Developmental Change in the Effects of Sexual Partner and Relationship Characteristics on Sexual Risk Behavior in Young Men Who Have Sex with Men.

Young men who have sex with men are substantially impacted by HIV/AIDS, and most new infections occur in serious romantic dyads. Young people experience substantial psychosocial and neurocognitive change between adolescence and emerging adulthood which impacts engagement in risk behaviors. We aimed to examine developmental change in the association between sexual partnership characteristics and condomless anal intercourse (CAI). Data were taken from an analytic sample of 114 young adult MSM from a longitudinal study of lesbian, gay, bisexual and transgender youth with 4-year follow-up. Rates of CAI were approximately 12 times higher in serious compared to casual partnerships, but this effect diminished in size over time. Partner age differences and violence were associated with more CAI, and these associations strengthened across development. Characteristics of serious relationships (e.g., power dynamics) were also examined. We discuss the need for HIV prevention strategies that address dyadic influences on CAI during this critical developmental period.