In 2005, a research study at the College of Malmö in Sweden suggested that performing unprotected oral sex on a person infected with HPV might increase the risk of oral cancer. The study found that 36 percent of the cancer patients had HPV compared to only 1 percent of the healthy control group.
Another recent study suggests a correlation between oral sex and head and neck cancer. It is believed that this is due to the transmission of human papillomavirus (HPV), a virus that has been implicated in the majority of cervical cancers and which has been detected in throat cancer tissue in numerous studies.
The New England Journal of Medicine study concluded that people who had one to five oral-sex partners in their lifetime had approximately a doubled risk of throat cancer compared with those who never engaged in this activity and those with more than five oral-sex partners had a 250% increased risk
