Very premature babies have lower IQs, suffer academically, study finds

Babies born more than 12 weeks premature spend a lot of time in intensive care and their early delays have consequences in their school years, according to new research published online Monday in the journal Pediatrics.

Australian doctors found complications arising from early birth can have effects lasting into high school, a conclusion that differs from previous research.

The problems begin when extremely preterm babies are born before they are fully developed: they may require help with breathing and other medical interventions just to survive. They commonly suffer complications like bleeding in the brain that leads to early developmental delays.

Research to date has shown that these “biological events” after birth had a diminishing impact on cognitive functioning and academic performance as kids got older. Yet, according to the lead doctor on the new study, Lex Doyle, a pediatrician and professor of neonatal pediatrics in Victoria, Australia, his longitudinal study charts a new course.

“Conventional wisdom had been that these biological events that influence [development] would wane as they grew older and as the environmental influences increased, like how they’re reared and who rears them,” Doyle said.

This is not what his team found in its study of 298 premature babies. He said the complications from early medical interventions “persisted in their importance,” leading to significant cognitive and academic delays when compared to a control group of children who were not born early.

The researchers measured the children's cognitive skills at ages 2, 5, 8 and 18. “They’re disadvantaged by about 12 points compared with [the] control group and that persists throughout childhood,” Doyle said.

The children's academic skills were measured at ages 8 and 18 and also found to be delayed in critical areas, such as in reading, spelling and math computation, he said.

Researchers found the two main complications leading to these long-term effects were "major bleeding into the brain as a baby and severe breathing problems in the first weeks after birth that required treatment with anti-inflammatory drugs."

The mothers' levels of education and other “social variables” were studied, but the researchers found that early medical complications had the most impact on the child’s performance.

The study was possible because the Australian state of Victoria is very small. "Our population is just 6 million," he said, allowing his team to keep up with the babies as they progressed though childhood. 

Doyle said the information from this study "helps us when we talk to parents who are going to have a preterm baby to give them an idea of what they might expect when the [child] gets to this age, 18," he said. "We can advise parents that this is what you can expect at this age."