Male circumcision continues to be a hotly debated topic. The practice of circumcision, most commonly performed for religious or cultural reasons, has been ongoing for thousands of years. Recently, however, there has been a growing backlash against infant circumcision in the United States and, in fact, between 1971 and 1983, the American Academy of Pediatrics formally advocated against the practice. The Academyâs position against circumcision was modified in 1989, however, after new clinical research data was published suggesting that circumcision significantly decreased the risk of acquiring the human immunodeficiency virus (HIV). However, in view of the historically non-medical basis for circumcision, and due to an increasing sensitivity on the part of both parents and physicians towards the discomfort that infants may experience during circumcision, this procedure continues to be the subject of considerable debate.
Three newly published studies in the Journal of Infectious Diseases add to the findings of previous studies suggesting that a potential clinical benefit may be associated with circumcision. Specifically, these new studies suggest that not only does male circumcision reduce the risk of acquiring HIV infection, but it may also significantly reduce the risk of infection with the human papilloma virus (HPV). Like HIV, HPV is a sexually transmitted virus, and several strains of the HPV virus are known to cause virtually all cases of cancer of the cervix in women, as well as many of the cases of cancers of the anal canal, oral cavity, and throat (in both men and women). Several HPV virus strains also cause genital warts in both men and women.
While chronic infection with cancer-causing HPV strains produces precancerous changes in women that can usually be detected during Pap smears, most infected males are asymptomatic. The FDA recently approved a human HPV vaccine, Gardasil, which provides protection against 4 strains of the HPV virus. Although not all cancer-causing strains of HPV are covered by Gardasil, the vaccine does provide protection against the HPV strains that, together, account for about 70 percent of all cervical cancer cases, and against more than 90 percent of all HPV-associated cases of genital warts. Because the vaccine is quite expensive, and because the vast majority of cancers caused by HPV occur in women, Gardasil is approved for use only in girls and young women between the ages of 9 and 26 years.
The three new studies presented in the Journal of Infectious Diseases compared the incidence of HPV and HIV infections in sexually active men with and without a prior history of circumcision. One of these studies prospectively assessed the effects of adult circumcision in young African men, and after 21 months of follow-up, the incidence of HPV infection was observed to be 34 percent lower in the men who had been randomized to undergo circumcision when compared to the men who did not draw the âcircumcision card.â The second clinical study was performed in the United States, and evaluated the incidence of HPV infection among circumcised and uncircumcised men. Among the 16 percent of men who had previously been circumcised, the incidence of HPV infection, after adjusting for a number of behavioral and demographic variables, the authors of this second study identified a 53 percent lower risk of HPV infection in the circumcised men when compared to the uncircumcised men.
In an accompanying editorial, both of these studies were criticized due to inherent weaknesses in both methodology and analysis, although the editor acknowledged that there may well be a protective effect of circumcision against HPV infection in males. As males act as both reservoirs and vectors in the transmission of HPV, the possibility that circumcision may decrease the incidence of HPV infection in men is intriguing. As prior studies have produced conflicting results regarding the protective effect, if any, of circumcision against HPV infection in men, we must await the results of two large prospective male circumcision trials ongoing in Africa before circumcision can be advocated for the purpose of reducing the incidence of HPV infections.
A third study in the Journal of Infectious Diseases adds to the already substantial body of research data confirming that male circumcision decreases the risk of HIV infection. In this third study, also performed in Africa, male circumcision reduced the risk of HIV infection in heterosexual African males known to be exposed to the virus by almost 50 percent, which is comparable to the findings of multiple prior studies that have looked at the impact of circumcision on HIV infection risk.
Taken together, these three studies add important information regarding the potential protective effects of circumcision against infections by the HPV and HIV viruses. While the jury is still out with respect to circumcision and the risk of HPV infection, the data showing that circumcision cuts the risk of HIV infection in half is quite robust. Because of these findings, the World Health Organization now advocates on behalf of male circumcision as part of a comprehensive strategy to prevent HIV infections. However, no research study has ever suggested that male circumcision can protect men (or women) against all cases of HIV infection, and so even if you are circumcised, you still need to adhere to established safe sex practices to protect yourself and your partner from infections with HIV, HPV and other sexually transmitted diseases.