About Cancer generously supported by Dangoor Education since Some studies have shown smoking increases the risk of anal cancer. If you are curious about exploring anal sex, the key to keeping it safe and pleasurable is following some simple guidelines. SheKnows is making some changes! Sex from A-Z Cards: Find out more about the HPV virus. Factors that cause inflammation in the rectum of a person with HIV may increase the viral load in the rectal fluid but not in the blood and subsequently increase the risk of HIV transmission to an HIV-negative insertive partner.