The common risk factors for cervical cancer are:
- Human papillomavirus (HPV) infection is the single most important risk factor which is found associated with almost all the cases of cervical cancer. Although the incidence of HPV infection is very common (about 50%) in women who become sexually active between the ages of 16 and 21 years but very few women with HPV infection ultimately develop pre-cancerous cervical lesions or invasive cervical cancer.
HPV is a group of about 150 DNA viruses with high-risk subtypes including HPV-16 and HPV-18 that are found in about 70% of all the cases of cervical cancer. Researchers believe that HPV consists of two proteins known as E6 and E7 which inactivate some tumor suppressor genes and lead to cervical cancer.
- Tobacco/Cigarette Smoking: Chronic tobacco chewing or cigarette smoking exposes the body to various carcinogens that suppress the immune system to fight against HPV infection and increase the risk of cervical cancer.
- Early coitus: Women who become sexually active at a younger age and had HPV infection are considered at high risk of developing cervical cancer.
- Early childbirth: Women who had a full-term pregnancy at an age younger than 17 years are more likely to develop cervical cancer than those who become pregnant after the age of 25 years.
- Multiple Childbirths: Women with 3 or more full-term pregnancies are at higher risk of developing cervical cancer which has been postulated to be due to the hormonal changes during pregnancy that make women more susceptible to HPV infection or cancer growth.
- Multiple sexual partners: Women who have multiple sexual partners or have partners with multiple partners are considered to be at higher risk of developing cervical cancer due to higher chances of sexually transmitted HPV infection.
- Prolonged use of oral contraceptives: Women who are using or who have used oral contraceptives for many years are generally at higher risk of developing cervical cancer.
- Weak immune system: Women with a weak immune system that may be due to any cause, for example, infection with human immunodeficiency virus (HIV), use of medicines that suppress the immune system, an autoimmune disorder, and others. A weak immune system renders women more prone to HPV infection and thus to the development of cervical cancer.
- Family history: Risk of developing cervical cancer increases in females with a history of cervical cancer in first-degree relatives (mother, daughter, or sister). The risk further increases with the increase in the number of affected relatives.
- Obesity: An increased body mass index or waist circumference has also been linked to increased incidence of cervical cancer, based on observations in many epidemiological studies.
- Socioeconomic status: Cervical cancer generally occurs in women of lower socioeconomic status or who belong to lower income group due to less access to healthcare services and cervical cancer screening.
Consumption of diet low in fruits and vegetables, in utero exposure to diethylstilbestrol (DES), history of a sexually transmitted disease, and chlamydial infection are other reported risk factors for cervical cancer.
Apart from the above-listed risk factors, certain factors which can reduce the risk of cervical cancer have also been reported. Such protective factors mainly include the use of intrauterine devices for birth control and HPV vaccination.