Dating & Relationships

How Many People Have Ever Had A Consensually Non-Monogamous Relationship?

May 30, 2016 by Justin Lehmiller

Consensually non-monogamous (CNM) relationships feature an explicit agreement that allows partners to have multiple sexual and/or romantic relationships at the same time. This can take numerous forms, from swinging to polyamory to open relationships, with people negotiating the rules and limits to their own comfort level.

Many people believe that CNM relationships are rare and, further, that they are primarily practiced by gay men. But is this really the case?

A new study published in the Journal of Sex & Marital Therapy suggests that people’s beliefs don’t match up to the reality when it comes to consensual non-monogamy.

In this study, researchers looked at two nationally representative U.S. datasets of single adults that, together, included nearly 9,000 participants. These folks were asked whether they had ever previously had an “open sexual relationship,” defined as “an agreed-upon, sexually non-exclusive relationship.” Participants simply answered yes/no to this question.

In both samples, the number who said yes was strikingly similar: 21.9% vs. 21.2%. Thus, just over 1 in 5 adults said that they’d had a CNM relationship before.

In addition, in both samples, those who identified as men, as well as those who identified as non-heterosexual (specifically, gay, lesbian, or bisexual) were more likely to have had a CNM relationship at some point in their lives.

However, it’s important to note that the vast majority of participants who reported having had CNM relationships were heterosexual (78-80%).

In other words, although sexual minorities are more likely to have had a CNM relationship, they clearly aren’t the ones driving the high overall prevalence rate.

These results represent the best available data we have regarding the prevalence of CNM relationships because they come from a nationally representative dataset. By contrast, virtually all previous studies have used convenience samples.

That said, there are some important limitations to this study. For one thing, only single adults participated. More research is therefore needed that considers people with different relationship statuses.

In addition, this study asked people whether they’ve ever had a CNM relationship. As a result, it doesn’t shed light on how many people are currently in CNM relationships, or what those relationships might look like.

Limitations aside, these findings are important because they challenge some common beliefs about consensual non-monogamy. In particular, it appears that CNM relationships are quite common and, further, that most people who have these relationships are heterosexual.

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To learn more about this research, see: Haupert, M., Gesselman, A., Moors, A., Fisher, H., & Garcia, J. (2016). Prevalence of experiences with consensual non-monogamous relationships: Findings from two nationally representative samples of single Americans. Journal of Sex & Marital Therapy. DOI:10.1080/0092623X.2016.1178675

Image Credit: 123RF/Iakov Filimonov

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Written by
Dr. Justin Lehmiller
Founder & Owner of Sex and Psychology

Dr. Justin Lehmiller is a social psychologist and Research Fellow at The Kinsey Institute. He runs the Sex and Psychology blog and podcast and is author of the popular book Tell Me What You Want. Dr. Lehmiller is an award-winning educator, and a prolific researcher who has published more than 50 academic works.

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