Cervical cancer begins with abnormal changes in the cervical tissue. The risk of developing these abnormal changes is associated with infection with human papillomavirus (HPV). In addition, early sexual contact, multiple sexual partners, and taking oral contraceptives (birth control pills) increase the risk of cervical cancer, because they increase exposure to HPV. Cigarette smoking (nicotine) increases the growth rate of HPV.
Forms of HPV, a virus whose different types cause skin warts, genital warts, and other abnormal skin disorders, have been shown to lead to many of the changes in cervical cells that may eventually lead to cancer. Genetic material that comes from certain forms of HPV (high-risk subtypes) has been found in cervical tissues that show cancerous or precancerous changes.
In addition, women who have been diagnosed with HPV are more likely to develop a cervical cancer. Girls who begin sexual activity before age 16 or within a year of starting their menstrual periods are at high risk of developing cervical cancer.
Cigarette smoking is another risk factor for the development of cervical cancer. The chemicals in cigarette smoke interact with the cells of the cervix, causing precancerous changes that may over time progress to cancer. The risk of cervical cancer in cigarette smokers is two to five times that of the general population.
Oral contraceptives (“the pill”), especially if taken longer than five years, may increase the risk for cervical cancer because they reduce the use of condoms.