Abstract: Objective By comparing and analyzing the related indexes of hemolytic disease of the fetuses and newborn (HDFN) in fetuses and newborns delivered by RhD-negative pregnant women, we can provide reference and guidance for the prevention and treatment of HDFN. Method A total of 737 RhD-negative pregnant women who gave birth in our hospital from January 2018 to December 2022 were collected. The relative factors of HDFN caused by RhD blood group incompatibility and ABO blood group incompatibility, RhD-HDFN and ABO-HDFN were compared. Moreover, the differences of laboratory indexes between RhD-HDFN and ABO-HDFN and RhD-HDFN in newborns with IgG anti-D titer ≤16 and ≥32 were analyzed. Results Among 737 RhD-negative pregnant women, 88.89% (40/45) had the same or compatible ABO blood type between mother and infant, which was significantly higher than 11.11% (5/45) in mother-infant ABO blood type incompatibility. Maternal second pregnancy and above births had a 93.33% (42/45) RhD-HDFN rate which was significantly higher than the 60.66% (37/61) ABO-HDFN rate. In addition, the lowest hemoglobin value in newborns born to mothers with IgG anti-D titers ≥32 was significantly lower than that of mothers with IgG anti-D titers ≤ 16 (χ²=5.61, P<0.05). As expected, the peak value of serum total bilirubin in newborns born to mothers with IgG anti-D titers ≥32 was higher than those with IgG anti-D titers ≤ 16 (χ²=4.471, P<0.05). Conclusion Among RhD-negative pregnant women, those with the same or compatible ABO blood type and gravidity and parity history ≥2 are more likely to develop RhD-HDFN in their corresponding newborns and the severity of neonatal hemolysis is significantly higher in those with maternal IgG anti-D titer ≥ 32 than in those with anti-D titer ≤ 16.

Key words: RhD-negative pregnant women, Hemolytic disease of the fetus and newborn, Exchange transfusion therapy, Anti-RhD immune globulin