There are many causes of fetal abortion, and blood type O does not directly affect fetal abortion. If fetal abortion occurs due to blood type O, it may be related to the occurrence of hemolysis. If the mother of the fetus has type O blood and the father has type A, B or AB blood, then the fetus has type A or B blood. Then there is an incompatibility between the blood type of the mother and the fetus, and the antibodies in the mother’s blood enter the fetal blood circulation and destroy the fetal red blood cells, thus affecting the growth and development of the fetus and leading to fetal arrest. Therefore, if risk factors are present, it is necessary to go to the hospital for prenatal blood group serological examination early in the preparation period. If the antibody activity is low, you can prepare for pregnancy with peace of mind. If the antibody activity is high, medication can be used to reduce the antibody activity to ensure normal fetal development. During pregnancy, the blood should be regularly tested for antibodies and the fetus should be closely monitored for the possibility of hemolytic disease. When the newborn is born, early monitoring of bilirubin should be done and phototherapy should be performed in time when the criteria for phototherapy are met. In addition, there are many causes of fetal abortion, which may also be due to abnormal embryo quality, chromosomal abnormalities, etc. It is recommended that couples should undergo chromosome testing, prepare for pregnancy scientifically and maintain a healthy lifestyle.