It has nothing to do with your blood type or the type determined by the ABO system, but rather with something called the rhesus (Rh) factor, which determines whether your blood type is positive or negative. If the baby’s Rh blood group is different from the mother’s, it can lead to complications in the pregnant woman.
For example, if the mother’s blood type is negative and the baby’s is positive, the mother’s body may build up antibodies once morest the baby’s blood type. It does not affect the baby, but it might have a negative effect on future pregnancies.
Fortunately, doctors can give pregnant women an injection early in their pregnancy to prevent Rh incompatibility issues.
