Blood group incompatibility effect is usually mild and may not be considered as a criteria for marriage. What makes up your blood group is determined by the genes inherited from your parents.. There are 4 main types: A, B, AB, O. Relationship between blood group and pregnancy  can be understood better with this scenario; the father gives while the mother takes i.e. the mother is the receiver.

Table 1.0

According to the above table, if the baby in the womb carries the father’s blood group then the above conclusion will be seen. Otherwise, if it is the mother’s blood group then there will be no issue at all even in those written as incompatibility. This means that the main factor here that determines if there will be incompatibility even in those that are not compatible is whose blood group the baby carries.

Note that blood from the baby can cross to the mother through the placenta during pregnancy. This sensitizes the mother’s immune system that there is a stranger in her and decide whether to attack it or not.

At this juncture, we need to talk about antibodies. Antibodies are what our body use to destroy what it feels as foreign or strange to it.

Blood group A carries B antibodies, means it destroys any blood group that carries B.

Blood group B carries A antibodies, means it destroys any blood group that carries A.

Blood group O has A and B antibodies, means it destroys any blood group that has A and B.

Blood group AB does not have any antibody. This means it can accept any blood, it will not destroy it.

Effect of blood group incompatibility

Usually the effect of blood group incompatibility is seen from the first pregnancy because the antibodies are already present in the blood. The body does not need extra time to produce it. What then are these likely effects? They can have miscarriage, though it is not that common. The effect can be seen in the baby after birth. They tend to have jaundice but this is not an issue as it can managed appropriately if taken to a health facility on time.

Take a look at Rhesus Incompatibility

There are two types: Rhesus positive (Rh+) and Rhesus negative (Rh-).

Rh+ blood does not have any antibody on it while Rh- has antibodies that destroy Rh+ blood on it. The determinant here is also the woman. A woman who is Rh+ who marries a man who is either Rh+ or Rh- will have no issue as she does not carry any antibody. A woman who is Rh- who marries Rh- man will have no issue. They carry the same rhesus.

Incompatibility may occur in Rh- woman who marries Rh+ man because she carries antibody which can see to that effect. There is also an exception to this. If the baby in her womb has the same rhesus factor with the mother, then there will be no incompatibility. Rhesus incompatibility usually start to have its effect in the second pregnancy as the body needs enough time to produce antibodies after being sensitized. They get sensitized when blood crosses from the baby to the mother through the placenta during pregnancy or delivery.

How do you prevent the effect of Rhesus Incompatibility?

The mother must take an injection called RHOGAM within 72hrs of delivery to neutralize those antibodies. Such babies can have jaundice after birth which can be managed if taken to the health facility as soon as it was noticed.