Summary: Link Between Oral Contraceptives and Cervical Cancer

Women reporting the use of hormonal contraceptives for 5-9 years have been found to have 2.8 times the risk of developing cervical cancer than women who had never used hormonal contraceptives.

• In an article written in the Lancet, scientists associated with the International Agency for Research on Cancer (IARC) reported their analysis of the role of childbearing and oral contraceptives on human papillomavirus (HPV) and cervical cancer. These reports included the collection of data from case-control studies of invasive cervical cancer (eight studies) or carcinoma (two studies) taken from four different continents. The main analyses were restricted to women with cervical cancer. The researchers found that the usage of hormonal contraception for less than five years did not appear to increase the risk for cervical cancer, but women reporting the use of hormonal contraceptives for 5-9 years were reportedly found to have 2.8 times the risk of women who had never used them. The relative risk estimate was even higher (4.0) for women who had used such contraceptives for 10 years or longer. In addition, the results reported by the IARC have shown to be consistent with previous studies that have suggested that high numbers of childbearing and long-term hormonal contraception are risk factors for developing cervical cancer. Although many case-control and cohort studies not restricted to women with HPV infection have shown an association between long-term oral contraception and the risk of cervical cancer, the relative-risk estimates have generally been lower than what was shown in the IARC analysis.¹

¹Oral Contraceptives, Parity, and Cervical Cancer, The Lancet, Vol. 359, March 30, 2002, pp. 1080-1081.