CHICAGO—Two new studies suggest that adult male circumcision may reduce the risk of HIV transmission without reducing pleasure or causing sexual dysfunction.
In a study of 10 circumcised and 10 uncircumcised men, Australian researchers showed that the inner foreskin of the penis has a significantly higher density of Langerhans cells—the initial cellular targets in the sexual transmission of HIV—than other areas of the foreskin.
By removing the inner foreskin, circumcision removes the skin surface that is most susceptible to HIV infection, thereby reducing the risk of contracting HIV. The researchers found no differences in epithelial or keratin thickness between the remnant foreskin, inner foreskin, or shaft skin.
“There is a biological reason for mass circumcision to be protective against the transmission of HIV. We think that is because of decreased HIV target cells left after circumcision,” study investigator Sandra Hallamore, MD, a urology resident at the University of Melbourne, told Renal & Urology News.
In the other study, investigators in the United States and Kenya found that circumcised men had a significantly lower risk of coital injuries (bleeding, scratches, cuts, abrasions, or “getting sore”) compared with uncircumcised men. Such injuries could enable HIV transmission. Circumcised and uncircumcised men showed no difference in sexual function.
The study involved 2,784 Kenyan men aged 18-24 years who were divided into two groups. One group consisted of men who would be circumcised within 30 days of study randomization; the other group served as controls. Detailed evaluations were performed at one, three, six, 12, 18, and 24 months after circumcision.
“Adult male circumcision is protective against sexually acquired HIV infections,” said study investigator Supriya Mehta, PhD, MHS, Assistant Professor of Epidemiology at the University of Illinois at Chicago.
“There is no harm in terms of an association with sexual dysfunction.” The finding that circumcision results in reduced risk of injury to the penis during sexual intercourse was unexpected, she said.
The two studies add to the body of scientific evidence showing that adult circumcision is an important tool for HIV prevention, Dr. Mehta said.
The findings were presented here at the American Urological Association Annual Meeting.
These studies “could point the way to the first surgical approach ever to an infectious epidemic,” said urologist Ira Sharlip, MD, a specialist in sexual medicine at Pan Pacific Urology in San Francisco.
He added that the studies “support the concepts that circumcision does not interfere with sexual function and that circumcision is an important element of HIV prevention in sub-Saharan Africa. At the same time, it should be emphasized that circumcision must be combined with other techniques of HIV prevention, such as safe sex and voluntary testing. It is not sufficient to rely on circumcision alone to prevent HIV transmission.”