How could male circumcision protect against HIV?

Male circumcision is the surgical removal of all or part of the foreskin of the penis. There are several biological explanations at to why this operation may reduce the risk of HIV infection.

Removal of the foreskin reduces the ability of HIV to penetrate the skin of the penis. In addition, on the underside of the foreskin are located many special immunological cells such as Langerhans cells which are prime targets for HIV. Another possible explanation is that small tears in the delicate skin of the inner surface of the foreskin during sexual intercourse could allow a portal of entry for HIV. Men with a foreskin are more prone to have some infections, including sexually transmitted infections, which can enhance HIV transmission.

Male circumcision is associated with a much lower risk of penile cancer. Several studies now suggest that female partners of circumcised men have a lower risk of cancer of the cervix.

Other benefits include prevention of inflammation of the glans and foreskin (balanitis) and prevention of scar tissue causing an inability to retract the foreskin (phimosis).