ObjectiveTo investigate the effect of perioperative intravenous immunoglobulin (IVIG) on the reduction of blood group antibody titer and prognosis in children with ABO incompatible (ABO-I) liver transplantation.MethodsA retrospective study was conducted in 20 children undergoing ABO-I liver transplantation in Beijing Friendship Hospital Affiliated to Capital Medical University from July 2017 to March 2020. The changes of blood group antibody titer, alanine aminotransferase, and total bilirubin before and after operation, as well as survival rate were analyzed after intravenous IVIG during perioperative period.ResultsAfter ABO-I liver transplantation, the 1-year survival rate of 20 patients was 100%, and 1 case (5%) developed immune rejection. Compared with before operation, on the day of operation, IgM blood group antibody titer did not change in 4 cases (20%), increased in 1 case (5%), and decreased in 15 cases (75%); in one week after operation: 12 cases (60%) decreased, 5 cases (25%) increased, and 3 cases (15%) remained unchanged; in one month after operation: 18 cases (90%) decreased , 2 cases (10%) remained unchanged. Compared with before operation, the titer of IgG blood group antibody increased in 2 cases (10%), remained unchanged in 6 cases (30%), and decreased in 12 cases (60%); in one week after operation: 4 cases (20%) increased, 4 cases (20%) remained unchanged, and 12 cases (60%) decreased; in one month after operation: 3 cases (15%) increased, 4 cases (20%) remained unchanged, and 13 cases (65%) decreased. The levels of alanine aminotransferase and total bilirubin in 1 month after operation were lower than those on the day of operation.ConclusionThe effect of IVIG on reducing blood group antibody titer in children after ABO-I liver transplantation is not obvious, and its actual clinical effect needs to befurther confirmed.