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 hydrolyzed protein formula reduces acid gastro-esophageal reflux in symptomatic preterm infants.
BACKGROUND Gastro-esophageal reflux ( GER ) is diagnosed frequently in preterm infants . Pharmacological treatment of GER has some potential side effects . Conservative treatment of GER should be the first-line approach and should include body positioning and diet modifications . Formula-fed preterm infants experience frequently symptoms of feeding intolerance . Hydrolyzed protein formula ( HPF ) is often used in these infants due to their effects on gastrointestinal motility . AIMS To investigate the role of an extensively HPF ( eHPF ) on GER indexes in formula-fed preterm infants with symptoms of both GER and feeding intolerance . STUDY DESIGN R and omized crossover trial . SUBJECTS Preterm infants ( gestational age ≤33 weeks ) with symptoms of feeding intolerance ( large gastric residuals , abdominal distension and constipation ) and GER ( frequent regurgitations and /or postpr and ial desaturations ) . OUTCOME MEASURES GER indexes detected by 24-h combined multichannel intraluminal impedance and pH monitoring . GER indexes detected after 4 feeds of an eHPF were compared to those detected after 4 feeds of a st and ard preterm formula ( SPF ) by Wilcoxon signed ranks test . A p<0.05 was considered statistically significant . RESULTS eHPF significantly reduced the number of GERs detected by pH monitoring ( p=0.036 ) and also the reflux index ( p=0.044 ) compared to SPF . No differences in impedance bolus exposure indexes nor in GER height were detected . CONCLUSIONS The use of an eHPF should be evaluated for reducing esophageal acid exposure in preterm infants with feeding intolerance and symptoms of GER . Future research should focus on the evaluation of an eHPF adequate for preterm infants in improving clinical symptoms of GER
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 .