A risk factor is any factor that is associated with increasing someone’s chances of developing a certain condition, such as cancer. Some risk factors can be modified, such as lifestyle or environmental risk factors, and others cannot be modified, such as inherited factors or whether someone in the family has had cancer.

Having 1 or more risk factors does not mean that a person will develop cancer. Many people have at least 1 risk factor but will never develop cancer, while others with cancer may have had no known risk factors.

Even if a person with cancer has a risk factor, it is usually hard to know how much that risk factor contributed to the development of their disease.

Vaginal cancer risk factors

Risk factors for vaginal cancer including:

• human papillomavirus (HPV) infection
• exposure to diethylstilboestrol (DES) in the womb
• untreated pre-cancerous vaginal intraepithelial neoplasia (VAIN); the level of risk depends on what the biopsy looks like down a microscope
• previous cervical cancer or pre-cervical cancer
• previous radiation therapy to the pelvic area
• smoking tobacco
• age – it is more common in women who are over 70 years old.

HPV infection

HPV is a common infection affecting the skin surface of any part of the body, including the vagina and the cervix. More than 100 types of HPV have been identified, but about 12 are considered high risk because they can lead to cancer.

HPV is infectious – it spreads from person to person through genital skin contact. Around 8 out of 10 women will become infected with genital HPV at some time in their lives. It is so common that it could be considered a normal part of being sexually active.

However, vaginal cancer is not infectious.

HPV does not often cause symptoms, so many people are unaware they have the virus. For about 98% of women, the virus is cleared rapidly by the immune system.

HPV can cause precancerous cells that may be found during a routine cervical screening test.

Diethylstilboestrol (DES)

DES is a drug that was given to some women from the 1940s to the early 1970s to prevent miscarriage and other pregnancy-related complications. Daughters whose mothers took DES have an increased risk of developing some cancers, including vaginal cancer.

Vaginal intraepithelial neoplasia (VAIN) risk factors

VAIN is relatively uncommon, but it appears to be more likely in women who:

• smoke tobacco
• have had human papillomavirus (HPV) infection
• have suppressed immune systems
• have had surgery for cervical precancerous lesions
• have had radiation therapy in the pelvic region
• have had vulval intraepithelial neoplasia (VIN)
• were exposed as a foetus to a hormone medication called diethylstilboestrol (DES)
• have had an abnormal cervical screening test result but the cervix is normal.