A recent study states that women who use birth control pills have an increased risk of developing cervical cancer. Although the risk does fall once the pill is stopped—the risk returns to that of “never-users” within ten years of stopping—taking oral contraceptives for five or more years was associated with a doubling of cervical cancer risk.
The study results originated from new data analysis from 24 global studies and is considered “one of the most rigorous examinations of cervical cancer risk in oral contraceptive users ever conducted,” according to WebMD. The analysis of published and previously unpublished data involved over 16,500 cervical cancer patients and 35,500 women who were never diagnosed with cervical cancer. Epidemiologist Jane Green, MD, study lead, said, “We have known that women on the combined estrogen pill are at increased risk [for cervical cancer]. What we haven’t known is what happens after they stop taking the pill.”
Routine cervical cancer screening in developed countries—such as the United States—has led to marked decreases in ovarian cancers. For instance, for 1,000 women in more developed countries who use the pill are between the ages of 20 and 30, the researchers estimated that less than one extra cancer—4.5 in women who take the drugs versus 3.8 for never-users—can be expected by age 50. Conversely, in less developed countries, the risk was estimated to be 8.3 cases per 1,000 decade-long oral contraceptive users versus 7.3 cases for every 1,000 women who never took oral contraceptives.
The sexually transmitted human papillomavirus—HPV—is one of the major and most preventable risk factors for cervical cancer. Having multiple childbirths is also considered a risk for cervical cancer. Because of this, when looking at risks related to oral contraceptive use, a review of whether women gave birth to fewer babies because of the drug must also be conducted, according to Peter Sasieni, PhD, of London’s Wolfson Institute for Preventive Medicine. Also, because oral contraceptive use reduces a woman’s risk of developing ovarian and endometrial cancer, Sasieni and Green agree that the drug’s benefits may outweigh the risks for most women. Regardless, “Regular screening is important for all women, but especially for those taking oral contraceptives,” Sasieni says. Symptoms of cervical cancer include painful sex, vaginal bleeding, and discharge.
HPV infection of the cervix is a sexually transmitted disease—or STD. Because the virus may remain in the body for life, a prior HPV infection in the patient or her partner can cause abnormal cervical cell changes years later. Because HPV infection usually does not cause symptoms and often resolves without causing any problems, women and their partners may not be aware of a current or past HPV infection. Cervical cancer risks also include having an impaired immune system, such as what is seen in women with HIV (human immunodeficiency virus); being exposed to DES (diethylstilbestrol) before birth; and having a history of smoking or being exposed to second-hand smoke.