“Among HIV-negative sexual partners, male circumcision helps prevent the transmission of human papillomavirus [HPV] from men to women,” according to a study published online Thursday in the Lancet, HealthDay News/Bloomberg Businessweek reports. “However, circumcision offers only partial protection and partners must still practice safe sex, the researchers pointed out,” according to the news service (1/6).

Among other things, HPV infection can lead to cervical cancer in women, according to the the authors of the study. “More than 85% of the HPV disease burden is in developing countries, and cervical cancer is the leading cause of cancer mortality in women in east Africa,” they wrote. Though previous studies showed that male circumcision can protect men from HIV/AIDS and HPV, whether male circumcision protected women from HPV was previously unknown (Wawer et al., 1/7).

For the study, researchers “analyzed data from two clinical trials in Uganda that followed HIV-negative men and their HIV-negative female partners between 2003 and 2006,” HealthDay News/Bloomberg Businessweek continues (1/6). The researchers “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,” Reuters reports. “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,” the news service adds (Fox, 1/6).

Incidence of high-risk HPV infection, those infections that could lead to cancer, “was 23 percent lower for women with circumcised partners than for those with uncircumcised partners, the investigators found,” HealthDay News/Bloomberg Businessweek adds (1/6). “Along with previous trial results in men, these findings indicate that male circumcision should now be accepted as an efficacious intervention for reducing heterosexually acquired high-risk and low-risk HPV infections in men who do not have HIV and in their female partners,” the authors of the study write, according to according to a Lancet press release. “However, our results indicate that protection is only partial; the promotion of safe sex practices is also important,” the add (1/6).

As MedPage Today reports, the authors note “the study did not assess cervical neoplasia directly,” which is the presence of abnormal cervical cells. Additionally, the researchers “cautioned that [due to the fact the] men and women in the study were in stable relationships and did not have HIV at baseline, … the results may not apply to other populations. The analysis may also have underestimated incidence, they cautioned, because infections acquired and cleared between the yearly follow-up points would have been missed,” the news service writes (Smith, 1/6).

Still, the “findings add important evidence for the promotion of male circumcision in countries without well-established programmes for cervical screening,” wrote the authors of an accompanying Lancet Comment. “Additional interventions to reduce HPV infection, such as provision of vaccines for HPV prevention, will be essential to reduce invasive cervical cancer worldwide. Male circumcision is associated with slight reductions in high-risk HPV, while licensed HPV vaccines protect with high effectiveness against only a limited number of HPV types. Therefore the two interventions are likely to have important synergistic effects” (Giuliano et al., 1/7).