An international review of 24 studies, involving more than 50,000 women, confirms findings of a link between birth-control pills and the incidence of cervical cancer. Researchers found that women who use oral contraceptives are at an increased risk of cervical cancer for up to 10 years after they stop.

Women who use oral contraception for five years or more double their risk of the disease. And while the risks of contracting cervical cancer diminishes when contraceptive use stops, it takes nearly a decade for the risks to return to the level for women who have never used the pill.

The authors of the report, who hail Oxford University in England, contend that the overall risks still remain small and should be seen in context.

"In the long term, the extra risk of cervical cancer in oral contraceptive users is more than outweighed by a reduction in risk of ovarian and endometrial cancers."

In developed countries, in a group of 1000 women there would normally be 3.8 cases of invasive cervical cancer by the time they were 50. If they used oral contraception for 10 years from the age of 20 and then stopped use, the figure would increase to 4.5 per 1000.

An editorial was published in "The Lancet" along with the study, in which Peter Sasieni from Queen Mary University of London said that the results should "reassure women that fear of cervical cancer should not be a reason to avoid use of oral contraception."