Miami – Women who get intra-uterine devices (IUDs) for birth control appear to face a dramatically lower risk of getting cervical cancer, the third most common cancer in women worldwide, US researchers said Tuesday.

The risk of cervical cancer in women with IUDs was one-third lower than women without them, said the review in the journal Obstetrics and Gynecology, which included 16 previous studies spanning more than 12,000 women around the globe.

Researchers are not sure why the risk of cervical cancer drops so much, but one theory is that the devices stimulate an immune response that helps fight off cancer-causing infections like the human papillomavirus (HPV).

“If we can demonstrate that the body mounts an immune response to having an IUD placed, for example, then we could begin investigating whether an IUD can clear a persistent HPV infection in a clinical trial,” said co-author Laila Muderspach, chair of obstetrics and gynecology at the Keck School.

© AFP JAY DIRECTO A health worker teaches women how to properly use a intra uterine device (IUD) during the World Population Day in Manila July 11, 2008

© AFP JAY DIRECTO – A health worker teaches women how to properly use a intra uterine device (IUD) during the World Population Day in Manila July 11, 2008