Among the many causes of miscarriage, blood group incompatibility is also one of the factors. Blood group incompatibility between the mother and the fetus can cause hemolysis and anemia in the mother’s womb, and in severe cases, miscarriage or premature birth, and even death of the newborn. In some fetuses, the large amount of bilirubin produced by hemolysis enters the brain cells and causes toxic lesions in the central nervous cells of the newborn, called nuclear jaundice. The mortality rate of nuclear jaundice is extremely high, and even if it survives, it can affect the mental development and motor ability of the sick child. There are two main types of maternal and infant blood group incompatibility, RH and ABO. When the mother’s blood type is RH negative and the fetus is RH positive, the mother can be sensitized by RH to produce antibodies, which enter the fetus’ blood through the placenta and cause hemolysis. Similarly, when the mother has O blood type and the fetus has A or B blood type, anti-A or anti-B antibodies can be produced in the mother’s body, which can cause hemolysis when they enter the fetus with the blood flow. It can be seen that the mother’s blood type must be RH-negative and the father’s blood type must be RH-positive, and the fetus must be RH-positive to cause fetal RH hemolysis. If the father is RH-positive, the fetus will not get the disease if it is RH-negative. Similarly, in ABO hemolysis, the pregnant woman must be type O, and the fetus may be type A or B only if the husband is type A, B or AB, thus producing hemolysis. Of course, if the father’s blood type is O or A2, the fetus’ blood type may be O or A2, even if the mother’s blood type is O, it will not cause blood group incompatibility. Both RH and ABO blood types have the same consequences and can cause fetal hemolysis, but there are also differences between the two. Firstly, the incidence of RH incompatibility is very low in our population and is particularly rare in Han Chinese, while the incidence of ABO hemolysis is significantly higher, up to 1% in some areas among newborns. Secondly, RH blood group incompatibility generally does not occur in the first child, which is due to the fact that the amount of antibodies produced in the body of the pregnant woman during the first pregnancy is small and not enough to cause fetal morbidity. ABO hemolysis, which is less severe, rarely causes fetal death in utero, but it can be acquired in the first child. With the continuous improvement of medical testing technology, the correct rate of diagnosing blood group incompatibility has been greatly increased. Various methods are available to determine the relevant antibodies in the maternal serum to estimate the prognosis of the fetus. For hemolysis of mother and child due to blood group incompatibility, a combination of Chinese and Western medicine should be used from the beginning of pregnancy under the supervision of medical personnel to reduce the antibodies in the pregnant woman’s body, improve the fetus’ viability, prolong its life in the womb and prevent it from leaving the mother prematurely, i.e. miscarriage or premature birth. The concentration of antibodies in the serum of pregnant women is regularly measured as an objective indicator of termination of pregnancy. In general, when the RH antibodies are more than 1/32 or ABO antibodies are more than 1/512, then induction of labor should be considered to terminate the pregnancy and save the little life. Of course, other medical histories and tests should be taken into account to make the final decision to induce labor. Pregnant women with blood type incompatibility should deliver in a hospital with good medical conditions to avoid asphyxia of the newborn. The newborn should also be monitored by a pediatrician for signs of jaundice or anemia so that treatment can be taken as soon as possible. For the most serious hemolytic children, blood exchange therapy can also be used to give new life to the dying hemolytic children. As for the prevention of habitual abortion due to maternal and child blood group incompatibility, there is no proven method yet. In order to prevent the risk of blood group incompatibility caused by higher and higher antibodies in the blood of pregnant women due to multiple pregnancies, abortion should not be performed several times, especially for some young couples who do not use contraception after marriage and do not want to have children, resulting in multiple abortions. Once you want to have a child, but can no longer keep it. Therefore, avoiding the first abortion can indirectly reduce the chances of blood type incompatibility. Secondly, if the first child has had a stillbirth, stillbirth, neonatal jaundice or congenital brain damage of unknown origin, or if the pregnant woman is over 35 years old, or if the pregnant woman is type O and the husband is type A, B or AB, or if the husband is RH-positive and the wife is RH-negative, the woman should be alert to the occurrence of hemolytic disorders in the mother and child when she becomes pregnant again.