All infants were tube fed (or cup fed) until breastfeeding was established. Non-nutritive sucking was encouraged. Infants’ sleep-wake states and feeding cues were acknowledged, and infants could be fed (either at breast or by tube ) based on their signals rather than at scheduled time. During tube feeding the infant was observed and if he or she became ill or nauseous, the tube feeding on demand and did not have an optimal weight gain (increase by 15-30 grams/day),theinfant could go home on leave for 1to 2 days and then come back to the NICU for weighing and possible discharged at anygestational week.