Reasons for sex and relational outcomes in consensually nonmonogamous and monogamous relationships

Approximately 4% of individuals in North America participate in consensually nonmonogamous (CNM) relationships, wherein all partners have agreed to additional sexual and/or emotional partnerships. The CNM relationships are stigmatized and viewed as less stable and satisfying than monogamous relationships, a perception that persists despite research evidence. In our study, we assess the legitimacy of this negative perception by using a self-determination theory (SDT) framework to explore how sexual motivation impacts relational and sexual satisfaction among CNM and monogamous participants in romantic relationships. A total of 348 CNM (n = 142) and monogamous participants (n = 206) were recruited from Amazon’s Mechanical Turk (MTurk. (2016). www.mturk.com) to complete a cross-sectional survey. Participants reported on their sexual motivations during their most recent sexual event, their level of sexual need fulfillment, and measures of sexual and relational satisfaction with their current (primary) partner. The CNM and monogamous participants reported similar reasons for engaging in sex, though CNM participants were significantly more likely to have sex for personal intrinsic motives. No differences in mean levels of relationship and sexual satisfaction were found between CNM and monogamous individuals. Participants who engaged in sex for more self-determined reasons reported increased relational and sexual satisfaction. This relationship was mediated by sexual need fulfillment; participants who reported more self-determined motives reported higher levels of need fulfillment and, in turn, greater relationship and sexual satisfaction. This study indicates that CNM and monogamous individuals report similar levels of satisfaction within their relationship(s) and that the mechanisms that affect relational and sexual satisfaction are similar for both CNM and monogamous individuals. Our research extends theoretical understandings of motivation within romantic relationships and suggests that SDT is a useful framework for considering the impact of sexual motivation on relational outcomes.