(HealthDay)—Babies born between four and six weeks early are more likely than full-term babies to suffer a lifetime of socioeconomic disadvantages, Finnish researchers report.
However, the study results are based on babies who were born prematurely between 1934 and 1944, which could lessen the modern-day relevance of the findings, experts noted.
Pediatric experts also questioned the point of the study, given that late-preterm deliveries are nearly always medically necessary to protect the health of mother or child.
"I hope no one is undertaking late-preterm births by choice. They are not elective things," said Dr. Jeff Ecker, director of obstetrical clinical research and quality assurance for Massachusetts General Hospital.
"Any efforts to avoid late-preterm births have to be balanced against the consequences to the mother's health or the baby's health. I don't think they are as easily avoided as some might wish or imagine," added Ecker, who was not involved with the study.
One out of every 10 births across the world are premature (before 37 weeks' gestation), and more than 70 percent of all preterm deliveries are late-preterm (defined as 34 through 36 weeks), according to background information provided in the study. Babies born late-preterm have higher risk of medical and developmental disabilities and suffer more often from mental and behavioral problems.
Katri Raikkonen of the University of Helsinki and colleagues studied nearly 9,000 Finnish men and women born between 1934 and 1944. They tracked the arc of these people's lives, comparing the social and economic status into which they were born with the status they had attained by their late 50s or early 60s.
The investigators found that babies born late-preterm were more likely to be manual workers in adulthood, compared to babies born at full-term. They also were more likely to have missed out on receiving a higher education, to be downwardly mobile and belong to the lowest third of society based on their incomes.
Overall, the late-term preemies made less money, worked blue-collar jobs and had poorer educations than the full-term babies, according to the findings published in the October issue of the journal Pediatrics.
"This suggests that the 10 million people born late-preterm each year may be at risk for suffering from lifetime socioeconomic disadvantage," Raikkonen and colleagues concluded in the report.
However, experts said the finding carries one important caveat.
"While it's true that late-preterm babies born today have perceptible development differences compared with full-term babies, the people involved in this study were born during a time when there was a 40 percent mortality rate for premature deliveries," said Dr. Andrew Adesman, chief of developmental & behavioral pediatrics at Steven & Alexandra Cohen Children's Medical Center of New York in New Hyde Park, N.Y.
"You're talking about a caliber of care that is vastly different and an incidence of mortality that is just huge by western 21st century standards," Adesman said. "Here we are nearly 70 to 80 years later. The clinical relevance is questionable, and I think an article like this has the potential to unduly alarm parents who have a child born one to three weeks earlier than is expected for a full-term infant."
Dr. Ari Brown, a pediatrician based in Austin, Texas, agreed.
"Late-preterm infants today are medically managed much more aggressively, since we know so much more than we did back then," Brown said. "Just managing jaundice—very common in preterms—aggressively decreases the risk of kernicterus, a lifelong adverse effect on the brain, which could have affected some of these babies back then."
Premature babies also are more likely now to receive early childhood intervention or developmental follow-up to make sure they get help for any learning disabilities that might crop up, Brown added.
"I wish we could just prevent preterm deliveries, but we don't routinely create these situations," Brown explained. "They arise, and labor is unstoppable. We just have to know how to take care of these babies and follow them closely."
Explore further: Babies born 32-36 weeks fare less well at school
For more on preterm birth, visit the U.S. Centers for Disease Control and Prevention.