Blood Type of a Child Born to an O-Type Father and a B-Type Mother

Question

I am B-type blood, and my husband is O-type blood. What blood type will our child have?

Answer

If the mother is B-type blood and the father is O-type blood, the child’s blood type can be either B-type or O-type. It cannot be A-type or AB-type. This situation will not cause hemolytic disease of the newborn, but only if the mother is O-type blood and the father is AB-type blood, and the fetus is AB-type. Since O-type mothers have AB antibodies, and the fetus has AB antigens, if the mother’s blood contains anti-AB antibodies that enter the fetus, they can combine with the fetus’s AB antigens, which may lead to neonatal hemolytic disease. However, this probability is also very low.