal abortion still exist, the pregnant woman may still have fetal abortion. Patients will usually be scheduled for an NT test at around 12 weeks of pregnancy, which can detect any problems with the embryo in time. During pregnancy, pregnant women should strengthen pregnancy care, have regular obstetric checkups, monitor the growth and development of the fetus, avoid exposure to chemical substances or drug abuse, and pay attention to avoid being in an environment with radioactive substances, engage in appropriate outdoor activities to prevent the occurrence of viral infections, and correct bad habits such as smoking and alcohol abuse, which can generally prevent the occurrence of fetal abortion.