For children who entered the world preterm, maternal milk early in life is tied to better school-age outcomes, a new study suggests. Photo by Praisaeng/Shutterstock
Seven-year-olds who began life as preterm infants had stronger academic performance and fewer attention-deficit/hyperactivity symptoms if they got maternal milk in early life, a study released Wednesday said.
In a study that followed preterm infants for seven years, investigators from Brigham and Women’s Hospital in Boston, found that children who received “higher maternal milk intake” during and after time spent in the hospital neonatal intensive care unit had higher performance IQ.
They also had better academic achievement in reading and math, and fewer parent-reported symptoms of attention-deficit/hyperactivity disorder at school age.
The study, conducted in conjunction with together with the South Australian Health and Medical Research Institute, was published in JAMA Network Open.
“The children were evaluated at age 7 to allow the assessment of school-related outcomes and other challenges, such as ADHD-related symptoms, that may not be evident until school age,” Mandy Brown Belfort, the study’s corresponding author and attending neonatologist at Brigham and Women’s Hospital, told UPI in an email.
“This is longer follow-up than most other studies that assessed children around 18 months or 3 years of age,” said Belfort, who also is an associate professor of pediatrics at Harvard Medical School.
Children who are born preterm are known to have a heightened risk of lower academic achievement in math, reading and other skills, and also are at greater risk for ADHD, the researchers noted.
According to the Centers for Disease Control and Prevention, preterm birth is defined as occurring before completion of 37 weeks of pregnancy.
In 2020, preterm birth affected one of every 10 infants born in the United States, the CDC reported.
The preterm birth rate declined slightly from to 10.1% in 2020 from 10.2% in 2019, but racial and ethnic differences in the rates remained. In 2020, the rate of preterm birth among African-American women was 14.4%, compared with the rates among white or Hispanic women, at 9.1% and 9.8%, respectively.
The new study’s findings affirm the World Health Organization’s recommendation for maternal milk for infants during the first six months of life, the researchers said, and also support a policy issued by American Academy of Pediatrics in November that promotes the use of a mother’s own milk for hospitalized very low birth weight infants to gain short- and long-term health benefits.
Belfort said the main practical implications of the study “relate to how we support lactation in the NICU.”
This might include hospital funding for NICU-based lactation consultants who provide education for new mothers and support them as challenges arise and funding for high quality breast pumps and other equipment,” she said.
“Paid parental leave and accommodations in the workplace are also critical because many mothers need to go back to work shortly after they deliver, in order to save their leave for when the baby comes home from the hospital,” Belfort added.
Dr. Lawrence Noble, a neonatologist who co-authored the AAP’s clinical report urging neonatal staff members to support mothers in breastfeeding their infants in the NICU, said this is not the first study that shows a mother’s milk can help improve a baby’s IQ. But, he said, it offers three “exciting” findings.
“For preterm infants, mother’s milk in a sense is almost medication, [but] we don’t have a medication that can cause the same effect” on neurodevelopment, Noble, associate professor of pediatrics at Icahn School of Medicine at Mount Sinai in New York City, told UPI.
So, the new study’s first important finding is that “any amount you give is good, but more is better,” he said.
Of maternal milk for preemies, Noble said, “A little helps, and a little more helps a little more.” He noted that the research involved mother’s own milk, not donor milk.
Noble also pointed out the research found that duration mattered. Maternal milk intake up to 18 months was associated with higher reading, spelling and math scores, they found.
“This is really exciting information,” Noble said. “If maternal milk continues after [the infant’s release from] the hospital, that also might make a difference.”
He added, “We should be telling mothers of preterm infants that the longer they can breastfeed their baby, the better the outcomes could be for their infants.”
Noble also pointed to the study’s finding that the benefits were stronger for infants born at the lowest gestational ages, particularly babies born at less than 30 weeks of gestation.
“The more premature the baby is, the greater the chance of neurodevelopmental problems,” he said, and mother’s milk may help change the equation.
Belfort, too, said it was “particularly interesting” to her “that the beneficial associations were strongest in the smallest and most immature infants — this was something that previous studies were not able to look at.”
The new study included 586 infants born at less than 33 weeks’ gestation at one of five Australian perinatal centers. Children were evaluated at age 7 (as corrected for their preterm birth).
The authors noted that their study is observational and may not have accounted for all factors.
But they cited the study’s large size, the range of outcomes examined, and their ability to assess school-age outcomes — not limiting the analysis to preschool age as some previous studies have done — as its strengths.