Masturbation Trajectories from Late Adolescence into Mid-Adulthood: A Population-Based Longitudinal Study.

Masturbation with its numerous health benefits is an integral aspect of most people's sexuality and is typically observed across all stages of life. However, longitudinal studies exploring the frequencies of masturbation across major life phases are lacking. We examined the development of masturbation frequencies from ages 19-50 via multilevel growth curve modeling with a longitudinal population-based sample of 2,562 individuals. For women, masturbation frequency gradually increased until they were in their early 30s, followed by a slight decline. In contrast, men's masturbation practices remained largely stable across the investigated age span. Masturbation trajectories did not change for either gender when controlling for the frequency of partnered sex. However, accounting for partnership status and the frequency of sexual fantasizing changed the trajectories for men, but not for women. Compared to those who became parents, individuals who remained childless presented a greater increase in masturbation frequency until approximately age 30, followed by a greater subsequent decline. Participants with nonheterosexual sexual identity masturbated more frequently than did strictly heterosexual individuals, across all ages. Masturbation trajectories did not differ significantly across religious affiliation and educational attainment. Collectively, these findings suggest the autonomous nature of masturbation as a sexual activity in relation to the frequency of partnered sex but also underscore the importance of individual life circumstances and one's sexuality in shaping its expression throughout adulthood. Future research should further investigate the dynamics among partnered sexual practices, sexual and relational problems, and masturbation.