Here’s What Men and Women Really Think of Casual Sex

About half of all people in the United States and Western Europe will have at least one one-night stand, according to the authors of a new study. And how they feel about those encounters the next morning tends to vary based on gender: Women are more likely than men to regret casual sex, while men are more often happy with what went down.

The new research also saw big differences in how people felt after they turned down opportunities for casual sex: Very few women regretted saying no, while nearly a third of men wished they had said yes instead.

The findings, published in Evolutionary Psychology, come from a recent survey of 263 adults living in Norway, but they’re strikingly similar to previous research done in the U.S. In fact, the authors of the new study set out to see if they’d find big differences between the two locations, given that Norway has been ranked as a more sexually liberal, and secularized country.

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But it tuns out that the same patterns exist in both places. In the Norwegian survey, 35% of women regretted having sex with someone they’d just met, versus 20% of men. And only about 30% of women were happy about their most recent experience, versus 50% of men.

When asked about the last time they said no to casual sex, 80% of women and 43% of men were happy about their decision. Only about 4% of women regretted passing up an opportunity, compared to nearly 30% of men.

To figure out exactly why women tend to regret casual sex more than men, the researchers—from the Norwegian University of Science and Technology and the University of Texas at Austin—dug further. They found that, unsurprisingly, women tend to worry more about issues like pregnancy, sexually transmitted infections, and getting a bad reputation. Not only are some of these issues unique to women, the authors point out, but women tend to worry more in general—while men tend to be more impulsive and take more risks.

Survey respondents were also asked about sexual pleasure they received from their one-night stands. There, the researchers found another not-so-big surprise: Men had orgasms during casual sex far more often than women. At the same time, though, fewer women said that orgasm was particularly important.

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Still, the differences in worrying—or in sexual satisfaction—weren’t large enough to account for the overall gender gap in regret. Instead, the researchers hypothesize that regret has a lot to do with evolutionary differences between males and females.

Men are biologically programmed to produce as many offspring as possible, they say. Women, on the other hand, can’t have unlimited children the way men can—so they’re hardwired to care more about partners’ quality over quantity.

These biological drives are, of course, much less important today than they were centuries ago. And the researchers acknowledge that cultural stereotypes of sexually active men versus sexually active women may certainly play into women’s greater likelihood of having a negative experience. Women are also more likely to be coerced or pressured into sex than men, they write, which may also account for some instances of regret.

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But the fact that this pattern persisted, even in a sexually egalitarian culture like Norway, suggests that evolutionary biology still has an impact, the researchers wrote.

So are there any lessons to take away from this? Leif Edward Ottesen Kennair, PhD, professor of psychology at the Norwegian University of Science and Technology, says that in today’s relatively liberal society, people may be troubled if they feel bad after having casual sex—actually experiencing unhappiness because of their unhappiness.

“Some women might find some comfort in not being alone about regretting one-night stands, or not having orgasms every one-night stand,” Kennair told Health via email.

But it’s also important to note that these top-line results only show the big picture, he says. Plenty of women didn’t regret their one-night stands, just as plenty of men did. In other words, what really matters is how you feel about sex—not how society, or any one study, says you should feel.

After all, when both partners are into it, getting busy has been shown to have scores of health benefits. The important thing is that you’re using protection and making informed, safe decisions—ones that are good for you physically and emotionally.

This article originally appeared on Health.com