Therapy was initiated by day of life 4 and continued through the 35th postmenstrual week. Infants were randomized to receive either Epo and iron therapy or a sham procedure. Treated infants received 400 U/kg Epo 3 times weekly and a weekly intravenous infusion of 5 mg/kg iron dextran until they had an enteral intake of 60 mL/kg/d. Infants in the placebo/control group received sham subcutaneous injections when intravenous access was not available. Complete blood and reticulocyte counts were measured weekly, and ferritin concentrations were measured monthly.