People who are born prematurely may be more likely to earn lower wages as adults, a new study suggests.

According to the findings, being born prematurely appears to be linked with decreased intelligence, particularly when it comes to maths, and this may affect a person's earnings later on.

UK researchers analysed data from two large studies, one which followed children born in 1958 and one which followed children born in 1970. The data involved over 15,000 people living in England, Scotland and Wales.

All of those who were born prematurely, i.e. before 37 weeks gestation, were compared to those born full-term.

The researchers found that those who were born prematurely tended to have lower levels of intelligence, especially when it came to reading and maths. Furthermore, in both studies, maths abilities in childhood had a direct effect on how much that person earned as an adult. This was independent of their educational qualifications.

In the 1970 group, 32% of those born prematurely were manual workers compared to 25% of those born full-term, 3.3% were unemployed compared to 2.5%, and almost 58% had a family income that was below average, compared to 49% of those born full-term.

Similar figures were found in the 1958 group.

"This study is of importance because it could be used to flag up the need for extra support at school for children who are born pre-term. Numerical ability is important for making financial decisions and previous studies have linked difficulty with maths to difficulty managing personal finances and even defaulting on mortgages," commented head researcher, Prof Dieter Wolke, of the University of Warwick.

He pointed out that basic maths skills are ‘increasingly important in modern jobs'.

"Being able to identify cognitive problems early on could result in specialist, tailored education being developed to help prevent these children underachieving at school and later on as adults," Prof Wolke added.

Globally, around 15 million births every year are premature.

Details of these findings are published in the journal, Psychological Science.