The arithmetic has never quite make sense to researchers: On average, men report that they’ve had far more sexual partners than women do. Since, mathematically speaking, the sexes should report roughly the same number of past partners, it’s always been a bit of a mystery why there’s such a discrepancy. A new study in The Journal of Sex Research finds some explanations for the inconsistency, which, the authors write, “has long vexed researchers and has underpinned concerns about the veracity of self-reported sexual behavior in general.”
The team from the University of Glasgow wanted to explore the discrepancy with a healthy diverse sample of people. Earlier studies had often used students only or high-risk populations, so it’s been hard to tell how the general population compares. They used data from 15,000 people, aged 17 to 74, who answered questions about their past sexual partners. It found, as others have, that men reported many more than women: 14 partners on average, while women reported only seven. But it also looked at the variables that contribute to this discrepancy.
One reason behind the dichotomy is that men who reported high numbers reported extremely high numbers—that is, men in the 99th percentile of sexual partners reported 110 past partners, where women’s highest numbers were just 50. Taking these outliers out of the equation reduced the gender gap somewhat.
Another force contributing to the gap was the accounting strategies men and women tended to use. Women were more likely to actually tally up the exact number than men were—men were more likely to estimate, especially when their numbers were higher. But they even estimated more frequently when their numbers were lower. Their reports were also more likely to end in a 5 or a 0, especially when the number of partners they reported having was higher, which again suggests there may be some (over)estimating and rounding going on.
The third factor seemed to be the genders’ attitudes both toward one-night-stands and cheating on a spouse: Men were significantly less likely to believe either was always wrong, which could account for their reporting higher numbers.
So it seems like there may be a couple of things at play: Men may actually have more sexual partners than women do, but they may also inflate the number by estimating or rounding more often than women. The authors do point out that the gender gap has decreased slightly in recent years, which may reflect changing attitudes about sex, which, they say, are “more gender equal and tolerant of diversity.” But the mechanisms outlined in the paper help explain why the remaining gender gap does exist.
The results might also influence how surveys are written, to get people to give the most accurate estimates about their sexual histories, without coming off as judgy. But for the rest of us, the study just provides some interesting insight into differences in the sexes—and how they may view and remember sex differently.