However, a new study calls into question the dominance of monogamy and suggests that other relationships can be equally satisfying by examining relationship and sexual satisfaction across a range of relationship types.
"It is generally believed that monogamous relationships lead to greater satisfaction, intimacy, commitment, passion and trust than non-monogamous relationships," said the study's lead author Dr. Joel Anderson, associate professor and principal investigator at the Australian Center for Research on Sexuality, Health and Society (ARCSHS) at La Trobe University in Melbourne, Australia. “This pervasive belief – which we call the ‘monogamy superiority myth’ – is often reinforced by stereotypes and media narratives.
"Our findings challenge this long-held assumption outside academia, providing further evidence that people in consensually non-monogamous relationships experience similar levels of relationship and sex satisfaction to those in monogamous relationships."
Non-monogamous relationships include various types of consensual arrangements, such as open relationships (where a couple is romantically involved but not sexually exclusive) and polyamory (where several romantic relationships occur simultaneously).
To the researchers' knowledge, their study is the first meta-analysis of evidence comparing relationship and sexual satisfaction with "relationship orientation," that is, monogamous and non-monogamous relationships. Additionally, they explored subgroups in the data, comparing satisfaction between heterosexual and LGBTQ+ participants, different types of non-monogamous relationships, and different dimensions of satisfaction such as trust, intimacy, or commitment. The researchers analyzed data from 35 studies involving a total of 24,489 participants that were conducted between 2007 and 2024 in the United States, Canada, Australia, Portugal, Spain, Italy or multiple countries.
In terms of relationship satisfaction, the findings showed that, overall, there were no significant differences between non-monogamous and monogamous individuals. And the effects didn't differ significantly between heterosexual and LGBTQ+ people, or when comparing non-monogamous relationship types, such as open and polyamorous relationships. The few studies that have examined specific components of relationship satisfaction have found no significant differences between monogamous and nonmonogamous individuals in terms of commitment, intimacy, and passion.
The differences in sexual satisfaction between monogamous and non-monogamous couples were not significant overall, suggesting that non-monogamous people are just as satisfied with their sex lives as monogamous people. Like relationship satisfaction, sexual satisfaction did not differ by gender identity (heterosexual vs. LGBTQ+) or non-monogamous relationship type.
"Love and sexual satisfaction contribute significantly to our overall well-being," said Anderson. "These results challenge some common misconceptions about non-monogamy. Although our findings suggest comparable levels of satisfaction, people in non-monogamous relationships often face stigma, discrimination and barriers to accessing supportive health care and legal recognition."
The researchers proposed an explanation for their findings.
"We think these findings may be driven by what we consider to be the most common problem in relationships and certainly the most common factor in relationship breakdown - infidelity," Anderson said. "People in non-monogamous relationships often have an agreement with their partner that means infidelity is not a relevant factor in their relationship, whereas for people in monogamous relationships it is naturally a heartbreaking experience."
This study has limitations. That said, the use of self-reports may introduce bias, and the sample population was predominantly Western, meaning generalizability may be limited. Despite these limitations, Anderson said the study is important in highlighting the need for inclusivity.
"This study highlights the need for a more inclusive view of different relationship structures. Healthcare professionals, therapists and policymakers must acknowledge and support diverse relationship structures rather than viewing monogamy as the default or ideal state," Anderson said.
The study was published in the Journal of Sexuality Research.