Previous studies have demonstrated that autologous blood donors have a suboptimal endogenous erythropoietin response to the mild anemia induced by blood donation. Recent studies in baboons subjected to aggressive phlebotomy have shown an acceleration of erythropoiesis that may be beneficial perioperatively. To address the issue of accelerated erythropoiesis in autologous blood donors, red cell production during an aggressive preoperative autologous blood donation program was analyzed. The volume of red cells increased 568 mL (27% over baseline) and 911 mL (47% over baseline) for 23 placebo and 21 erythropoietin-treated patients, respectively, by hospital admission (9 days after last drug administration and 26 days after beginning therapy). The mean rate of additional red cell production was 22 mL per day in the placebo group and 34 mL per day in the erythropoietin group (p less than 0.001), which represents a twofold and a 2.5-fold increase over basal erythropoiesis, respectively. The major difference in red cell production in the placebo and erythropoietin groups occurred early in the collection period. It can be concluded that an aggressive autologous blood phlebotomy program results in clinically important increased erythropoiesis at the time of surgery. In patients unsuited for aggressive autologous phlebotomy, a more modest autologous blood procurement program, coupled with the administration of recombinant erythropoietin, may be a preferable approach.