Relationship between immune antibody titer and hemolytic disease of newborn in pregnant women with O blood group

Objective To investigate the relationships between the immune antibody( IgG antibody) titer and the incidence and degree of hemolysis of hemolytic disease of newborn in pregnant women with O blood group. Methods The IgG antibody titer was detected by using microcolumn gel assay in 512 pregnant women with O blood group before the delivery. Direct Coombs,free antibody and antibody elution tests,total bilirubin were detected by microcolumn gel assay and automatic biochemical analyzer. The relation between IgG antibody titer and the incidence and degree of hemolysis of hemolytic disease of newborn was analyzed. Results The total incidence rate of HDN was 15. 6% in pregnant women with O blood group containing immune antibodies. When the antibody titer was 1∶ 64,1∶ 128,1∶ 256 and 1∶ 512,the incidence rate of HDN was 14. 0%( 12 /86),22. 6%( 14 /62),34. 2%( 26 /76),43. 8%( 28 /64),respectively,the difference was significant as compared with the normal titer group( less than 1∶ 64),P 0. 05. The total serum bilirubin of infants with HDN rose not significantly,but no significant differences was found( P 0. 05). A positive correlation was existence between IgG antibody titer and the incidence of HDN,but not with the degree of hemolysis. Conclusion Detection of IgG antibody titer can be used to estimate the incidence of hemolytic disease of newborn. For the pregnant women with an abnormal titer level,the early intervention should be performed to decrease the risk of HDN.