Serological conflict is a special situation in which there is a mismatch between the blood group of the mother and the child – especially in the Rh system. This triggers an immune reaction in the mother’s body that produces antibodies (anti-D) against the baby’s blood cells.
Blood group is determined by proteins (antigens) present on the surface of blood cells – especially red blood cells. They are grouped into different systems, which is why people have several groups. According to the most well-known division, these are groups: A, B, AB and 0. However, the Rh system is also very important. It consists of five antigens: D, C, c, E, e. If the first one is located on the surface of erythrocytes, the group is called Rh+. For others, it is Rh-.
When does conflict occur
Serological conflict occurs when (all these conditions will be met):
– a pregnant woman has an Rh- blood type and her partner has Rh+,
– the child inherits the red blood cell antigen pattern from the father,
– part of the child’s blood enters the woman’s bloodstream during pregnancy.
In most cases, a serological conflict in the first pregnancy can be observed only at the time of delivery.
Then the baby’s blood will most likely enter the woman’s bloodstream.
This is because during intrauterine life, the placental barrier separates the circulation of the mother and fetus.
Therefore, the body of a pregnant woman cannot produce anti-D antibodies beforehand.
It should be noted, however, that in the first pregnancy a serological conflict is possible (e.g. in the case of placental bleeding).
Anti-D antibodies remain in a woman’s body forever.
Therefore, serological conflicts may appear in subsequent pregnancies even before delivery.
This is a real threat to the child’s life.
When will there be no serological conflict
Serological conflict does not arise if:
– the woman has the Rh+ group and her partner Rh-,
– the child does not inherit the Rh group from the father,
– the woman and her partner have the Rh- group.
Serological difference
Serological difference is possible in case of incompatibility in other blood systems. We are talking here mainly about the situation when the pregnant woman has group 0, and her child inherits group A or B antigens from the father, but this is a rare situation.