1. Predisposing Factors/Risk Factors

​​​​Updated May 2026

​Cervical cancer continues to be a public health concern in Canada and British Columbia. It was estimated that 1,600 Canadians will be diagnosed with cervical cancer in 2024, with approximately 400 deaths expected1. In British Columbia, the lifetime risk for developing cervical cancer is about 1 in 170, and the age-standardized incidence rate has decreased from around 19 per 100,000 in the 1970s to approximately 7 per 100,000 today2. These statistics highlight the impact of organized cytology-based screening since the 1950s and the ongoing transition to primary HPV testing.

Cervical cancer can largely be prevented through HPV vaccination and regular screening. Persistent infection with high-risk human papillomavirus (HPV) types, particularly types 16 and 18, is the primary cause of cervical dysplasia and cervical cancer. The most common histologic types of cervical cancer are squamous cell carcinomas, which arise in the ectocervix (70%), and adenocarcinomas or adenosquamous carcinomas arising in the endocervical canal (25%)3.

Known risk factors

Human papillomavirus (HPV): 

Persistent infection with high-risk HPV genotypes is the leading cause of cervical cancer. HPV-16 and HPV-18 account for most cervical cancers globally4. HPV infection is sexually transmitted, and most people will be infected with HPV at some point in their lives. Females who have not participated in cervical cancer screening or who have less access to screening programs face greater risk for cervical cancer5.​

Smoking: 

Cigarette smoking is a recognized co‑factor in cervical carcinogenesis6. Carcinogens from tobacco accumulate locally in the cervical epithelium, cause DNA damage, and suppress immune defences –​reducing HPV clearance and enabling persistent high‑risk HPV infection, which promotes progression to cervical precancers and invasive carcinoma.​ 

Immunosuppression: 

Individuals with compromised immunity—such as those with HIV infection, organ transplant recipients, or patients on long-term immunosuppressive therapy—are at significantly increased risk of persistent high‑risk HPV infection and associated cervical dysplasia7,8. Their impaired immune surveillance reduces HPV clearance, leading to elevated rates of CIN and invasive cervical cancer.

Diethylstilbestrol (DES): 

Females exposed to DES in utero ("DES daughters") have an elevated risk of clear cell adenocarcinoma of the cervix and vagina9. They may also be at higher risk of squamous lesions if infected with HPV10. Individuals with a known history of in utero DES exposure should undergo annual co-testing (HPV and cytology) with colposcopic examination until age 69. 

Possible risk factors

Sexually transmitted infections (STIs): 

Past or current infections such as Chlamydia trachomatis and lower genital tract herpes simplex virus type 2 (HSV-2) have been associated with increased risk of cervical cancer, although their causal roles are less clear than that of HPV11,12.

Prevention

HPV vaccines:

Vaccination is an effective primary prevention strategy against HPV-related cancers. In British Columbia, the nonavalent HPV vaccine (HPV9, Gardasil®9) is provided free through the school-based immunization program to all Grade 6 students (regardless of biological sex or gender).

As of July 31, 2025, the HPV vaccine is indicated (and publicly funded) for individuals:

  • 9-26 years of age (inclusive)
  • 27-45 years of age (inclusive) who self-identify as belonging to the gay, bisexual, and other men who have sex with men (GBMSM) community (including those who are not yet sexually active and/or questioning their sexual orientation). This includes cisgender men as well as individuals who are Two-Spirit, transgender and/or non-binary
  • 9-45 years of age (inclusive) living with HIV
  • Who received treatment for cervical dysplasia on or after July 31, 2025
  • Note that those not eligible for publicly funded HPV vaccine can purchase it at most pharmacies and travel clinics.

The most up to date information on vaccine recommendation and coverage can be found here: https://www.bccdc.ca/health-profession​als/clinical-resources/vaccines-in-bc.

Vaccination is recommended ideally before the onset of sexual activity. Even those who are sexually active can benefit, as they may not yet have been exposed to all vaccine-covered HPV types.

Gardasil®9 protects against nine HPV types, including types 16, 18, 31, 33, 45, 52, and 58 (oncogenic), as well as types 6 and 11 (which cause genital warts). HPV4 and HPV2 vaccines have also been used in Canada but have been replaced by HPV9 in provincial programs.

Vaccinated individuals still require regular cervical screening, as the vaccine does not cover all oncogenic HPV types.

HPV vaccines are safe and highly effective. Adverse effects are rare and usually mild (e.g., soreness at injection site). For more information about vaccine eligibility, dosing schedules, and access, refer to ImmunizeBC (https://immunizebc.ca/).  

References​

  1. Cervical Cancer Statistics. Canadian Cancer Society. (https://cancer.ca/en/cancer-information/cancer-types/cervical/statistics).
  2. BC Cancer Cervix Screening Program Results Summary. BC Cancer Cancer Cervical Screening Program. (https://www.bccancer.bc.ca/screening/Documents/Cervix-Program-Results-2020.pdf).
  3. Stolnicu S., Soslow R.A.​. Squamous and Glandular Epithelial Tumors of the Cervix: A Pragmatical Review Emphasizing Emerging Issues in Classification, Diagnosis, and Staging. Surgical Pathology Clinics 2022;15(2):369–388. DOI: 10.1016/j.path.2022.02.010.
  4. Cervical cancer. WHO (World Health Organization). (https://www.who.int/news-room/fact-sheets/detail/cervical-cancer).
  5. Booth A., Pollard K., Dick A., et al. Cervical screening in BC--Change inspired by First Nations and Métis communities. British Columbia Medical Journal 2024;66(10).
  6. Castle P.E. How does tobacco smoke contribute to cervical carcinogenesis? J. Virol. 2008;82(12):6084–5; author reply 6085–6. (In eng). DOI: 10.1128/jvi.00103-08.
  7. Nailescu C., Ermel A.C., Shew M.L. Human papillomavirus-related cancer risk for solid organ transplant recipients during adult life and early prevention strategies during childhood and adolescence. Pediatric Transplantation 2022;26(7):e14341. DOI: https://doi.org/10.1111/petr.14341.
  8. Kaplan J.E., Benson C., Holmes K.K., et al. Guidelines for prevention and treatment of opportunistic infections in HIV-infected adults and adolescents. MMWR Recomm. Rep. 2009;58(4):1–207.
  9. Wamakima B.W., McKinney S., Bookman L., Gompers A., Hacker M.R., Farid H. Postmenopausal Vaginal and Cervical Cancer Risk Related to In Utero Diethylstilbestrol Exposure. J. Low. Genit. Tract Dis. 2023;27(1):35–39. (In eng). DOI: 10.1097/lgt.0000000000000713.
  10. Hoover R.N., Hyer M., Pfeiffer R.M., et al. Adverse health outcomes in women exposed in utero to diethylstilbestrol. N. Engl. J. Med. 2011;365(14):1304–14. (In eng). DOI: 10.1056/NEJMoa1013961.
  11. Kwaśniewska A., Korobowicz E., Zdunek M, et al. Prevalence of Chlamydia trachomatis and herpes simplex virus 2 in cervical carcinoma associated with human papillomavirus detected in paraffin-sectioned samples. European journal of gynaecological oncology 2009;30(1):65–70.
  12. Zhang H., Cai S., Xia Y., et al. Association between human herpesvirus infection and cervical carcinoma: a systematic review and meta-analysis. Virology Journal 2023;20(1):288. DOI: 10.1186/s12985-023-02234-5.​​