When women are exposed to genital human papillomavirus (HPV), their immune systems usually prevent the virus from doing serious harm. But in a small number of women, the virus survives for years. Eventually, the virus can lead to the conversion of normal cells on the surface of the cervix into cancerous cells.

At first, cells may only show signs of a viral infection. Eventually, the cells may develop precancerous changes. This is known as cervical intraepithelial neoplasia, which usually goes away spontaneously, but in some cases may progress to invasive cervical cancer.

It's not clear why some women are more likely to develop cervical cancer. Some types of HPV are simply more aggressive than are others. Cigarette smoking, being overweight, and long-term use of oral contraceptives also increase the risk of cervical cancer.

There are three HPV vaccines available — Cervarix, Gardasil and Gardasil 9. They offer protection from several of the most dangerous types of HPV.

If you're sexually active, the best way to prevent HPV and other sexually transmitted infections is to remain in a mutually monogamous relationship with an uninfected partner. Otherwise, when you have sexual intercourse always have your partner use a condom. Regular cervical screening is important, too.

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Aug. 24, 2016 See more Expert Answers