The rate of premature births in the United States is on the rise, with one in eight babies born before 37 weeks gestation in 2003, a 13 percent increase from 10 years ago.
While it's long been known that premature birth increases a child's risk of learning and other cognitive disabilities, including lower IQ, language delay, poorer school achievement and learning disabilities, it has not been known if those problems are linked to cognitive development in early infancy.
Now a study from researchers at the Albert Einstein College of Medicine in the Bronx, N.Y., and the University of Ghent in Belgium, finds that early cognitive deficits in infancy such as poorer attention, slower processing speed and poorer recognition memory are important harbingers of later cognitive deficits, fully accounting for lower cognitive scores of 2- and 3-year-olds. The study was published in the November/December issue of the journal Child Development.
The researchers set out to address two questions: The origin of cognitive deficits in children born prematurely, and whether those deficits progressed from more elemental specific infant abilities (attention and speed of information processing) to more advanced ones (visual recognition memory and visual recognition of objects previously felt) which, in turn, influenced the general cognitive ability of these children as toddlers. The researchers examined 200 children. One group was born prematurely, with birthweights of less than 3.9 pounds (1,750 grams), the other was full term. Researchers tested the children at 7 months and at 2 and 3 years.