A 13-year-old female Jehovah's Witness with thromboasthenia was scheduled for scoliosis surgery. To reduce the risk of heterologous transfusion, she was given erythropoietin for 2 weeks preoperatively. Bleeding time and platelet dysfunction normalized during erythropoietin treatment, but the hemoglobin concentration increased only marginally. Desmopressin and tranexamic acid were given as cover for surgery. Blood loss was less than that in the average scoliosis patient, 1,490 ml as compared to 2,740 ml, and no heterologous transfusion was given. Erythropoietin may thus be given preoperatively, not only to increase the hemoglobin concentration, but also to improve the platelet function in thromboasthenic pa tients.