Neurodevelopmental impairment: All study infants will follow up at 18-24 months of age in the high risk Low Birth Weight Clinic. A blinded developmental pediatrician will perform standardized neurological examination to identify cerebral palsy. Developmental specialist will administer the Bayley Scale of Infant Development III Instrument. Moderate to severe neurodevelopmental impairment will be defined as Bayley III Motor Developmental Index or Psychomotor Developmental Index score less than 70, moderate or severe cerebral palsy, bilateral blindness, bilateral hearing loss requiring hearing aids or cochlear implants.