 Infants were recruited for gestational age—age since conception—≤27 weeks and 28 to 30 weeks and then randomized into the two groups, each totaling 500 U/kg a week.Brown and Keith found that after two weeks of r-EPO administration, Hb counts had increased and leveled off; the infants who received r-EPO five times a week had significantly higher Hb counts.This was present at four weeks for all infants ≤30 weeks gestation and at 8 weeks for infants ≤27 weeks gestation.