Children born preterm are at heightened risk of lower academic achievement in math, reading, and other skills, and are also at greater risk for attention-deficit/hyperactivity disorder. But a new study suggests that an intervention in the first weeks and months of a preterm baby’s life may buffer these effects.

In research that followed preterm infants for seven years, investigators from Brigham and Women’s Hospital together with collaborators at the South Australian Health and Medical Research Institute found that children who received greater quantities of maternal milk both during and after time in the neonatal intensive care unit had greater academic achievement, higher IQs, and reduced ADHD symptoms. The results were published this month in JAMA Network Open.

“Our study finds that there may be long-term neurodevelopmental benefits to providing maternal milk to preterm infants,” said Mandy Brown Belfort, a corresponding author on the paper and an associate professor of pediatrics at Harvard Medical School. “A lot of families are dedicated to the idea of providing maternal milk, but may face steep challenges. Our findings emphasize the importance of providing support for initiating and sustaining lactation because maternal milk at this early age can provide benefits years later.”

Belfort and colleagues looked at neurodevelopmental outcomes for 586 infants born at less than 33 weeks’ gestation at one of five Australian perinatal centers. When the children were evaluated at age 7, the researchers found that higher maternal milk intake was associated with higher IQ and higher reading and math scores. Parents also reported fewer ADHD symptoms for children who consumed more maternal milk during infancy. Duration of maternal milk intake, up to 18 months, was also associated with higher reading, spelling, and math scores. The researchers controlled for confounders, including clinical and social factors. Beneficial associations were stronger for infants born at the lowest gestational ages, particularly those born at less than 30 weeks of gestation.

The authors note that the research is observational — there may be other, unaccounted factors that influence both the ability to provide maternal milk and academic achievement. The strengths of the study, they said, include its large size, the range of outcomes examined, and that the researchers could assess school-age outcomes. Other studies have only followed children through preschool age, making it difficult to assess the full range of neurodevelopmental outcomes.

Overall, Belfort sees the team’s findings as an affirmation of guidance from the American Academy of Pediatrics and World Health Organization, both of which recommend maternal milk for infants.

Our study confirms recommended strategies for supporting parents to provide maternal milk for preterm infants,” said Belfort. “And it strengthens the call for health policies and parental leave policies that support rather than work against parents. As a society, we need to invest in families — it’s an investment that will continue to benefit children when they reach school age.”