Over half of children born extremely prematurely need extra educational support in mainstream schools, reveals research published ahead of print in the Fetal and Neonatal Edition of Archives of Disease in Childhood.
In particular, they struggle with maths, the research indicates.
The research team analysed the intelligence (cognitive ability) and academic prowess of 219 eleven year old schoolchildren who had been born before 26 weeks (of pregnancy) in 1995 in the UK.
Their performance was compared with that of 153 classmates who had all been born after a normal length pregnancy.
The assessments were based on standard tests of IQ and academic achievement as well as teachers' reports of school performance and any special educational needs.
The results showed that children who had been born extremely prematurely scored significantly lower on IQ and the core subjects of reading and maths.
Boys scored significantly fewer points than the girls, except for maths. There were no such sex differences among their classmates.
One in three children born extremely prematurely found reading difficult, while almost half (44%) battled with maths. These children also found simultaneous processing of complex information especially difficult.
Only 29 of the children were at special schools. The rest attended mainstream schools, where over half (57%) had special educational needs, most of which required additional learning support.
In all, two thirds had academic and behavioural special educational needs compared with 11% of their classmates and 24% of schoolchildren across England. They were also more likely than their classmates to require multiple support services.
Teachers rated the academic performance of half of their charges who had been born extremely prematurely as below the average range expected for their age, compared with just 5% of children born after a normal length pregnancy.
Many children born extremely prematurely will end up starting school an academic year earlier, because their birth date is earlier than expected, say the authors.
Although the academic performance of these children was similar to those who had started school at the normal time, they needed even greater levels of special needs support, the research showed.
"The impact of these impairments is likely to increase over time," conclude the authors. "...existing difficulties may be exacerbated in secondary school when cognitive demands increase in parallel with progressively complex academic studies," they add.