Key findings outlined in The Journal of Pediatrics, found that babies born prematurely, who were fed breast milk within the first 28 days of life, had larger volumes of certain regions of the brain at term equivalent age.
Further assessment of these babies at 7 years of age demonstrated higher IQ, academic achievement, working memory, and motor scores.
Scientists have established that nutritional needs and brain development differ in premature babies compared to those born at full term.
Breast milk is thought of as the best food for full term infants, but those born prematurely require fortification to match third trimester nutrient accretion rates.
However, despite fortification, breast-fed infants do not gain as much weight when compared to infants fed preterm formula, raising the possibility of undernutrition.
From birth to seven
Researchers from the Brigham and Women's Hospital in the US enrolled subjects from the Victorian Infant Brain Studies longitudinal cohort. Here, 224 infants born at less than 30 weeks' gestation or weighed less than 1250 gm at birth weight were selected.
The team recorded the daily volume of breast milk and formula intake for the first 28 days of life, calculating how many days the infants received breast milk as more than 50% of their nutritional intake during this period.
Breast milk was fortified and preterm formula was used when a mother's own breast milk was unavailable or in short supply.
The team also looked at data linked to brain composition, detailed via magnetic resonance imaging (MRI). This focused on cognitive (IQ, reading, mathematics, attention, working memory, language, visual perception) and motor abilities. This was carried out at each baby's term equivalent age and at seven years old.
"Our data support current recommendations for using mother's milk to feed preterm babies during their neonatal intensive care unit (NICU) hospitalisation,” said Dr Mandy Brown Belfort, lead author and a researcher and physician in the Department of Newborn Medicine at Brigham and Women's Hospital.
“This is not only important for moms, but also for hospitals, employers, and friends and family members, so that they can provide the support that's needed during this time when mothers are under stress and working so hard to produce milk for their babies."
Mounting evidence
Research into this area has been varied with much support established for the beneficial effects of breast milk intake on neurodevelopment in preterm infants.
Studies that have looked into examined infant or toddler outcomes are encouraging but have limitations in the prediction of later cognitive abilities.
Evaluation at school age as detailed in this study also allows the study of cognitive functioning, memory, attention and school achievement.
These areas are especially crucial to evaluate in very premature infants, who have shown difficulties in these areas.
"Many mothers of preterm babies have difficulty providing breast milk for their babies, and we need to work hard to ensure that these mothers have the best possible support systems in place to maximise their ability to meet their own feeding goals,” added Belfort.
“It's also important to note that there are so many factors that influence a baby's development, with breast milk being just one."
The study was unique in that assessment of the same children at two and seven years of age was carried out.
However the team acknowledged that assessment at this early age may be too soon to detect subtle effects of breast milk that are more evident at a later school age.
“It is also possible that the influence of the shared determinants of breastfeeding and neurodevelopment, such as environmental, social, and economic factors, increases over time,” the study suggested.
Source: The Journal of Pediatrics
Published online ahead of print, doi:10.1016/j.jpeds.2016.06.045
“Breast Milk Feeding, Brain Development, and Neurocognitive Outcomes: A 7-Year Longitudinal Study in Infants Born at Less Than 30 Weeks' Gestation.”
Authors: Mandy Brown Belfort et al.