There is growing controversy about the benefits of birth control pills also known as oral contraceptives. Birth control pills contain the sex hormones estrogen and progesterone. Medical studies show an increase in cases of cervical cancer among women who have used oral contraceptives for extended periods.
The most significant observations are in women who have used oral contraceptive hormones for five years or more. Pap smear results on these women show significant changes in the cells of the cervix.
Some evidence indicates that progesterone can decrease the effectiveness of the body’s immune system. Decreased immunity increases the risk of infections by bacteria and viruses, such as human papillomavirus (HPV), the leading risk factor for cervical cancer.
Long-term use of birth control pills might also be responsible for altering genes that help keep HPV infection at bay. Medical researchers have discovered that the presence of sex hormones enhances the ability of HPV to replicate. However, HPV alone does not always lead to cervical cancer. Recent preliminary studies in mice show that HPV infection combined with the use of sex hormones, specifically estrogen, significantly increases the chances of developing squamous cell carcinoma of the cervix. The incidence of cervical cancer increases with the length of time oral contraceptives are used.
In addition to the direct hormonal effects listed above, many experts believe that the increased cancer risk related to oral contraceptive use may simply be related to less safe sexual practices. In general, women who take the pill are less likely to use a condom, thus increasing their exposure to HPV and other STDs.
When HPV is not present, the benefits of taking birth control pills outweigh the risks. Early detection is the best prevention. Regularly scheduled Pap smears, every one to three years, will help to detect early signs of the disease, when cervical cancer treatment is most effective.
Moodley, M., Moodley, J., Chetty, R., Herrington, C. (2003, March). The role of steroid contraceptive hormones in the pathogenesis of invasive cervical cancer: A review. International Journal of Gynecological Cancer, 13(2), 103-110.
National Cancer Institute.(updated 2003). Oral contraceptives and cancer risk. Retrieved August14, 2003, from www.cis.nci.nih.gov/fact/3_13.htm#cervix.