CASE SHARE: Chen, from Henan Province, has had four children over the past seven years of her marriage, but none of them survived more than a week. Each child developed severe jaundice shortly after birth, and now her fifth child has the same condition. Did you know? The cause of these tragic events is the couple “blood type incompatibility”! Why does “blood type incompatibility” have such a big impact on children? Which blood types are incompatible with each other? Today, we will tell you about blood type! What blood type will my parents give birth to? There are many types of human blood types, and each blood type system is determined by genetic factors. According to the current clinical tests at home and abroad, there are more than 30 types of human blood types! The most common blood type system is the ABO blood type, which is divided into four types: A, B, AB and O; followed by the Rh blood type system. Different blood types of parents, can give birth to which blood type of children? 1, ABO blood type Through the above chart, you can summarize the law of so many points: (1) If both parents are O blood, then the child born is certainly O blood; (2) If the parents are A + B type, then the child born A, B, O, AB possibilities are there. 2, Rh blood type Our red blood cells not only have A, B antigen, but also may have Rh factor: red blood cells containing Rh factor is called Rh (+) that is Rh-positive, does not contain Rh factor is called Rh (-) that is Rh-negative. By statistics, the vast majority of Chinese Han Chinese red blood cells contain Rh factor, Rh-positive blood type accounts for about 99.7% of the population; Rh-negative blood type of the population in our country is relatively small, so Rh-negative blood type is also known as “panda blood”, mainly in the ethnic minorities, the Hmong Rh-negative people as much as 12.3%, the Tatar ethnic group, accounting for 15.8%; Rh-negative blood type is also known as “panda blood”. Rh-negative blood accounts for 15.8%; Rh-negative blood in Europe and the United States accounted for about 15% of white people. So how is Rh inherited? Our genes come from both parents and appear in pairs. We use Rh to represent the dominant gene and i to represent the recessive gene, then: Rh.Rh means Rh-positive, Rh.i also means Rh-positive, and i.i is Rh-negative. If a couple is Rh-positive, then they have three genes, Rh.Rh + Rh.Rh, Rh.Rh + Rh.i, and Rh.i + Rh.i. If both genes are dominant ( Rh.Rh), then they have a child who is Rh-positive as well: If a couple is Rh-positive but one of the partners has a recessive gene, then all of their children are Rh-positive as well. If both partners are Rh-positive, but one partner has a recessive gene, there is a 1 in 4 chance that their child will be Rh-negative: If one partner is Rh-positive and the other partner is Rh-negative, there are two possibilities for their child. If one spouse is Rh-positive and the other is Rh-negative, then there are two possibilities for their child to be Rh-negative. Why does “blood group incompatibility” occur? As we all know, if the blood type is different during a blood transfusion, the two different types of blood will “fight” in the body and cause serious consequences, so it is necessary to do a blood type identification before the transfusion. However, many people do not know, if the parents and the fetus blood type is not compatible, the mother’s body antibodies will enter the baby’s body through the placenta, recognizing the baby’s body on the red blood cells specific antigen, will go to the attack on the destruction of red blood cells, resulting in hemolysis of the baby. 1, ABO blood type incompatibility There is a common sense to understand: A blood type people, red blood cells on the antigen A, plasma is the existence of anti-B; B blood type people, red blood cells on the antigen B, plasma is the existence of anti-A; O blood type people, red blood cells on the antigen, plasma is the existence of anti-A, anti-B; AB blood type people, red blood cells on the antigen A, antigen B, plasma is the absence of antibodies. Therefore, mothers-to-be with blood type O should be especially vigilant because anti-A and anti-B are present in the plasma of people with blood type O. When the fetus has blood type A, anti-A can enter the body of the fetus through the placenta and coagulate with the antigen A on the erythrocytes, thus leading to hemolysis. Similarly, hemolysis can be caused if the mother is type O and the fetus is type B or AB. This is how ABO hemolytic disease occurs. When you go for a maternity checkup, if the mother-to-be has type O blood, the doctor will ask her husband for his blood type or simply ask him to check his blood type as well. If the husband is type A, B or AB, there is a good chance that the fetus will not have the same blood type as the mother. Although the percentage of ABO blood group incompatibility between mothers and babies is as high as 15%, pregnant mothers do not need to worry too much, the vast majority of hemolysis does not occur, and even if it does, the symptoms are very mild, just a little more severe than normal jaundice of newborns, a little bit of blue light can be. Only a very few cases of severe anemia and hyperbilirubinemia, requiring blood transfusion. 2, Rh blood group incompatibility Compared with ABO hemolysis, Rh hemolysis is more serious. As we mentioned above, when an Rh-positive man marries an Rh-negative woman, the fetus’ blood type may be Rh-positive or Rh-negative. If the fetus is Rh positive, be careful! If the blood type of the first fetus is Rh-positive, it will stimulate the Rh-negative mother to produce anti-Rh antibodies. If the mother gets pregnant again and gives birth to a second child, and the second child’s blood type is still Rh-positive, the anti-Rh antibodies will pass through the placenta, dissolving and destroying the red blood cells of the fetus and causing hemolysis in the newborn. If a pregnant woman has had a Rh-positive blood transfusion and her body has long been stimulated to produce anti-Rh antibodies, the first Rh-positive fetus will experience neonatal hemolysis. Mother’s antibodies through the placenta into the fetal body, resulting in a large number of red blood cells “blast” lysis, can immediately cause fetal anemia, edema, splenomegaly, congenital heart disease, and even fetal death, miscarriage; if the fetus survives, from the mother’s antibodies will continue to cause hemolysis of the newborn, 24 hours after birth will be severe jaundice, free bilirubin will be passed through the baby’s blood-brain barrier, causing brain tissue damage. Damage. More severely severely jaundiced babies may show early signs of lethargy, hyporesponsiveness, weak sucking, and a diminished cuddle reflex for 12 to 24 hours, and then may develop severe spasms, including convulsions, corns, fever, and apnea. Sequelae such as cerebral palsy, mental retardation, convulsions, weakness of head lifting and salivation may remain after treatment. What should I do if my blood group is incompatible? Couples with Rh blood group incompatibility should ensure that their first child is born. The chances of mother-child blood group incompatibility occurring in the first child are low, so once pregnant, do not abort easily. Otherwise, the more abortions these women have, the higher the chance of mother-infant blood group incompatibility. Moreover, as the age and number of pregnancies of pregnant women increase, their antibody potency will also increase, and the incidence and severity of hemolytic disease in newborns will also increase. If the husband is Rh-positive and the wife is Rh-negative, and the wife has not had any Rh-positive blood transfusions, there is not much problem in having the first child. This is due to the fact that the amount of antibodies produced in the pregnant woman’s body during the first pregnancy is small and not enough to cause fetal morbidity. If the first child is baby Rh positive, then try not to continue to have children, otherwise the second baby if still Rh positive, the fetus in the womb will be serious hemolysis. ABO blood group incompatibility: Not all ABO blood group incompatibility will lead to hemolysis, only very high levels of anti-A and anti-B in the pregnant mother’s body will lead to hemolysis, so the risk of ABO hemolytic disease can be predicted by detecting the level of anti-A and anti-B in the pregnant mother’s body when she is pregnant. The first measurement is usually done in the 4th month of pregnancy and is used as a base level of antibodies. The results are used as a base level of antibodies. Subsequent measurements are taken once a month, half-monthly in the 7th to 8th month of pregnancy, and weekly after the 8th month. If the indicator is high, it can be controlled and stabilized by taking medication. What should I do if I have hemolysis in my newborn? 1.ABO hemolysis Most of the symptoms of ABO hemolytic disease are relatively mild, and newborns with the possibility of ABO hemolysis should have a bilirubin measurement done in the hospital around the seventh day of life (the peak of the onset of jaundice). The high limit for physiologic jaundice is 12.9mg/d. If your baby’s bilirubin is slightly elevated at this level, you can let your child stay indoors in the sun through glass for 1-2 hours twice a day. In order to get full exposure to the sun, let the baby’s head and chest bare, at the same time in order to avoid sunlight irritation of the baby’s eyes, you should try to put on a blindfold for the child. After two days of this sun exposure, return to the hospital for a review. Severe jaundice must be treated with blue light irradiation in the hospital, while the doctor may use medication at his discretion to promote the metabolism of bilirubin and its excretion from the body. 2, Rh hemolysis Rh hemolysis often occurs in the sixth or seventh month of pregnancy, the way to save the child is: wait until the fetus grows to be viable, early labor and delivery (natural delivery or Caesarean section), so that the fetus is less subject to the harmful effects of anti-Rh antibodies. After the birth of a newborn, the first thing to do is to do a blood test, because only Rh-positive newborns will suffer from “Rh hemolytic disease”, while Rh-negative newborns will not be at risk; if the test shows that the newborn has been harmed by the anti-Rh antibodies, it is necessary to use the exchange of blood therapy, that is, with double the newborn individual blood, the newborn’s body of blood all replaced, which can clear the blood, the newborn’s body. This removes some of the bilirubin, antibodies and sensitized red blood cells, inhibits hemolysis and corrects anemia, followed by treatment such as blue light.