Premature babies grow up to be less intelligent and have more problems at school than other children, researchers say.

A study suggests that children born early are nearly three times as likely to be low achievers or have other special needs in school.

It also indicates they are likely to be less socially successful, with fewer friends than their peers.

The research was carried out by psychologists at Syracuse University in New York.

The children were tested regularly for 10 years

Presenting their findings to the national convention of the American Psychological Association, they said the study was important because more premature babies were now being kept alive.

"The prevalence of school problems with pre-term children is staggering and warrants greater attention from school professionals," they said.

The study compares the development of 118 babies born prematurely, at 24 to 31 weeks, with 119 babies delivered after 38 to 42 weeks.

Learning disabilities

The researchers based their conclusions on tests which started at birth and continued at intervals over 10 years.

They found that 39% of the premature babies had below normal IQs of 85 or less, compared with 13% of the babies carried to full term. The international average is only 16%.

Of the premature children, 61% had special needs or were "low achievers" in school, compared with 23% of the full term children.

And 28 of the 118 premature children were classified as having learning disabilities, compared with 11 of the full term children.

Parenting skills

Professor Lewandowski, one of the co-authors of the study, said earlier studies had shown that children born prematurely were up to four times less likely to graduate from high school than other children.

He said the new research indicated that parents of premature babies needed to make a special effort to enrich the social and intellectual development of their children, and that they should seek professional help to learn special parenting skills.

"Our research suggests that interventions should be implemented for all pre-terms as early as possible to halt or prevent future problems and closely monitor their social, behavioural and academic progress."