A recent study examines who is most likely to have sex with someone else while they are in a serious but unmarried romantic relationship. I am going to summarize the key findings for you here and give you a reference and link below where you can read more if you wish.
This study on what researchers call “extradyadic sex” was headed up by Amanda Maddox Shaw who used to work in our lab at the University of Denver and who is now a graduate student the University of Rochester. (She’s brilliant, by the way.) The authors of this particular study included Amanda Shaw, Galena Rhoades, Elizabeth Allen, yours truly, and Howard Markman.
Okay, on to the study.
Unless you live under a rock, you’ve noticed that in most industrialized nations, people are marrying later and later and having increasingly significant, romantic relationships prior to marriage. People who are seriously involved with another tend to expect sexual faithfulness even though they are not married. But how many people have sex with someone else when already in a serious romantic relationship? And what are the characteristics of the people who do versus those who do not have sex with someone else?
In our lab, we have collected data over time on a large, national sample of younger adults who were romantically involved. We recruited this sample such that, at the first time point, the participants were aged 18 to 34 and in serious romantic relationships that had lasted at least two months. Recruiting was conducted by the use of phone survey methods (230,000 phone calls were made to recruit the sample of around 1300 people who met the criteria. You should have seen my cell phone bill that month.). Asking that people be in a serious relationship of two months or more yielded a sample of people who had been in their present relationship for an average of two years. So, what we are talking about here are people who are already involved in important, ongoing, serious relationships. We have followed this sample for five years, including through all the potential changes in their relationships.The sample matches census characteristics for this age amazingly well. It tilts toward a lower average income, however, given that we recruited unmarried people in this age range.
What our team did, headed up by Shaw, was examine who was most likely to have sex with someone outside of their relationship over a period of 1.5 years from the first time point in the study. I refer to this as “cheating” in the title of this post because that is what most of it would entail. However, we are not able to tease out the small number of people who would have agreed with their partners to be in open relationships where it would not be cheating but it would merely be extradyadic sex. But most of what we’re talking about here would be cheating in the sense that it’s having sex with someone else where that would not have been considered “okay” by the partner. And even in unmarried relationships and dating relationships that have turned more serious, people have high expectations for their partner not to step out on them.
Based on some earlier work by Elizabeth Allen, Galena Rhoades, and others on our team, Shaw looked at whether characteristics of the individual or of their relationships tended to tell us more about who was most likely to sex with someone other than their partner over time. In this sample, 14% reported having sex outside of their relationship during the 1.5 years from when they began participating in the long-term study. [Added clarification on 7-31-2013: People who had already had sex with someone other than their partner at the first time point were excluded from these analyses in order to make sure that the study was looking at what predicted future extradyadic sex over the course of the 1.5 years.]
What I will now list are the variables (in no particular order) that we found to be associated with having extradyadic sex over the period of time studied (1.5 yrs).
Individual variables associated with extradyadic sex
- Having more sexual partners prior to the present relationship
- Greater use of alcohol
- Having parents who never married
Individual variables NOT associated with extradyadic sex
- Gender (males were not more likely than females to cheat)
- Having children (with partner or from prior relationships)
- Parental divorce
Relationship variables associated with extradyadic sex
- Lower relationship satisfaction
- Lower levels of dedication (commitment) to the partner
- Higher levels of negative communication
- A history of physical aggression in the relationship
- Not having mutual plans for marriage
- Suspicion of partner having sex with other(s)
- Partner has had sex with another
Relationship variables NOT associated with extradyadic sex
- Frequency of sex in present relationship
- Satisfaction with sex in present relationship
- Living together
I want to discuss a few highlights here and in my next post. I will leave other interesting details to those who would like to read the journal article written by Amanda Shaw and our team.
There are not a lot of studies looking at unmarried but serious romantic relationships with regard to cheating. That makes this sample we have quite valuable for addressing questions like this. Loads of studies look at infidelity in marriage but few have looked at unmarried serious relationships like we do here. With the changing times, what happens in unmarried relationships is increasingly important to understand because these relationships have massive impacts on peoples’ lives. I am not saying this is a good trend, just that it’s reality. (For more on that point, see my post on “WhatHappens in Vegas Stays in Vegas, Right? Thoughts on Life Before Marriage,” which I plan to update soon. So, stay tuned for that.)
Here’s a highlight from this new study described above. While there are some individual characteristics that were associated with having extradyadic sex, there were many more individual characteristics that were not associated with sex with another. The big story is that the characteristics of the relationship—especially the quality of the relationship—says the most about who is likely to cheat over time. Those who were less satisfied in their relationships, less committed to their partner, and who had reported more negative patterns of communicating were the ones most likely to have sex with another. Contrary to what you might have guessed, sexual frequency and sexual satisfaction with the partner were not associated with cheating. Rather, the overall quality of the relationship, apart from sex, is what mattered most--for both men and women.
In addition to the quality of the relationship, I want to point out that suspecting one’s partner of cheating or knowing one’s partner has cheated in the past was strongly associated with the likelihood a person would have sex with someone other than their partner in the future. In other words, people who think or know that their partner has had sex with someone else are more likely, over time, to do the same. Some of that is just part of the relationships having lower commitment and some is doubtless revenge, but I'd bet more on low commitment being the big story there.
The headline is that overall relationship quality mattered most in explaining who, in unmarried romantic relationships, was most likely to step out on their partner. I will pick up on some of the (surprising) things that were not associated with sex with others in my next post.
Citation and Funding:
Citation: Maddox Shaw, A. M.M., Rhoades, G. K., Allen, E. S., Stanley, S. M., & Markman, H. J.(2013). Predictors of extradyadic sexualinvolvement in unmarried opposite-sex relationships. Journal of Sex Research, 50(6), 598 - 610.DOI:10.1080/00224499.2012.666816
The project described was supported by Award Number R01HD047564 from the Eunice Kennedy Shriver National Institute of Child Health & Human Development. The content is solely the responsibility of the authors and does not necessarily represent the official views of the Eunice Kennedy Shriver National Institute of Child Health & Human Development or the National Institutes of Health.