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 .
[Effect of extensively hydrolyzed formula on growth and development of infants with very/extremely low birth weight].
OBJECTIVE To study the effect of extensively hydrolyzed formula on the growth and development in  very low birth weight ( VLBW ) and extremely low birth weight ( ELBW ) infants . METHODS A total of 375 VLBW or ELBW infants were enrolled and divided into an observation group ( 187 infants ) and a control group ( 188 infants ) using a r and om number table . The infants in the observation group were given extensively hydrolyzed formula , and when the amount of extensively hydrolyzed formula reached 10 mL/time , it was changed to the st and ard formula for preterm infants . The infants in the control group were given st and ard formula for preterm infants . Both groups were fed for 4 consecutive weeks and were compared in terms of incidence rate of feeding intolerance , time to establish full enteral feeding , time to complete meconium excretion , number of spontaneous bowel movements , growth and development , motilin level at 4 and 10 days after feeding , and incidence rate of infection . RESULTS Compared with the control group , the observation group had a lower rate of feeding intolerance ( P<0.05 ) , a shorter duration to full enteral feeding and time to complete meconium excretion ( P<0.05 ) , a higher mean number of daily spontaneous bowel movements ( P<0.05 ) , higher body weight ( 1 793±317 g vs 1 621±138 g ; P<0.05 ) , head circumference ( 30.5±1.1 cm vs 30.0±1.6 cm ; P<0.05 ) , and body length ( 43.9±1.2 cm vs 42.1±2.0 cm ; P<0.05 ) , a higher motilin level at 4 and 10 days after feeding ( P<0.05 ) , and a significantly lower infection rate ( P<0.05 ) . CONCLUSIONS Extensively hydrolyzed formula can increase motilin level , improve gastrointestinal feeding tolerance , promote early growth and development , and reduce the incidence of infection  in VLBW and ELBW 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 .