Objective:To evaluate characteristics of unimpaired outcome in extremely low-birth-weight (ELBW) survivors.Study design:ELBW infants (n=714) with 30 months' assessments were analyzed. Logistic regression was used to develop a model for the binary outcome of unimpaired versus impaired outcome.Result: Thirty-three percent of infants had an unimpaired outcome. Seventeen percent of ELBW survivors had a Bayley II Mental Developmental Index score of ≥101 and 2% had a score of ≥116. Female gender, use of antenatal steroids (ANS), maternal education ≥high school and the absence of major neonatal morbidities were independent predictors of unimpaired outcome. The likelihood of an unimpaired outcome in the presence of major neonatal morbidities was higher in infants exposed to ANS.Conclusion:The majority of unimpaired ELBW survivors had cognitive scores shifted toward the lower end of the normal distribution. Exposure to ANS was associated with higher likelihood of an unimpaired outcome in infants with major neonatal morbidities. © 2013 Nature America, Inc. All rights reserved.