The Early Baby Doesn't Always Get the Worm

Children born late preterm at higher risk for lower socioeconomic status later in life

(RxWiki News) For different reasons, preemies are known to face greater challenges than other children as they grow up. The closer to full term a child's birth is, the greater the likelihood is of good health.

In fact, a recent study found that being born even a couple weeks early may have long-term effects on a person's life.

The effects studied in this paper related to economic and social positions of people who had been born up to two weeks before full term.

The reasons for these findings are not clear, but the authors presented several possibilities.

"Attend all prenatal appointments."

A study, led by Kati Heinonen, PhD, of the Institute of Behavioral Sciences at the University of Helsinki, in Finland, looked at the lifetime effects of being born only a few weeks early.

The researchers tracked 8,993 Finnish men and women who were born between 1934 and 1944 until they were between 56 and 66 years old.

The researchers compared the week of pregnancy when they were born to how high on the socioeconomic ladder they ended up in life.

The researchers specifically compared those who were born at term (between 37 and 42 weeks of pregnancy) with those born "late preterm," between 34 and 36 weeks of pregnancy.

The results were adjusted to account for the children's parents' socioeconomic positions starting out.

By a variety of measures, the researchers found that those born between 34 and 36 weeks of pregnancy were less likely to achieve higher socioeconomic levels than those born on time.

The participants who had been born late preterm were about 1.6 times more likely to be manual workers than those born on time.

Those born late preterm were also about 1.3 times more likely to have a basic or upper secondary level of education — but not higher — than those born at full term.

The late preterm participants were also more likely to be in the lower third of society in terms of their income (1.3 times more likely), and they were about 25 percent less likely to be in the upper third, compared to those born on time.

"Late preterm individuals were also less likely to be upwardly mobile and more likely to be downwardly mobile," the researchers wrote.

"They were less likely to have higher occupations and more likely to have lower occupations than their fathers," they wrote.

The findings were similar to another set of findings in Norway regarding late preterm children after they grew up.

That study found a higher risk for medical disabilities among those born late pre-term but not any differences in highest level of education achieved. That study did not follow participants for as long as this study did.

The researchers suggested various reasons that could explain their results, though none are certain.

They noted that a significant part of a baby's brain development occurs in the last couple of weeks of pregnancy, which could mean children born earlier are more vulnerable.

They also noted that past research has shown "...those born late preterm are at an increased risk for problems in neurocognitive functioning, suffer more often from school-related problems and display more behavioral, emotional and attention problems than those born at term."

They also noted that there have been past links found between preterm birth and the mother's physical and mental health, so the mother's health may influence the child's development and future support of the child.

The researchers also noted that there may be genetic reasons for the findings, though none of these possibilities are necessarily more likely than others, and some could be incorrect.

The study was only able to find that the link exists, not necessarily explain why it exists.

"This study demonstrates that there are considerable long-term socioeconomic disadvantages associated with late preterm birth, which are not explained by the parent-of-origin socioeconomic position," the researchers wrote.

Andre Hall, MD, an OBGYN at Birth and Women's Care, PA in Fayetteville, NC, said he is not aware of other studies that look at this issue for the long-term, but there are things research has revealed already.

"We know that as a group, babies born at term have fewer medical and developmental problems than babies born preterm," he said. "The increased number of developmental problems will often cause these preterm babies to hit their benchmark milestones later than their full term counterparts."

Dr. Hall said it is possible that some of these delays are never completely erased.

"According to this study, it is possible that these early delays extend into adulthood and ultimately affect socioeconomic status in life," Dr. Hall said. "One thing we can say for certain: There are numerous reasons that premature deliveries should be avoided wherever possible, some immediate and some delayed possibly over a lifetime."

The study was published September 30 in the journal Pediatrics. The authors declared no conflicts of interest.

The research was funded by the Academy of Finland, the University of Helsinki, the Paivikki and Sakari Sohlberg Foundation, the Finnish Diabetes Research Foundation, the Finnish Foundation for Pediatric Research, the Finnish Medical Society Duodecim, Yrjo Jahnsson Foundation, Signe O. Ane Gyllenberg Foundation, the Juho Vainio Foundation and the Sigrid Juselius Foundation.

Review Date: 
September 29, 2013