Mother’s milk boosts brain development of premature babies in intensive care

Professor James Boardman with Dr Gemma Sullivan at the Jennifer Brown Research Laboratory in 2022 (Theirworld/Phil Wilkinson).

A study of babies from the Theirworld Edinburgh Birth Cohort showed the benefits of breast milk for the part of the brain used for learning and thinking.


The Theirworld Edinburgh Birth Cohort – a world-first study of premature babies from birth to adulthood – has produced another significant piece of research. 

It suggests the more breast milk that premature babies are fed while in neonatal intensive care, the greater the level of their brain development. 

The cerebral cortex – the part of the brain for learning and thinking – is usually underdeveloped in premature babies. But in infants who consumed high levels of breast milk during the study, it quickly resembled those of babies born full term. 

Researchers from the University of Edinburgh in Scotland scanned the brains of 212 babies who are part of the Theirworld Edinburgh Birth Cohort. The group included 135 babies born before 32 weeks and 77 born at term. 

The cohort is a 25-year study of 400 babies by researchers from the Edinburgh-based Jennifer Brown Research Laboratory. It was created to improve understanding of what causes early labour, how we can develop treatments to prevent it and how we can better help newborn babies in those crucial first hours and days after birth. 

15 million

Children each year are born preterm (before 37 weeks)

Theirworld Chair Sarah Brown said: “The research and discoveries from the Theirworld Edinburgh Birth Cohort are truly remarkable. This world-first study is equipping scientists and doctors with valuable information that is expanding the frontiers of medical science and improving the life chances of premature babies. 

“I will forever be grateful to the families participating in the study who are dedicated to sharing information about their own babies, helping to give other premature babies the best start in life.” 

Premature birth is still the biggest cause of death and disability among newborn babies. Children born early are more likely to develop problems that affect their entire lives – including learning difficulties, problems with their sight and hearing, behavioural issues and cerebral palsy. 

For the breast milk study, researchers collected information about how premature babies were fed during neonatal intensive care. Brain scans were also taken of all babies at around 40 weeks from conception.  

The scans revealed that babies who received higher amounts of breast milk had a more mature cerebral cortex compared with those who received less, similar to the scans of babies born to term. 

"Healthy development of the cerebral cortex is essential for the establishment of neural networks.”

From the breast milk study.

Breast milk contains many elements – such as a favourable balance of fats, proteins and minerals, and a range of other beneficial factors that help babies’ immunity – that could support brain development, experts say.  

Dr Gemma Sullivan, Senior Clinical Lecturer in Neonatal Neuroscience at the University of Edinburgh’s MRC Centre for Reproductive Health, said: “Mothers of preterm babies should be supported to express breast milk, if they are able to, whilst their baby is in the neonatal unit as this may offer the best chance of healthy brain development.” 

Further research is needed to understand its exact role in allowing premature babies’ brains to catch up with the development seen in term babies.  

The findings have been published in the Annals of Neurology. The work was funded by Theirworld and took place at the Jennifer Brown Research Laboratory in the Medical Research Council Centre for Reproductive Health at the University of Edinburgh and the Birth Centre at the Royal Infirmary Edinburgh.