Women with lupus have been urged to have more frequent tests for cervical cancer after research found they may have a higher risk of developing the cancer. A team of Chinese University researchers found that women with systemic lupus erythematosus - the most common type of lupus - are three times more likely to develop abnormal cervical cells that can lead to cancer. The researchers have called on women with lupus to have a pap smear test for cervical cancer every six months instead of the three-year interval recommended for healthy women. The study of 2,165 women - 85 lupus patients and 2,080 without it - found that 16.5 per cent of those with the disease had a non-cancerous abnormality, cervical intraepithelial neoplasia (CIN). That compared with 5.7 per cent among healthy people. Up to 10 per cent of people with CIN would develop cervical cancer if left untreated, warned Edmund Li Kwok-ming, professor of the university's department of medicine and therapeutics and a member of the team. The study was conducted in 2002 and 2003. Systemic lupus erythematosus is a disease in which the immune system attacks the body's own tissues. Researcher Tam Lai-shan estimated that seven in every 1,000 people in Hong Kong had the disease, and that it occurred 10 times more in women than in men.