[Prenatal diagnosis and prevention of hemolytic disease of newborn].

Prenatal diagnosis and management of the hemolytic disease of the newborn are based on previous history, measurement of maternal antibody potency, amniotic fluid analysis, and fetal blood sampling. However, amniocentesis and cordocentesis are invasive procedures and bear the substantial risk of an increase in maternal antibody titer with subsequently more severely affected babies. Therefore, we determined the functional activity of the maternal antibodies by a modified monocyte-monolayer assay in comparison to the hemagglutination titer of sensitized red blood cells using selected sera with rheumatoid factor as human anti-IgG (RF titer). IgG antibodies (e.g., anti-A, -B), which can react with extraerythrocytic antigens, do not cause fetal death. Massive fetomaternal hemorrhage can induce hydrops fetalis and--in case of 0/A or 0/B blood group constellation between mother and child--may suggest a misleading diagnosis of AB0 hemolytic disease. Efficacy and costs of the pre- and postpartal Rh prophylaxis in Germany are calculated.