Abstract: Objective To study the Rh phenotype distribution among blood recipients, and to determine crossmatch compatibility rules of their red blood cells (RBCs). Methods Aigel 300 was used to detect and transmit ABO blood type, Rh phenotype, irregular antibody screening for 1 117 blood recipients, and Rh phenotype for 3 174 blood donors. TMIS9.5 was used to receive and crossmatch the Rh phenotypes for both the donor and the recipient. On the 15th day after transfusion, blood recipients would be followed up for 6 months, and SPSS 25.0 was used for risk assessment. Results Outcomes of donor- recipient matched RBC transfusions in Xi'an area: The probability of transfusion level Ⅲ for recipients was 17.82%, and the probability of matching level Ⅲ for donors was 8.99%. In 918 patients with grade Ⅰ+Ⅱ (matched transfusion), 8 of which had positive screening antibodies before transfusion; One out of 199 patients with grade Ⅲ had a positive screening antibody before transfusion. Six months later, 448 recipients with grade Ⅰ+Ⅱ were traced, and one new case was a positive screening antibody (non-Rh antibody); Among 91 recipients with grade Ⅲ, 4 new cases were anti-screening antibodies (all anti-Rh antibodies). The risk of RBCs transfusion with Rh phenotype grade Ⅲ was significant [χ_Ⅲ²=5.586,P_Ⅲ<0.05;OR_Ⅲ=9.103 ,95%CI_Ⅲ=（1.003,82.633）]; while, that of grade Ⅰ+Ⅱ was not significant[χ_Ⅰ+_Ⅱ²=0.191,P_Ⅰ+_Ⅱ>0.05;OR_Ⅰ+_Ⅱ=1.284,95%CI_Ⅰ+_Ⅱ=（0.418,3.947）]. Conclusion The distribution of donor-recipient Rh phenotype in Xi'an area accorded with the basic demographic characteristics. It is recommended that patients with fertility needs and normal immune function avoid blood transfusion. When transfusion is necessary, they should follow the matched Rh phenotype grade Ⅰ+Ⅱ or avoid the most risky antigens among E, c, C, e and D in sequence.

Key words: Blood recipient, Blood donor, Rh phenotype, Matched infusion