The evidence for the benefits from breast milk in the neurodevelopment of premature babies - a literature review

Introduction. The brain in preterm babies is usually not fully developed and therefore early post-term events can have long-lasting neurodevelopment and cognitive outcomes. It is known that cerebral white matter connectivity is important for later intact cognitive functioning amongst children born very preterm and that breast milk imparts neurotrophic factors. The relationship between breastfeeding and child development is a long and well-studied area, and the evidence in support of breast milk is already substantial. Here we review the recent literature on the topic to establish whether additional evidence is available to strengthen the view that breast milk is superior in maximizing neurological development in premature infants. Materials and Methods. A search was undertaken of PubMed, limited to the last 10 years and humans. No language restrictions were imposed. Results. The search yielded 45 articles, of which 12 included all three elements of breast milk, neurological/cognitive development and preterm babies; 10 were reviewed. The gestation period and birth weight (either or both were reported) ranged from 23 to 36 weeks and from 580g to < 1500g. Studies were heterogeneous in methodology. In addition to two systematic reviews and a review of the literature, other studies focused particularly on the effects of certain key components within breast milk on neurological development. They generally found evidence to support the beneficial effects of breast milk on brain, visual, and cognitive development in Preterm infants. Studies focusing on how breast milk intake affects the preterm infant brain are limited. We found only two studies published in the last 2 years in relation to brain volume in breast fed preterm infants. Both used magnetic resonance imaging (MRI) to examine the brains of breast-fed babies born prematurely. These studies found that preterm infants fed more breast milk had larger brain volumes (cortical surface) compared to those fed little/no breast milk. The timing of the nutritional intervention and the dose of the nutrient/supplement have been found to be relevant factors. However, not all studies have been conclusively positive. Conclusions. Although the profile of preterm infants is a wide one, from the limited but recent evidence, it is reasonable to conclude that breast milk contributes positively to neurological development.