International Journal of Clinical Research

Objective To investigate the correlation between serological test results and maternal immunoglobulin G (IgG) antibody titers in neonates with hemolytic disease of the newborn (HDN) caused by maternal-fetal ABO blood group incompatibility. Methods A total of 100 neonates diagnosed with ABO-incompatible HDN in our hospital from May 2022 to December 2025 were enrolled as the study group, and 100 neonates with ABO incompatibility but without HDN in the same period were enrolled as the control group. The serological test results of both groups were retrospectively analyzed, and the IgG antibody titers of the corresponding mothers were measured to assess the correlation between serological test results and maternal IgG antibody titers. Results The positive rates of direct antiglobulin test, free antibody test, and antibody elution test were significantly higher in the study group than in the control group (P<0.05). The proportions of mothers with IgG antibody titers ≥1:64 and ≥1:256 were also higher in the study group (P<0.05). Correlation analysis revealed a positive correlation between maternal IgG antibody titers and the positive rates of the three neonatal serological tests (P<0.05). Conclusion The serological test positive rates in neonates with ABO-incompatible HDN are significantly higher, and the higher the maternal IgG antibody titers, the greater the risk of neonatal serological test positivity. There is a close association between the two factors, and combined testing can improve the accuracy of early diagnosis of HDN.

Maternal-infant ABO blood group incompatibility; Neonatal hemolytic disease; Serological testing; Immunoglobulin G antibody titer; Correlation