Family members who do not study medicine do not understand why a newborn baby has hemolysis? They couldn’t figure out why there was a blood type mismatch? They had never heard of a blood type test before marriage, so could they not get married if their blood type was not compatible? What kind of blood type is “compatible”? I believe many people have the same question, let us read this article with questions today, I believe you will be enlightened.
Newborn hemolysis is often due to the mother and child blood type incompatibility
Maternal and fetal blood group incompatibility is a homozygous immune disease between the pregnant woman and the fetus due to blood group incompatibility, which occurs during the fetal and neonatal periods and is an important cause of fetal neonatal hemolytic disease. Maternal and child blood group incompatibility is divided into ABO blood group incompatibility and RH blood group incompatibility.
Why are maternal and fetal blood types incompatible?
It is known that half of the fetus’ genes come from the mother and half from the father. The antigens inherited from the father’s red blood cells, which are lacking in the mother’s blood group, can, under certain circumstances, enter the mother’s body through the placenta and stimulate the production of the corresponding immune antibodies. In the event of another pregnancy, the antibodies may enter the fetus through the placenta and combine with the corresponding antigens on the fetal red blood cells to cause agglutination and destruction, resulting in fetal hemolysis.
When the pregnant woman is type “O” and the husband is type “A”, “B” or “AB”, the blood type inherited by the fetus from the father enters the mother as an antigen, stimulating the mother to produce special anti-A or anti-B antibodies, which in turn can return to the fetus through the placenta and destroy the fetal red blood cells, causing fetal hemolysis to occur.
Because substances similar to A(B) antigens are widely available in nature (plants, parasites, vaccinations), etc., which can also produce anti-A(B) IgG antibodies upon contact, 50% of neonatal ABO hemolysis occurs in the first birth.
The reasoning behind Rh blood group incompatibility is similar to this. When the Rh blood group differs between the couple, i.e. the pregnant woman is Rh negative and the husband is Rh positive, and the pregnant fetus is Rh positive, the anti-Rh antibodies can enter the fetus through the placenta and cause fetal hemolysis due to pregnancy, blood transfusion and other circumstances.
Rh antigen is highly specific and only exists on Rh-positive red blood cells. During normal pregnancy, most of the fetal blood is less than 0.1 ml in the maternal circulation through the placenta, so the first child often has very little disease due to insufficient antibodies. However, if the mother has had a transfusion of RH-positive blood before the pregnancy, the body has produced RH antibodies and RH hemolysis may occur in the first child.
The Rh-negative population is small, so the occurrence of Rh hemolysis is uncommon. However, Rh-negative women should be very careful not to have abortions at will, otherwise their bodies may produce anti-Rh antibodies, and once they are pregnant again, fetal and neonatal hemolysis may occur.
Hazards of maternal and child blood group incompatibility
In serious cases, it may lead to miscarriage, stillbirth or newborns with different degrees of hemolytic anemia or jaundice, resulting in sequelae such as mental retardation, neurological and motor disorders.
The main two types of maternal and child blood group incompatibility are ABO and Rh, and the main cause of hemolysis in newborns is ABO blood group incompatibility, which is more common, less harmful and often neglected; Rh blood group incompatibility is rare, but the disease is serious.
Monitoring of maternal and child blood group incompatibility
During pregnancy, blood should be drawn periodically to determine the potency of ABO and RH antibodies in the blood of pregnant women with possible blood group incompatibility. Measurements should be done every 2 weeks from 28 to 32 weeks of gestation and weekly after 32 weeks.
It is recommended that Rh-negative pregnant women be tested prenatally for the presence of antibodies against Rh-positive blood and that anti-D immunoglobulin be administered at 28 weeks of pregnancy and within 72 hours after the birth of the first Rh-positive baby to prevent the development of antibodies in pregnant women.
For more serious pregnancies, ultrasound is also needed to monitor fetal growth and development, to detect fetal hemolysis and anemia in time and to cooperate with treatment.
What should be done for hemolysis in newborns?
Most children with ABO blood group incompatibility can recover spontaneously, but in severe cases, pathological jaundice or kernicterus may occur. If the jaundice is severe, the baby should be referred to the neonatal unit for medication or blue light therapy.
After reading the above, many women may be very worried and eager to go to the hospital to check their blood type. Once they find out that their blood type is different from that of their husbands, they are very worried about the occurrence of neonatal hemolysis in the fetus after pregnancy.
Therefore, it does not mean that men and women with “blood type incompatibility” cannot get married, but it is recommended that all fathers and mothers-to-be do a full prenatal checkup before pregnancy, including the determination of blood type, and if there is a possibility of mother and child blood type incompatibility, strengthen antibody monitoring during pregnancy, and strengthen monitoring after the birth of the newborn, and timely treatment and treatment of any abnormality, generally speaking, there is not much harm.