This study examined the effect of pubertal timing, parenting style, and peer behaviors on the trajectories of pornography use among adolescents. Data consisted of 1272 boys and 1210 girls, who completed at least three waves of pornography use questions from 7th to 12th grade (the year 2007 to 2012). Group-based trajectory modeling was applied to identify the trajectories of pornography use. Multinomial logistic regression and the Z-mediation method were conducted to examine the influences of pubertal timing, parenting style, and peer behaviors on the trajectories and the mediating effect. The results showed that early puberty was associated with earlier exposure to pornography and more frequent exposure later. Parental monitoring protected adolescents from pornography use, whereas psychological control increased the chance of more exposure. Peer pornography use mediated the relationship between adolescent pornography use, pubertal timing, and parental style. This mediating effect was stronger among boys versus girls. These findings provide insight into the mechanism of pubertal timing, parental style, and peer influence on the trajectory of pornography use in adolescence.
