Does human milk reduce infection rates in preterm infants? A systematic review.

One of the reasons for advocating human milk (HM) feeding for preterm infants is the belief that this provides the infant with a degree of protection from infection. Providing fresh HM for such infants is challenging for mothers and staff, and consequently it is important that its benefits are rigorously evaluated. Therefore a systematic review was undertaken to assess all publications concerned with human milk feeding and infection in very low birth weight (VLBW) preterm infants. Nine studies--six cohort and three randomised controlled trials (RCT)--were assessed using predefined criteria. Methodological problems included poor study design, inadequate sample size, failure to adjust for confounding variables, and inadequate definitions of HM feeding and outcome measures. In conclusion, the advantage of HM in preventing infection in preterm, (VLBW) infants is not proven by the existing studies. Recommendations are made regarding the methodology required for further study of this important topic.