Two gay guys have sex without a condom and it’s called a subculture. A mixed–HIV status straight couple does the same and it not only flies beneath the media radar, it’s just a statistic. Two-thirds, to be exact—the proportion of serodiscordant hetero duos who said they’d had condomless sex in the past six months, according to a new study. Researchers at the University of California at San Francisco asked 104 couples how often they used condoms when they had vaginal or anal sex. About 70 percent reported having unprotected vaginal intercourse, and of the 57 people who said they’d had anal sex in the last six months, about two-thirds did so without condoms.

One HIVer, “Skip,” said that he and his HIV negative girlfriend of more than a year had started out using female condoms. “But we were getting so involved in each other,” Skip said, that they soon settled on a compromise: “I never ejaculate in her.” The couple, both in their 40s, said that despite the anxiety that accompanies regular testing by Skip’s girlfriend, in some ways having unprotected sex has improved their relationship. “We both know the consequences,” he said. “It’s more open.”

Linda Simon, the clinical director at Positive Connections, a Miami-based group for hetero HIVers, said that Skip’s experience and the study results echo what she’s heard when she has led support groups for couples. “For those in new relationships, there is a conscientiousness of wearing some protection,” said Simon, a certified sex therapist. “But as the relationship progresses, I think they get lax.” Simon said that another group—people already in long-term relationships when one tests positive—are abstinent at first, but as they learn more about HIV, they start having oral sex again and then protected intercourse.

The gender of the positive partner is a major factor: Simon said that in general when the woman is positive, men are more relaxed about using protection, whereas if the man is positive, the woman is often likely to insist on using it. And, unlike their male partners, Simon sai

“I can’t say this choice is for everybody,” Skip said. “But I do think people should sit down and talk about it, because it’s a two-party thing.”