In your paper, you bring up increases in “rough sex” as potentially contributing to declines. Can you explain what you mean by rough sex, and how it could be playing a role in these changes?

HERBENICK: Especially for those 18 to 29 years old, there have been increases in what many people call rough sex behaviors. Limited research suggests that an earlier idea of this was what I would consider fairly vanilla rough sex: pulling hair, a little light spanking. What we see now in studies of thousands of randomly sampled college students is choking or strangling during sex. The behavior seems to be a majority behavior for college-age students. For many people, it’s consensual and wanted and asked for, but it’s also scary to many people, even if they learn to enjoy it or want it. It’s a major line of research for our team: to understand how they feel, what the health risks are and how that fits into the larger sexual landscapes.

FU: We have seen what seem to be real shifts in those behaviors. We don’t know to what extent that may be driving some people to opt out, but we do know that some people are feeling frightened and don’t know what to make of what’s being presented to them, especially young adults. They could consent to sex, but something like choking might happen without them being asked before. We see a lot of gender effects in a lot of behaviors for different nonheterosexual identities. For example, bisexual women experience a lot more of these aggressive behaviors.