How Many Past Sexual Partners Is Too Many?
As I outlined in a previous post, the modern mating market is very different from our ancestral past. For thousands of generations, mating options for humans were quite limited. There were fewer prospective partners, parents and family had more of an influence over mate choice, and anonymity was low. Today, particularly in cities and online, mating becomes a trial-and-error process of searching through an overwhelming number of potential suitors.
One consequence is that the number of sexual partners we can amass has increased considerably. Historically, even the most prolific lover would only need their hands to count the number of people they’d been intimate with. Today, if they’re committed to the cause, an attractive person could sleep with hundreds of people. So how does our Stone Age brain handle such large numbers when judging someone’s attractiveness? Today I report the findings of some of my own research published in The Journal of Sex Research.
The study
In 2017, Steve Stewart-Williams and I asked 188 participants from the U.K. to tell us how willing they would be to have a long-term relationship with someone based on their previous number of sexual partners. We started low: What if the person was a virgin? What about if they had just one previous partner? What about 19-22? What about more than 60? The participants rated 16 different histories in total, each time indicating their willingness on a nine-point scale from very willing to very unwilling.
The study format was basic, and intentionally so, as mate selection involves a holistic judgment across many different traits. Stripping these traits away allowed us to get a clearer idea of the influence of past partner numbers in the first instance.
Among others, our goals were to get an idea of how many sexual partners is considered “too many” and whether this pattern was similar for both sexes. Psychologists often assume that there’s a double standard, with high numbers of sexual partners being celebrated in men and shunned in women.
How many is too many?
When we plotted the data, two things jumped out at us. First, we found a curve. There was a “peak” in willingness. People were typically less willing to consider a relationship with a virgin than someone with a bit of experience. But, after two to three partners, willingness declined steadily from about 7 out of 9 for four partners, to about 2 out of 9 for 60-plus.
Second, we found considerable overlap between the responses of men and women. Men were slightly more forgiving of a large sexual history than women, but this effect was small and tracked the same “pattern” as women. In short, there was very little evidence for a “double standard."
The costs of high numbers of partners
Why do we even see a drop? Why should humans care about their partner’s sexual history at all? Even in the restricted "Stone Age” mating market, having sex with someone who had a greater number of sexual partners than average had risks associated with it, the most obvious being sexually transmitted diseases, which would have greater reproductive consequences for ancestral men than women.
A colourful history might also have indicated that a prospective partner was less willing (or able) to commit to a relationship, with potential consequences for those looking to invest a lot of time and energy in a long-term committed relationship.
Thus, it makes sense that our ancestors paid attention to sexual history, even when dealing with relatively low numbers. And while the option to go back in time and ask them doesn’t exist, we are able to see evidence throughout history that their descendants did: Many cultures have practices and traditions related to sexual history, particularly when it comes to chastity.
A bit of a past but not too much
A surprising result of the study was the “peak.” Those with zero sexual partners were less attractive than those with two or three. People weren’t unwilling to get involved with a virgin, just less so. The willingness to date a virgin was just above 6 out of 9, a similar value to those with seven to eight past partners.
Why the reluctance for very low numbers? In the U.K., where it’s not generally expected that long-term partners will be virgins, having no sexual history might act signal that a prospective partner is unattractive in the eyes of others or that they lack the ability to attract others and get relationships off the ground. Both could have implications for relationship satisfaction.
The bottom line
Modern humans still seem to have Stone-Aged preferences when it comes to mate numbers. The ideal numbers are fairly low, certainly low enough to put them in the range that might be experienced by our ancestors. This is despite the fact that access to sexual partners is much easier in modern societies, and the risks of having them mitigated by health care and contraception.
That being said, culture may well have some impact on this pattern. For example, we might find that the decrease in willingness that accompanies greater numbers of partners is more of a gentle slope in socially liberal countries and a steeper one in conservative ones.
I found a similar pattern with mate preferences when comparing Eastern and Western countries—culture led to some relative differences in mate preferences but the overall pattern was quite similar.
What if you have a bit of a past, or maybe none at all? Should you be worried about your mating prospects? Perhaps, but I wouldn’t worry too much. As I mentioned earlier, this study excluded many of the rich cues we use when choosing mates. Sexual history might be important to some, but it might be trumped by other, more important, traits. More research is needed, but I suspect an “undesirable” sexual history might matter less than being a kind, intelligent, and ambitious suitor.