575 patients scheduled to receive primary THA or TKA were randomly assigned to 1 of 3 groups to determine the effect an autologous blood transfusion applied at two postoperative intervals had on blood transfusion rate. Patients had their drain removed after 6 or 24 hours, (following autologous blood reinfusion) or received no wound drainage at all. 41 patients received a transfusion by the end of the study, but the occurrence of transfusions did not differ between groups. Additionally, following treatment, no difference existed between the groups when comparing postoperative Hb values, measured peri-operative blood loss, transfusion volumes, length of hospital stay, or adverse events.