In the ELGAN (Extremely Low Gestational Age Newborn) study, abnormal brain structure and function were associated with intermittent or sustained systemic inflammation (ISSI). Since EPO has anti-inflammatory properties in the kidney and in muscle as well as growth/trophic properties. Based on its potential for neuroprotection, the prospective randomized and masked study was designed to determine whether rhEPO （500u/kg) was also effective in improving developmental outcomes for extremely low gestational age newborns.