If someone cheats on their partner in one relationship, what
are the odds they will do so in another relationship? That’s the question
addressed in a new study published in the Archives of
Sexual Behavior[i],
titled “Once a Cheater, Always a Cheater? Serial Infidelity Across Subsequent
Relationships.” The researchers found that those who were unfaithful in one
relationship had three times the odds of being unfaithful in the next, compared
to those who had not been unfaithful in the first relationship. Let’s look
deeper.
This research was conducted by a team from our lab at the
University of Denver; the study was headed up by Kayla Knopp along with colleagues
Shelby Scott, Lane Ritchie, Galena Rhoades, Howard Markman, and yours truly. It
used our national sample of individuals first recruited when aged 18 to 34, who
were in unmarried, serious, romantic relationships.[ii]
Thus, while most of the literature on infidelity focuses on marriage, this new
study focused on those mostly at pre-marriage stages of life. That is one of
the advances from this work but not the only one. The other is that the sample and
methods allowed for assessing infidelity across two relationships within the
context of this longitudinal sample that followed individuals for five years,
focusing on their romantic relationships.
Historical Findings
There is an extensive literature on infidelity in married
relationships with a growing literature on what is often called extra-dyadic
sexual involvement (ESI) in unmarried relationships. The literature on
infidelity inside and outside of marriage is well summarized in the new paper. I
will describe a few highlights here.[iii]
An overwhelming majority of people have the expectation of fidelity
of sexual and, often, emotional
connection in monogamous relationships. That is especially obvious in marriage,
but it’s also true in serious, unmarried relationships. Sure, there have always
been some who seek “open” relationships, where partners agree that it is okay
to have sex outside the relationship under some conditions, but that is not
very common.
While the lifetime risks for infidelity in marriage have
generally run around 20 percent,[iv]
rates of sex with someone outside a current relationship are much higher among
those who are unmarried.[v]
This should not be shocking since both the norms about fidelity as well as average
commitment levels are higher for marriage than other relationships, on average.
The possibility of fidelity is simply not as high for those who have not
settled down to make a long-term (or life-time) commitment to a particular
partner. Nevertheless, while people may not have settled down to committing to
another for the long haul, they tend to expect faithfulness.[vi]
Knopp and colleagues note some of the most common risk
factors for infidelity based on prior research. Those include:
·
Low commitment to the present relationship
·
Low or declining relationship satisfaction
·
Accepting attitudes about sexual relations
outside the relationship
·
Attachment insecurity: both avoidant and anxious
·
Differences in individual levels of sexual
inhibition and excitement
·
Being a man versus a woman, though this may be
changing.
Those findings are mostly from the literature on marriage
with some findings from unmarried relationships. If you want a deeper review of
factors associated with greater odds of cheating in unmarried relationships, I
wrote about that subject here
and here
based on an earlier study drawing from the same project sample as the new
study.
The new study does not focus on predictors of infidelity but
on the likelihood that it will be repeated, and it uses particularly strong
methods for doing so.
Following People
Through Two Relationships
Most studies of infidelity are retrospective and
cross-sectional, focusing at single points while asking about present and past
relationships.[vii] To
my knowledge, this new study is unique because people were followed in real
time (or close to it) from one relationship into the next, completing
comprehensive surveys about their relationships at each time point during the
longitudinal method. Contrast that with a method where, for example, you asked
a sample of middle-aged people if they had ever had sex outside of one or more relationships
in their past. That would be a different study, and, while interesting, would
be subject to retrospective bias. People are believed to remember things
better—and typically to report them more accurately—when asked closer in time
to when those events occurred. That’s what Knopp and colleagues did.
For the new study, the overall national sample from the project
started with 1,294 individuals. However, the analyses for this new study had to
be based on those who were surveyed across two
relationships over the course of the five years that the sample was followed. That
means that only those who had broken up from one relationship and then entered
another during that period would be analyzed. That left 484 individuals. If you
are used to studies in sociology with thousands of people, that may seem like a
smallish sample, but for the questions addressed here, it’s large and more than
sufficient.
The average duration of the first relationships was 38.8
months while the average duration of the second was 29.6 months. Thus, the
relationships studied were mostly serious and of substantial duration. No one
was married at the start of the project but some would have married that first
partner or the second during the time frame of the study. For the most part, however,
it is best to think about these findings in the context of the stage of life where
people are often seriously involved but not yet married—a stage of life that
has grown substantially in the past few decades.
At each time point (which tended to be every 4 to 6 months),
participants were asked, “Have you had sexual relations with someone other than
your partner since you began seriously dating?” In this project, participants
were also asked if they had either known or suspected their present partner of
having sex with someone else. Obviously, there are biases when people are
self-reporting such behavior. That’s a problem for the whole literature.
Further, the specific questions used in this study may exclude emotional
affairs as well as some online affairs where there is some sexual aspect but
the respondent tells themselves they are not actually having sex. Also, in such
a sample there would be some small percentage of people who would have been in
some sort of consensual non-monogamous arrangement, where having sex with
someone outside the relationship would be the same thing as cheating because
there was some agreement about this. Knopp and colleagues note that there is no
way with this data set to isolate such relationships, but there are strong
reasons to believe that such open relationships are a very small percentage in
the overall sample.
Knopp and colleagues controlled for some of the variables
known to be associated with greater and lower risk of being unfaithful, net of
other factors like relationship quality and commitment to one’s partner. That
is, the study controlled for age, gender, socioeconomic status, and race.
Then and Again
Forty-four percent (44 percent) of this sample reported
having had sex with someone other than their present partner in one or both of
the relationships studied. Further, 30 percent reported that they knew at least
one of the partners in the two relationships had cheated on them. That seems to
me like quite a bit of infidelity in these unmarried relationships. Nevertheless,
keep in mind that this is not a good estimate of the odds that someone will be
unfaithful in an unmarried relationship. To be in this sample, a person would
have had to have broken up in at least one serious relationship and entered
another. Thus, this result does not mean that 44 percent of those under 40 in
the U. S. have been unfaithful to a partner, and it certainly does not mean
that such a high percent who are married in a similar age range have or will be
been unfaithful. Getting that percentage measured correctly would require a
different type of sample and method to yield the best estimate of how likely it
is that people will have cheated on any partner before eventually settling down
in marriage among those who have married. Closely related to that question,
Galena Rhoades and I found in a previous study that 16 percent of those
followed into marriage in the study’s parent project described here reported
that they had cheated on their eventual spouse sometime before marriage.[viii]
In this new study, 45 percent who reported cheating on their
partner in the first relationship reported also doing so in the second. Among
those who had not cheated in the first, far less, 18 percent, cheated in the second.
While the odds of cheating on a partner were far greater if one had done so in
the past, it is also true that a person cheating in one relationship was not
destined to do so in the next relationship. In fact, slightly more people who had
cheated in the first relationship studied did not report cheating in the
second.
The study also found that those who were certain that their
partner in the first relationship had cheated were twice as likely as those not
reporting this to experience a cheating partner in the second relationship. Again,
history was not destiny, but history did speak to greater odds of a repeat
experience.
Implications
It would be incorrect to assume that one is destined to
endlessly repeat painful relationship patterns. And yet, some people are at much
greater risk than others for negative outcomes in romantic relationships (and
marriage), and they are at greater risk for repeat experiences. Some people are
simply more likely than others to cheat on their partners and more likely to
choose partners who cheat on them, and to do so in more than one relationship. This
touches on the complex subject of selection into risk, which Galena Rhoades and
I have written about more than a few times (for example, here
and here).
The study described here was not designed to address
complicated questions such as how the risk of infidelity might be lowered in
relationships and marriage, or how it could be prevented from happening again. Future
research could examine what predicts whether or not someone who cheated on one
partner does so again; however, most of the same predictors of ever cheating
will predict repeatedly cheating quite well. Among all of the factors
associated with cheating, some are surely more amenable to change than others.
Variables that are biological (e.g., differences in proneness to sexual
excitement) or cultural (and thus impacting individual values) are in the mix,
but so are other factors, like commitment, that I believe people have some
control over.
Galena Rhoades and I have
described how relationship histories may play an important and causal role
in eventual relationship quality in marriage (or not in marriage, for that
matter). Specifically, while having more
experience in various aspects of life is usually a good thing, having more experience
in relationships may not be so good when those experiences include serious
involvements that alter one’s odds of succeeding in finding and keeping lasting
love. Nevertheless, behaviors of the past do not have to be the definition of
one’s future.
This article was first posted at the blog for The Institute for Family Studies September 6th, 2017.
[i] Knopp,
K., Scott, S.B., Ritchie, L.L., Rhoades, G.K., Markman, H.J., & Stanley, S.M. (2017). Once a
cheater, always a cheater? Serial infidelity across subsequent relationships.
Archives of Sexual Behavior. Advance
online publication. https://doi.org/10.1007/s10508-017-1018-1
[ii]
The Relationship Development Study. For a description of the sample and basic
methods, see Rhoades, G. K., Stanley, S. M., & Markman, H. J. (2010). Should I stay or
should I go? Predicting dating relationship stability from four aspects of
commitment. Journal of Family Psychology, 24(5), 543-550.
[iii]
Since the literature is so well cited in the recent paper (and in papers cited
in the recent paper), I will make no attempt here to cite each point regarding
prior findings in this piece.
[iv] Allen,
E. S., Atkins, D., Baucom, D. H., Snyder, D., Gordon, K. C., & Glass, S. P.
(2005). Intrapersonal,
interpersonal, and contextual factors in engaging in and responding to
extramarital involvement. Clinical Psychology: Science and Practice, 12,
101-130.
[v] Treas,
J., & Giesen, D. (2000). Sexual
infidelity among married and cohabiting Americans. Journal of Marriage and
the Family, 62, 48–60.
[vi] Maddox
Shaw, A. M., Rhoades, G. K., Allen, E. S., Stanley, S. M., & Markman, H. J.
(2013). Predictors of
extradyadic sexual involvement in unmarried opposite-sex relationships.
Journal of Sex Research, 50(6), 598 - 610. DOI:10.1080/00224499.2012.666816
[vii]
There are also a few studies that look at what factors earlier in following a
longitudinal sample predict eventual infidelity, e.g.: Previti, D., & Amato, P.R. (2004). Is
infidelity a cause or a consequence of poor marital quality?
Journal of Social and Personal Relationships, 21,
217–230.; Allen, E. S., Rhoades, G. K., Stanley, S. M., Markman, H. J.,
Williams, T., Melton, J., & Clements, M. L. (2008). Premarital precursors of
marital infidelity. Family Process, 47, 243-259.
[viii]
Rhoades, G. K., & Stanley, S. M. (2014). Before
“I Do”: What do premarital experiences have to do with marital quality among
today’s young adults? Charlottesville, VA: National Marriage Project.
