Which test would best evaluate blood type incompatibility between the mother and the fetus?

The Coombs test is the most appropriate test for evaluating blood type incompatibility between the mother and the fetus. Specifically, the indirect Coombs test (also known as the indirect antiglobulin test) is utilized to check for the presence of antibodies in the mother's blood that could affect the fetus. When a mother has a different blood type than her fetus, such as Rh incompatibility (where the mother is Rh-negative and the fetus is Rh-positive), the mother’s immune system may produce antibodies against the fetal red blood cells. These antibodies can cross the placenta and lead to conditions like hemolytic disease of the newborn.

The Direct Coombs test, on the other hand, is used to detect antibodies that are already attached to red blood cells in the infant but is not the primary test for assessing maternal-fetal incompatibility prior to birth.

The other tests mentioned do not directly address blood type incompatibility. The serum protein and albumin/globulin ratio would provide insights into different health aspects but is not specific to blood type incompatibility. Hemoglobin electrophoresis helps in identifying different types of hemoglobin and diagnosing conditions like sickle cell disease or thalassemia, but it does not evaluate immune responses related to blood type. The Dubowitz