Timing of Sexual Initiation in Polish Adolescents: A Multilevel Study of Individual, Family, and Contextual Determinants.

This cross-sectional study examined the timing and multilevel correlates of first sexual intercourse among 3,151 Polish adolescents (49.8% boys; mean age = 15.7 ± 1.6 years). Using Cox proportional hazards regression and structural equation modeling (SEM), gender-specific associations and pathways linking community, family, and individual factors to sexual debut were assessed. The median age at first sex was 17.49 years for boys and 18.08 years for girls. Cox regression identified key predictors of earlier sexual debut: for boys, higher peer popularity (HR = 1.44, 95% CI: 1.18-1.76), vigorous physical activity (HR = 3.36, 95% CI: 1.40-5.09), and alcohol use (HR = 2.95, 95% CI: 2.56-3.40); for girls, lower subjective well-being (HR = 1.69, 95% CI: 1.26-2.04), poorer self-rated health (HR = 1.69, 95% CI: 1.26-2.04), greater body dissatisfaction (HR = 1.66, 95% CI: 1.07-1.95), and substance use (HR = 2.40, 95% CI: 1.60-3.61). SEM showed that family and community factors had weak direct effects but acted indirectly through risky behaviors and, for girls, via subjective well-being, explaining 41.5% of the variance in boys and 36.3% in girls. Most associations operated additively, however, limited synergistic effects amplified the role of risky behaviors in less supportive contexts. Multi-group analysis revealed shared (behavioral) and different pathways to sexual debut: girls' well-being was more affected by family and community contexts; boys' risky behaviors were more strongly related to school type and urban residence. The findings highlight common and gender-specific mechanisms of sexual debut emphasizing the need for context-sensitive interventions to promote healthy sexual development.