It is said that there is a widespread saying on the Internet that "men with blood type AB cannot marry women with blood type O", because babies born to mothers with blood type O may suffer from "neonatal ABO hemolysis", resulting in anemia, jaundice and other diseases.
Key points:
When a woman with type O blood combines with a man with other blood types and is pregnant with a baby who is not type O blood, neonatal ABO hemolysis may occur, but the probability is relatively low and there are few serious consequences. Women with type O blood can get married and pregnant with confidence, and it is enough to do a regular prenatal examination.
Verified by: Wan Yi, Zhibei Medical Adult Physician/internationally certified lactation consultant
There is a popular saying on the Internet that "men with blood type AB cannot marry women with blood type O". The reason is that babies born to mothers with blood type O may suffer from "neonatal ABO hemolysis", resulting in anemia, jaundice and other diseases. Is this true? In fact, this is not just a problem for AB men. As long as the mother of type O blood has a baby with non type O blood, there is a risk of "neonatal ABO hemolysis". So how does "neonatal ABO hemolysis" happen? How dangerous is it? Can women with type O blood really not marry men with other blood types?
1、 How does ABO hemolysis occur?
All this has to start with the classification and characteristics of blood types.
In brief, there is a well-known blood group classification method in the population, which divides blood groups into four types, namely, type A, type B, type AB and type O.
Let's start with Type A and Type B. These two blood types are like two countries with deep hatred. It is easy to shoot each other.
In people with type A blood, red blood cells in the body can express A antigen, just like every household in this country has an A flag. Not only that, this country also has a guard team, that is, the "anti B antigen antibody" in the plasma (hereinafter referred to as "anti B"). Once anti B finds type B red blood cells with the flag of "B", it will rush to fight with each other, leading to destruction and elimination of red blood cells. On the contrary, there are also "anti A" in the body of type B blood, which will destroy the red blood cells of type A.
In short, A can't stand B, and B can't stand A.
The other two blood types, AB and O, belong to a different diplomatic strategy.
Type AB belongs to the take all blood group, with both A and B flags on its head. There is no guard at home. All the guests come here. No one will resist.
The O type belongs to anyone who can't stand it. No flag is inserted. The home guard team is also very powerful. The A resistance will produce the A resistance, and the B resistance will produce the B resistance. No matter who it is, it should be cleaned up.
When A antigen encounters anti A, or when B antigen encounters anti B, it will lead to the destruction and elimination of red blood cells. This process is called ABO hemolysis.
2、 Will ABO hemolysis occur in the baby born from the combination of a type O mother and a non type O father?
When women with type O blood combine with men with other blood types, they may be pregnant with babies that are not type O. However, during pregnancy, this condition rarely leads to ABO hemolysis.
Because the maternal blood circulation is relatively independent of the fetal blood circulation, and the placenta is the "intermediary" to complete the exchange of oxygen, nutrition, metabolic waste and other substances. The "middleman" isolates the blood, so that the blood will not contact directly, and the antigen and antibody will not meet each other, so hemolysis will not occur.
In addition to being like a "middleman", the placenta also acts like a screen, allowing only substances with small molecular weights to enter and exit. However, the naturally existing anti-A and anti-B antibodies in the mother's body have no chance to enter the baby's blood circulation through the placenta due to their high molecular weight (usually IgM, the largest antibody in the human circulatory system).
But when it comes to production, things will become different.
Due to hemorrhage, placental separation and other conditions during delivery, the blood between mother and baby may exchange, which creates an opportunity for antigen antibody encounter, leading to the baby's hemolysis after delivery.
In addition, a small amount of infant blood will enter the mother, which will further stimulate the mother to produce anti A and anti B (this time including IgG, a class of immunoglobulins with the smallest molecular weight), resulting in more likely neonatal hemolysis when the mother gives birth to the second child.
However, the incidence of ABO hemolysis is not as high as expected. In all pregnancies, the incidence of ABO blood group incompatibility between mother and infant is about 15%. Of these 15%, only 4% will have hemolytic disease of newborn.
Secondly, even if hemolysis occurs, the condition is often mild. Babies may show anemia and mild jaundice after birth, and the treatment is similar to that of other newborns with jaundice. In most cases, light therapy (commonly known as "blue light") is enough, and less than 0.1% of them need to use "blood exchange therapy". By the way, there is no high-quality evidence that oral administration of certain "anti jaundice drugs" or health products is effective in the treatment of neonatal hemolytic jaundice.
In a word, the combination of women with type O blood and men with other blood types may lead to hemolysis in babies, which is more common in newborns than in fetuses. The condition is often mild and easy to treat.
3、 Can ABO hemolysis be prevented?
First of all, there is no high-quality research showing that drugs can prevent neonatal ABO hemolysis. That is to say, there is no good way to find out, which may only increase worries.
Secondly, as mentioned above, even if neonatal ABO hemolysis occurs, there will rarely be serious consequences, so the "cost performance" of early prevention is not high.
Finally, compared with ABO hemolysis, it is actually recommended that pregnant mothers pay more attention to another blood type system: Rh blood type. No matter what the blood type is, as long as the mother's Rh blood type is negative, once pregnant with a Rh positive baby, fetal or neonatal hemolysis is often much more serious. If the mother is Rh negative type O blood, it needs to be protected again.
Other mothers with type O blood should rest assured that they will be pregnant. It is enough to do a regular prenatal examination during pregnancy.
Editor of this article: yutonggliu
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