Americans are having less sex, whether they’re teenagers or in their 40s.

One of the most comprehensive sex studies to date — the National Survey of Sexual Health and Behavior — found evidence of declines in all types of partnered sexual activity in the U.S. Over the course of the study from 2009 to 2018, those surveyed reported declines in penile-vaginal intercourse, anal sex and partnered masturbation.

So what’s behind this decline in sex? Is it that we’re too busy, depressed or just becoming more evolved?

The study itself didn’t look into the reasons for the decline in sexual behavior, but researchers are starting to explore what may be driving it.

To start, the lead researcher behind this study says we have to look at teenagers.

While today’s adolescents are armed with more language — for instance, they’re more likely to express their gender pronouns and sexual identity — overall they are delayed in a number of things, including sexual expression, says Debby Herbenick, who also teaches at the University of Indiana Bloomington.

“People who study adolescence and adulthood, many of us have seen an overall delay, right?” she says. “Like teenagers are taking longer now to get their first driver’s license. So it’s not even just about sex. Like there’s not as much drinking alcohol.”

Over the last 22 years, Herbenick has co-authored several studies about our sexual activity. Her most recent research finds that all of us, regardless of age, are having less sex, with the most dramatic decline among teenagers.

At the start of the study in 2009, 79% of those ages 14 to 17, revealed they were not having sex. By 2018, that number rose to 89%.

Another reason for the decline in sex: People are becoming more open talking about their sexuality and how much — or how little — sex they’re having. Herbenick says this is new for our culture.

In her classrooms, she says she has seen more college-aged students openly expressing their sexuality outside of the binary of gay or straight. A growing number of people are also openly identifying as asexual, which means having little or no sexual desire.

“With greater comfort in connecting to asexual identities, there is a small, but still meaningful percent of people then who can also feel some comfort in asserting, ‘I’m not interested actually in partnered sex,’ ” Herbenick says.

Herbenick’s team has several more studies underway right now to get a deeper understanding of how much cultural shifts like this are impacting the decline in sexual activity.

On the other side of that coin, one finding Herbenick is especially interested in exploring is the increase in rough sex. In this latest study, a significant number of those ages 18 to 29 have reported experiencing things like punching and choking during intimate activity. This is happening to many young people during their earliest sexual experiences, she says.

“They’re hooking up with this person they’re really into, and suddenly that person hits them or punches them, or maybe they even ask to be hit, but they think it’s going to be a light, little playful slap and they just get walloped,” she says. “And so I think what I see as somebody who’s been in this field for 20 odd years now, is that the tone of those early experiences … I don’t know why you go back for more.”

With all of these factors in mind, should we be worried?

Herbenick says no. Even though we know sex can improve health, quality of life and our desires to reproduce, taking ownership of when we want it, how we want it and whether we want to participate in it at all is just as important.

“Just being able to say, ‘No, I’m not into it.’ And that’s OK. People don’t have to live up to some frequency,” Herbenick says. “As long as I’ve been in this field, I’ve fielded questions from journalists who have wanted us to say what is the right number or the healthy number of times a week or a month somebody should be having sex?

“And we’ve always said there is no such number,” she says. “So I think for everybody, what I hope greater information about sexuality can do is to help them feel some liberation from things that have otherwise penned them in.”

This article was originally published on WBUR.org.

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