Researchers from the World Health Organization (WHO) collected data from 10 international studies concerning women with cervical cancer to find that women infected with the human papilloma virus (HPV) who had used oral contraceptives for more than five years were 2.82 times more likely to develop cervical cancer than women who had not used oral contraceptives. Women with HPV who used birth control for ten or more years were 4.03 times more likely to develop cervical cancer. The heightened risk persisted for up to 14 years after women stopped using birth control. Importantly, the study did not distinguish between oral contraceptives and other hormonal contraceptives, though researchers assume that the majority of women participating were using oral contraceptives.
Published online by Lancet this week, the WHO study supports the findings of previous studies. WHO, however, cautions women that the risk of developing cervical cancer is quite small. Timothy Farley, in the Department of Reproductive Health at WHO, noted that “People should not decide against the pill because of concerns about cervical cancer.” He added, “The benefits of the pill in terms of quality of life and preventing pregnancies far outweigh [the] risk.” According to Kaiser Daily Reproductive Health Reports, the overall risk for developing cervical cancer is only 1 percent in developed countries and 5 percent in the developing world.
One of the most common sexually transmitted infections in the United States, HPV can be asymptomatic. An estimated 5.5 million women will acquire an HPV infection every year, and an estimated 20 million are already infected, though the numbers may be larger. There are more than 60 strains of the virus, some of which can cause genital warts or lead to cervical cancer. Women should receive a pap smear annually to screen for HPV, which can be treated, and use condoms to prevent transmission.