The identified trials provide only low quality evidence about the effects of feeding preterm infants  with protein hydrolysate versus st and ard formula .
The existing data did not support conclusions that feeding with protein hydrolysate affects the risk of feed intolerance or necrotising enterocolitis .
BACKGROUND When human milk is not available for feeding preterm infants , protein hydrolysate rather than st and ard cow 's milk formulas ( with intact proteins ) are often used because they are perceived as being tolerated better and less likely to lead to complications .
However , protein hydrolysate formulas are more expensive than st and ard formulas , and concern exists that their use in practice is not supported by high- quality evidence .
OBJECTIVES To assess the effect of feeding preterm infants with hydrolysed formula ( versus st and ard cow 's milk formulas )  on the risk of feed intolerance , necrotising enterocolitis , and  other morbidity and mortality in preterm infants .
Extensively and partially hydrolysed infant formulas for allergy prophylaxis
The allergy preventive effect of extensively ( N ) and partially ( PH ) hydrolysed cows ’ milk formulas compared with a regular formula ( RM ) was assessed in 155 infants with a family history of allergy . No cows ’ milk was given during the first nine months of life and no egg and fish  up to 12 months of age . Breast feeding mothers avoided the same foods . At weaning the infants were r and omised to one of the formula groups . The cumulative incidence of atopic symptoms at 18 months was 51 , 64 , and 84 % in the N , PH , and RM groups , respectively . From 6 to 18 months there were significantly less cumulative atopic symptoms in the N group compared with the RM group , and significantly less than the PH group up to 6 ( N = 25 % ; PH = 46 % ) and 9 months ( N = 34 % , PH = 58 % ) . At 9 months significantly fewer infants in the N group ( 10 % ) than in the PH group ( 33 % ) had a positive skin prick test to eggs . The findings support an allergy preventive effect of an extensively hydrolysed formula , but not of a partially hydrolysed formula , during the first 18 months of life of high risk infants
The identified trials provide only low quality evidence about the effects of feeding preterm infants  with protein hydrolysate versus st and ard formula .
The existing data did not support conclusions that feeding with protein hydrolysate affects the risk of feed intolerance or necrotising enterocolitis .
BACKGROUND When human milk is not available for feeding preterm infants , protein hydrolysate rather than st and ard cow 's milk formulas ( with intact proteins ) are often used because they are perceived as being tolerated better and less likely to lead to complications .
However , protein hydrolysate formulas are more expensive than st and ard formulas , and concern exists that their use in practice is not supported by high- quality evidence .
OBJECTIVES To assess the effect of feeding preterm infants with hydrolysed formula ( versus st and ard cow 's milk formulas )  on the risk of feed intolerance , necrotising enterocolitis , and  other morbidity and mortality in preterm infants .