(253) Sexual Fluidity and Heteronormativity: A Mixed-Methods Investigation Project in the Portuguese Context

Introduction Heteronormativity can be understood as a dominant social system that positions heterosexuality as the default standard for relationships and identities, marginalizing those who do not conform to this framework. Therefore, sexuality is expected to adhere to a strict, binary model. In contrast, sexual fluidity refers to the potential for variability in sexual identity, romantic and sexual attraction, behaviors, and fantasies over time and in different contexts. Research on sexual fluidity remains limited, with few studies addressing all five dimensions of sexuality: sexual identity, romantic attraction, sexual attraction, sexual behavior, and sexual fantasy. Moreover, the relationship between sexual fluidity and heteronormativity is largely unexplored. However, some work has linked non-heteronormativity to experiences of sexual fluidity or examined its intersection with hegemonic masculinity among sexually diverse men. In Portugal, research is especially scarce, with only four studies addressing aspects of sexual fluidity. Objective This research aims to provide a comprehensive, multifaceted understanding of sexual fluidity and its intersection with heteronormativity in the Portuguese context. It aims to validate and adapt a measure of heteronormativity, document longitudinal changes in sexual trajectories, and explore lived experiences of sexual fluidity while examining how heteronormative norms shape these trajectories and experiences. Methods The project integrates cross-sectional, longitudinal, and qualitative methodologies across three studies. The first study will adapt and validate a scale in Portugal to measure heteronormative attitudes and beliefs. The second study will longitudinally track patterns of change in sexual trajectories and examine their relationship with heteronormative beliefs. This will occur over three data collection points, six months apart. A minimum of 100 adults, including heterosexual, cisgender individuals as well as those with diverse sexual and gender identities, will be recruited. The third study will consist of semi-structured interviews conducted with a subsample of participants from the longitudinal study who report experiences of sexual fluidity. Through thematic analysis, the study will explore personal narratives of sexual fluidity and the role of heteronormativity in shaping these experiences over time. Results The project is expected to yield several key outcomes. It will result in a validated Portuguese version of an instrument. It will identify and describe patterns and shifts in sexual fluidity over time, offering insights into how sexual fluidity manifests and also in relation to heteronormative beliefs. The qualitative component will provide rich, in-depth understandings of individual experiences and how social norms influence them. Overall, the findings should help clarify the complex interplay between identity processes and external normative structures. Conclusions This project aims to enhance comprehension of sexuality and foster the development of inclusive frameworks in education, health, and public policy that emphasize authenticity and acknowledge the fluid, dynamic, and complex nature of sexuality. The intersection with heteronormativity will allow us to contextualize the influence of social norms and understand reality beyond binary frameworks, promoting a broader view of sexual and gender diversity, with the aim of reducing discrimination and stigma in different contexts. Disclosure No