Abortion rates among 15- to 17-year-olds vary dramatically around the country, with young women from socially disadvantaged areas far more likely than those in affluent parts to keep the baby, a study reveals today.

More than 40% of pregnancies in this age group end in termination, but the figure disguises a gulf in social class. In the Derwentside area of County Durham, less than 20% of unintended pregnancies end in abortion, compared with 75% in the Eden district of Cumbria.

The report, prepared for the Joseph Rowntree Foundation by the centre for sexual health research at Southampton University, found that the decision to abort was based on personal circumstances. Those who did not see long-term university or career prospects were more likely to become pregnant and less likely to seek abortion.

"Teenagers who saw their lives as insecure were more likely to accept motherhood as a positive change in their lives. Those who saw their lives developing through education and employment were more likely to opt for an abortion," said the report.

Ellie Lee, co-author, said: "The evidence shows that their views are shaped by factors that include social deprivation, the attitudes of family and friends and the accepted 'norms' of behaviour in the communities where they live."