Men who have unprotected anal sex with other men may not be more likely to arrange the sexual encounters through the Internet than through other venues, a new federal study suggests.

The research, sponsored by the U.S. Centers for Disease Control and Prevention (news - web sites) (CDC), also showed that disclosure of HIV (news - web sites) status among men who have sex with men (MSM) is more common in online-initiated encounters.

The findings were reported Friday at the 12th Annual Conference on Retroviruses and Opportunistic Infections in Boston.

A team led by Dr. Mary Chiasson, of the Medical and Health Research Association of New York City, studied 1,707 MSM from the United States and Canada who had sex in the previous three months with a new or casual partner. Participants in the study answered questions online about their most recent sexual encounter, during which 28 percent reported unprotected anal intercourse (UAI).

Of the men whose last encounter involved UAI with a single partner, 30 percent met the partner online, versus 25 percent meeting elsewhere. The men in this group were also more likely to disclose their HIV status to partners they met online than to those they met offline (53 percent versus 35 percent).

Of those reporting recent UAI with multiple partners during their most recent sexual encounter, 25 percent arranged it online, while 32 percent arranged it offline. These men were also more likely to disclose their HIV status with partners they met online (57 percent) versus offline (45 percent).

Jason Riggs, communications director for the San Francisco-based Stop AIDS (news - web sites) Project, noted that the study appears to contradict earlier research about online vs. offline sexual habits, and the agency is still reviewing the findings. He welcomed, however, the statistics about HIV disclosure.

"People who feel comfortable enough to disclose their HIV status, positive or negative, to potential partners is a gold standard in HIV prevention," Riggs said. "That kind of environment needs to be encouraged in the community, both online and off."

"It is not surprising that the anonymity of the Internet allows many HIV-positive men an opportunity to disclose their status without the same fear of rejection that they might face in person," said Noel Alicea, spokesman for the Gay Men's Health Crisis (GMHC) in New York. "The Internet allows for frank and open dialogue that is not always afforded in other spaces."

PlanetOut Inc., owner of Gay.com and PlanetOut.com, makes safer-sex resources available on its sites and in chat rooms.

Alicea added that GMHC plans to increase its presence in online chat rooms and sex sites: "It has become clear that the Internet provides us with new opportunities to have honest conversations with men who are interested in sexual health."