Abstract: Objective To study the relationship between the blood type antibodies IgG subsets and the risk of newborns hyperbilirubinemia. Methods The serum of 50 cases high titer antibodies gravidaes and their newborns were carried out the serology detection（ABO 41 cases and Rh 9 cases）.The IgG subsets and serum bilirubin levels of 32(ABO 25 cases and Rh 7 cases)in total 41cases newborns who diagnosed as hemolytic disease were tested by the method of microcolum gel technology. Results 26 in 32 cases newborns had positive IgG1 or IgG3 synchronously. The concentration of IgG1 or IgG2 in 21 cases newborns was synchronously raised. There were 12 cases the IgG3 positive newborns developed hyperbilirubinemia and their bilirubin levels were significantly higher than that of only IgG1 positive neonates. However, there were 8 pregnant women with higher IgG2 or IgG4, their neonates were not discovered the symptom of hyperbilirubinemia. Conclusions There were positive relative for the blood type antibodies IgG subsets among the gravidaes and their neonates,especially IgG1 and IgG3 were important in pathogenesis of heamolytic disease of neonates caused by blood type. The IgG subsets detection was necessary for the high titer antibodies gravidaes. It might be helpful to early diagnose hyperbilirubinemia of newborns. The method could be provided a directional significance in early intervention of blood group incompatible hemolytic disease of the newborns and carried out an individual precise intervention treatment.

Key words: Gravida, Blood type antibody, Hemolytic disease of the newborn（HDN）, IgG subsets, Microcolum gel technology assay（MGTA）