A multi-center cohort study in which surviving extremely low birth-weight infants undergo neurodevelopmental, neurosensory and functional assessment at 18-22 months corrected age. Data regarding pregnancy and neonatal outcome are collected prospectively. Social and economic status information (SES) and a detailed interim medical history are obtained at the time of the assessment. The scheduled evaluations at 18 - 22 months corrected age include: demographic information; socioeconomic status; medical history; medications; medical equipment required; growth data; a detailed neurologic examination; Bayley Scales of Infant Development (mental, motor, infant behavior); Family Resource Scale; Stein Functional Status II Measure and the Stein Impact on the Family Scale.

The goal of the study is to identify maternal and neonatal risk and protective factors for neurodevelopmental outcome. Additional objectives of the study include: to characterize development in the areas of motor skills, cognitive skills, language and behavior; to determine the mortality and the prevalence of specific medical morbidities in ELBW infants; to characterize the relationship between growth and neurodevelopmental outcome; to assess the relationship between the socioeconomic status and developmental outcome; to identify significant family stress in this population and compliance with medical and developmental care; to assess the utilization of special support services and early intervention programs by this population; and finally, to evaluate the need for follow-up to school age. The Follow-Up Study has maintained its goal of greater than or equal to 80 percent follow-up compliance rate.

• < 1000 g at birth
• Patient enrolled at a Neonatal Research Network center