Background <p>Teenage pregnancy remains a significant public health concern, especially in low- and middle-income countries. In India, limited data exist on adolescent girls’ knowledge and attitudes toward teenage pregnancy, particularly in the aftermath of the COVID-19 pandemic. This study aimed to assess the levels of knowledge and attitudes and identify key predictors influencing teenage pregnancy among adolescent schoolgirls in Theni District, Tamil Nadu.</p> Methods <p>A cross-sectional study was conducted among 548 adolescent girls aged 13–19&#xa0;years, using a multi-stage sampling method across selected schools in Theni district. A semi structured, pre-tested questionnaire assessed knowledge and attitudes regarding teenage pregnancy. Data were analyzed using descriptive statistics, chi-square tests, and multivariate ordinal logistic regression to identify significant predictors.</p> Results <p>Among the participants, 41.8% demonstrated moderate knowledge, 22.6% adequate knowledge, and 35.6% inadequate knowledge about teenage pregnancy. While 35.1% expressed unfavourable attitudes, 33.9% held neutral and 30.9% favourable views. Multivariate analysis revealed that age (OR 2.47), educational level (OR 3.27), parental occupation, and contextual factors such as fear of elopement (OR 3.06), cultural pressure (OR 2.54), financial instability (OR 1.57), and knowing adolescents married during COVID-19 (OR 0.55) significantly influenced knowledge levels. Familial factors such as parental alcohol use and conflict were also associated with both knowledge and attitudes.</p> Conclusion <p>The study highlights moderate knowledge and mixed attitudes among adolescents, shaped by socio-demographic, familial, and pandemic-related experiences. Interventions should integrate comprehensive sexuality education and family-centered approaches, while addressing socio-cultural and economic pressures to effectively reduce teenage pregnancy rates.</p>