Impaired erythropoietin response in anemic premature infants

Serum erythropoietin (ESF) levels were measured by the polycythemic mouse bioassay in a group of normal premature infants with physiologic anemia. No ESF was detected in these infants, while a group of older anemic children with similar hematocrit values had elevated levels. A impaired ESF response in these infants may be an important factor in the pathogenesis of the anemia of prematurity. Tissue oxygen requirements in the premature infant are probably met in some way despite diminished ESF production and low hematocrit levels.