Birth-control pills and cancer

In women infected with the Human Papillomavirus (HPV) the risk of cancer of the cervix of the uterus (cervical cancer) increases up to fourfold with longterm use of birth-control pills (oral contraceptives). HPV is a common sexually transmitted disease (STD) that often disappears spontaneously. However certain HPV strains are linked to an increased risk of cervical cancer. Researchers at the World Health Organization's International Agency for Research on Cancer collected data from 10 studies involving patients with cervical cancer and healthy "control" patients. The analysis of eight case-control studies included 1,676 women with cancer and 255 controls, all of whom were infected with HPV. The results took into account various factors such as education, indicators of sexual activity, screening history as well as age and geographic location. The investigators found no increased risk of cervical cancer in women who had used oral contraceptives for less than 5 years as compared with women who had never taken oral contraceptives. But women who had taken the pill for 5 to 9 years were nearly three times more prone to develop cervical cancer while those who used it for 10 years or longer had a more than fourfold increased cancer risk. It was concluded that long-term use of oral contraceptives could be a cofactor in increasing the risk of cervical cancer by up to fourfold in women who are positive for cervical HPV DNA. This new research is an indicator to the different risks involved in cervical cancer. It has been known for some time that women who take the pill have a greater risk of developing cervical cancer. These results could help women who have persistent HPV infection to balance benefits such as prevention of pregnancy and ovarian cancer and the dangers of long-term oral contraceptive use. However the decision against using oral contraceptives must be a fully informed one. Cervical cancer is a risk but not a very major one. The benefits of the pill in terms of quality of life and prevention of unwanted pregnancies usually outweigh that risk.

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