<![CDATA[Sexually transmitted infections (STIs) among adolescents remain a serious yet frequently undetected reproductive health threat, compounded by social stigma and limited knowledge; confirmed STI cases among adolescents aged 15-24 years in Pati Regency rose by 18.3% in 2024, with the true burden presumed far higher (iceberg phenomenon), while the pathway linking Social Cognitive Theory (SCT) constructs to preventive knowledge remains poorly understood. This study aimed to analyze the adolescent reproductive health profile and STI occurrence in Pati Regency using SCT as an analytical framework. An explanatory sequential mixed-methods design was conducted across three sub-districts of Pati Regency from January to March 2026, involving 150 adolescents aged 15-24 years selected through stratified random sampling. Data were collected using validated structured questionnaires and clinical/laboratory STI examinations, then analyzed using chi-square, correlation, logistic regression, and SEM-PLS. Results showed an STI prevalence of 24.7%, with chlamydia as the most common type (43.2%); SEM-PLS revealed that attention strongly influenced retention (β=0.612; p<0.001), and motivation significantly predicted preventive-knowledge improvement (β=0.769; R²=0.591). Low STI knowledge (OR = 4.12; 95% CI: 2.18-7.79) and risky sexual behavior (OR = 4.89; 95% CI: 2.47-9.68) were significantly associated with STI occurrence (p < 0.000). These findings suggest that the sequential SCT constructs are associated with adolescents' STI preventive knowledge, consistent with the hypothesized SCT-based pathway, and point to the potential value of SCT-informed education in strengthening adolescent reproductive health practice and policy. Further research with longitudinal designs and larger, more diverse samples is needed to confirm and extend these findings.]]>
