According to an article recently published in The Lancet, the use of combined oral contraceptives (estrogen and progestin) temporarily increases the risk of cervical cancer. However, this risk remains small: one extra person per 1,000 is diagnosed with cervical cancer with use of the contraceptives.
The cervix is located at the bottom of the uterus. In developed countries, cervical cancer rates are low, due to regular screening with a PAP test to detects pre-cancerous changes to the cervix and early-stage cervical cancer, which is highly curable. Therefore, even among women who are diagnosed with cervical cancer, cure rates are high with standard therapies. However, in undeveloped countries where screening is not readily available, mortality rates from cervical cancer remain suboptimal.
Researchers are evaluating data that may help identify specific variables associated with increasing the risk of developing certain cancers. Individuals found to have a higher risk may benefit from additional screening.
Researchers affiliated with International Collaboration of Epidemiological Studies of Cervical Cancer recently evaluated data from 24 studies conducted worldwide to explore the association between cervical cancer and oral contraceptive use. This study included data from 16,573 women diagnosed with cervical cancer and 35,509 women without cervical cancer. Factors such as age, number of sexual partners, age at first intercourse, childbirth, smoking, and screening behaviors were also factored into the results.
- The risk of cervical cancer increased with longer use of oral contraceptives.
- The risk of cervical cancer decreased after the use or oral contraceptives was stopped.
- At 10 years of no oral contraceptive use, the risk of cervical cancer returned to that of the general population.
The researchers concluded that combined oral contraceptives increase the risk of cervical cancer with longer duration of use; however, this risk declines if a woman stops using the contraceptives. Furthermore, the risk is estimated to be, at the most, only one extra case of cervical cancer per 1,000 women. Women who seek birth control should speak with their physician regarding their individual risks and benefits of all available contraception options.
Reference: International Collaboration of Epidemiological Studies of Cervical Cancer. Cervical cancer and hormonal contraceptives: collaborative reanalysis of individual data for 16,573 women with cervical cancer and 35,509 women without cervical cancer from 24 epidemiological studies. The Lancet. 2007; 370:1609-1621.