Noise is a hazard for newborn. In 1997, the American Academy of Pediatrics determined that safe sound levels in the neonatal intensive care unit (NICU) should not exceed 45 dB which has been rarely achieved. High intensities of noise have several negative effects on preterm newborns. Also, they are exposed to either continuous bright light continuous near darkness or unstructured combination of the two during their hospitalizations. The investigators primary objective is to determine the impact of reduced noise levels and cycled light on growth parameters and visual development in preterm infants.