Circumcision reduces the risk of HIV for men but it does not stop transmission of the virus to female partners, according to a new study.

Researchers in Uganda said Thursday circumcised men who already had virus do not stop risk for virus to their wives or female sex partners. They stopped the trial early because of the continued risk to women.

"We were disappointed that the trial did not show protection from HIV infection in women, as was expected from observational studies," Dr. Maria Wawer of Johns Hopkins University in Baltimore and colleagues in Uganda wrote in the Lancet medical journal.

"The trial was stopped early because of futility."

The study analyzed 922 uncircumcised, HIV-infected, men aged 15 to 49 years. Some were immediately circumcised and some had the procedure delayed for two years.

The researchers also followed 163 wives or female sex partners of these men.

"Circumcision of HIV-infected men did not reduce HIV transmission to female partners over 24 months; longer-term effects could not be assessed," Wawer's team wrote.

"Condom use after male circumcision is essential for HIV prevention."

Despite the findings, Wawer and colleagues suggest that women do benefit when men participate in circumcision programs.

"Reductions in male acquisition of HIV attributable to circumcision are likely to reduce women's exposure to HIV infected men," they say. "Male circumcision programs are thus likely to confer an overall benefit to women."

(Agency July 18, 2009)