Many teenage mothers carry on with unwanted pregnancies because of local antipathy to abortion, according to research for the Joseph Rowntree Foundation.

The findings are based on a survey in Doncaster, one of the 50 most deprived local authority areas in Britain, where teenage pregnancy rates are among the highest in the country.

Researchers from York university found that a young woman's decision to carry on with an unwanted pregnancy is influenced by attitudes in her community, and by high levels of teenage pregnancy and hence visible young mothers.

The study found that most teenagers were shocked when they discovered they were pregnant. Although they considered their own views held prior to the pregnancy, they were influenced primarily by the predominantly anti-abortion attitudes and experiences of those around them.

Researchers carried out in-depth interviews with 41 teenagers who had been pregnant and held focus groups with young people and parents.

The young women had few sources of impartial advice and by the time pregnancy was confirmed, had seven to 14 weeks to decide on an abortion. For those who had chosen an abortion, knowing someone who had made the same decision, or was willing to offer advice, had been an important influence.

None had become pregnant in the hope of gaining a council house or financial independence. Families played a crucial part in ensuring that young mothers and their babies became an accepted part of the extended family.

"Our research suggests that information about abortion and early motherhood should be made more available so that young women are better informed," said Sharon Tabberer, University of York research fellow and co-author of the report.

"It also identifies a need for independent counselling, advice and support for teenagers from the time they first suspect that they are pregnant. We welcome the steps that the government's teenage pregnancy unit and the pilot Sure Start Plus programme are taking along these lines."