Researchers have documented yet another health benefit for circumcision, which can protect men against the AIDS virus, saying it can protect their wives and girlfriends from a virus that causes cervical cancer.
Wives and girlfriends of circumcised men had a 28 percent lower rate of infection over two years with the human papilloma virus or HPV, which causes warts and cervical cancer, they reported in the Lancet medical journal on Thursday.
"Our findings indicate that male circumcision should now be accepted as an efficacious intervention for reducing the prevalence and incidence of HPV infections in female partners.
However, protection is only partial; the promotion of safe sex practices is also important," Dr.Maria Wawer and colleagues at Johns Hopkins University in Baltimore wrote.
Wawer's team piggybacked the HPV study onto a larger study that has shown circumcised men are less likely to be infected with the human immunodeficiency virus that causes AIDS.
"We enrolled HIV-negative men and their female partners between 2003 and 2006, in Rakai, Uganda," they wrote in their report in the Lancet medical journal.
They were able to get details on HPV infections for nearly 1,000 of the women, all identified by men as long-term sex partners such as wives. After two years, 27.8 percent of the steady partners of circumcised men had HPV infections, compared to 38.7 percent of the partners of uncircumcised men.
HPV infection is best known as the primary cause of cervical cancer, but it causes genital warts and can also lead to cancers of the anus, penis, head and neck.
There are dozens of strains of HPV, which are highly contagious and which infect the majority of the population within a few years of beginning sexual activity. Most people clear the virus but in some, it can cause changes that lead to cancer.
Cervical cancer is the second most common cancer in women worldwide and is expected to kill 328,000 this year, mostly in developing countries.
GlaxoSmithKline and Merck make vaccines against HPV but they are not available to most women in developing countries.
Circumcision removes the foreskin of the penis, which is rich in immune system cells targeted by HIV and perhaps other viruses. Taking off the foreskin likely makes the penis less likely to carry a range of microbes, Wawer's team said.
"Male circumcision has now been shown to decrease HIV, herpes simplex virus-2, and HPV infections and genital ulcer disease in men, and also HPV infection, trichomoniasis, and bacterial vaginosis and genital ulcer disease in their female partners," Wawer's team wrote.
"Thus, male circumcision reduces the risk of several sexually transmitted infections in both sexes, and these benefits should guide public health policies for neonatal, adolescent, and adult male circumcision programs."