Smallest Babies Can Make Big Gains in IQ
New research confirms low birth weight babies improve mental abilities as they age

By Ed Edelson
HealthScoutNews Reporter

TUESDAY, Feb. 11 (HealthScoutNews -- A new study offers hope for very low birth weight babies and their parents.
The study, which followed 296 children who weighed no more than 44 ounces at birth, finds that many of them show a steady improvement in verbal ability and IQ scores in their first eight years of life, says a report in the Feb. 12 Journal of the American Medical Association.

More than 50,000 babies born each year in the United States are classified as very low birth weight because they weigh no more than 3 pounds, 5 ounces at birth. Because of their neurodevelopmental disabilities, previous studies had found that up to half of them require assistance in school and 20 percent need special education. More recent studies have painted a more promising picture: Almost 75 percent of these children graduate from high school and 40 percent enter college.

The latest study was done to see whether those more hopeful reports were accurate. Study author Dr. Laura R. Ment and her colleagues at the Yale University School of Medicine followed 296 children who had been part of a brain-bleeding prevention study at three northeastern hospitals between September 1989 and August 1992.

The children had been studied intensively at birth because they had suffered both brain hemorrhages and significant brain damage. Between the time they were 3 and 8, the Yale researchers periodically gave them the Peabody Picture Vocabulary Test, which measures verbal comprehension, and the standard Wechsler IQ test.

Nearly half the children had increases of at least 10 points on the verbal comprehension test between age 3 and age 8, the researchers report, and 71 percent of those who scored in the borderline range at age 3 were in the normal range by age 8. Almost half of those with IQs in the mental retardation range -- below 70 -- at age 3 were in the normal range by age 8. Less than a quarter of the children had scores that decreased with time.

"These results are the first indication that the brain may recover from injury over time in these children," says a statement by Ment.

Asked if the results were better than anticipated, Ment, a professor of pediatrics and neurology at Yale, says, "We were thrilled, absolutely thrilled."

But it was forecast by animal studies, she adds, which show that "in response to an injury, the developing brain seems to recover. There is neurogenesis [growth of nerve cells] and a catchup in performance."

As for environmental factors, children living in a two-parent family did best, Ment says. "Maybe it's just having more time for the child," she adds.

An equally important factor, she notes, was the mother's education: more years of education was associated with more improvement.

The numbers have both personal and societal significance, the report says. "The societal implications of a five-point difference in IQ are large," it says. "Remedial education in many school districts costs close to an additional $60,000 per student. In addition, the label 'special education' carries with it significant personal stigmatization."

The report is "encouraging," says Glen P. Aylward, a professor of pediatrics and psychiatry at Southern Illinois School of Medicine who wrote an editorial that accompanies the study.

"But I think we need to exercise caution, primarily because lots of potential deficits in these babies were not measured in the study," he adds.

The researchers could not measure such things as behavioral problems and planning and organization ability, Aylward notes. However, one of the strengths of the study is that it identifies environmental factors that can influence how well a child will do, he says.

"Environment plays a major role, particularly with verbal outcome," he adds.

The study is continuing to see whether that is true, Ment says, adding "They're coming in now at age 12, and we hope to follow them until high school graduation."