Other secondary outcomes will be assessed with duration of NICU admission including death and /or bronchopulmonary dysplasia in preterm infant at time of hospital discharge, necrotizing enterocolitis (NEC), sepsis with positive blood cultures, length of hospital stay, retinopathy of prematurity (ROP), time to full enteral feeding, duration of respiratory support, liver function, cholestasis defined as an elevated serum conjugated bilirubin >2 mg/dL, and metabolic response.