GUIDELINES created 20 years ago have been successful in pinpointing which girls with cancer are most likely to become infertile after treatment, according to researchers.

The criteria were set out two decades ago by Edinburgh University scientists, who tried to devise a way to select the youngsters who should be given the chance to freeze tissue from their ovaries to allow them to try to have children later in life.

New research involving 400 women who were under 18 when they were diagnosed has found the guidelines accurately predicted all but one of the patients who experienced early menopause, brought on by their cancer treatment.

Professor Hamish Wallace, of Edinburgh University's Department of Child Life and Health, said: "Advances in lifesaving treatments mean that more and more young people with cancer are surviving the disease. Here we have an opportunity to help young women to have families of their own when they grow up, if they so choose."

Professor Wallace is also consultant paediatric oncologist at the Royal Hospital for Sick Children, the only UK centre to offer selected young cancer patients the opportunity to freeze their ovarian tissue before starting their treatment. The research was carried out at the hospital in the capital.

The guidelines take into account the girls' age, type of cancer treatment and their chances of being cured.

At least 30 babies have been born from frozen ovarian tissue taken from adult women but experts say the procedure remains unproven in girls and young women.

The study, funded by the Medical Research Council, has been published in the journal Lancet Oncology.