Approximately 60,000 premature infants are born each year who weigh less than 1,500 grams,many of whom sustain brain damage because of their prematurity. This study is designed to evaluate the long-term developmental effects of one promising neuroprotective treatment,erythropoietin (Epo), when given in the neonatal period. Using detailed neurodevelopmental testing and state-of-the-art brain imaging, we hope to determine whether this is an effective treatment to prevent brain injury associated with prematurity, and to lay the groundwork for further studies to improve the developmental outcome of infants delivered prematurely.