[Irregular blood group antibodies during pregnancy: screening is mandatory]

During pregnancy irregular blood group antibodies, originating either from earlier pregnancies or from blood transfusions, may severely jeopardize both mother and child. Three patients are described with pregnancy-associated blood group incompatibility. In one case of Kell antagonism a previous child had reportedly died of cot death, but in retrospect it had most probably suffered from erythroblastosis fetalis as a result of anti Kell antibodies. In the second case, a twin pregnancy, the diagnosis of neonatal haemolytic anaemia on the basis of blood group incompatibility with a very rare antibody (anti-Kpb) had been established in the previous child. No precautions had been taken during this pregnancy, putting both mother and children at risk. All three children recovered, the twins after repeated transfusion of Kpb-free erythrocytes. The described cases emphasize the importance of being informed about the presence of antibodies during pregnancy. Such information can only be obtained by assessing the antibody status during pregnancy. In the Netherlands, the screening of all pregnant women for the presence of irregular antibodies was introduced last year.