Adolescent Mental Health, Contraceptive Knowledge, and Teen Pregnancy Risk: A Systematic Review.

Background: Adolescent depressive and anxiety symptoms may erode motivation and problem-solving needed for timely contraception, while online information quality is uneven. We synthesized evidence linking mental health, contraceptive knowledge/access, and teen pregnancy risk. Methods: Following PRISMA-2020, we searched PubMed, Embase, and Scopus to 7 July 2025 for primary studies including adolescents that measured validated mental health symptoms or psychiatric settings and reported contraceptive knowledge/access/behavior and/or teen pregnancy outcomes. Two reviewers screened/extracted data; risk of bias was appraised with the Newcastle-Ottawa Scale and ROBINS-I. Given heterogeneity, we conducted narrative synthesis. Results: Six U.S.-based studies met the criteria, spanning community colleges, a national cohort, school surveillance, psychiatric inpatient care, and pediatric emergency departments (samples: n = 143 to weighted N = 29,755). Depressive symptoms were associated with contraception access (adjusted odds ratio [aOR] 1.58, 95% CI 1.27-1.96) and anxiety/stress with similar risk (aOR 1.46, 1.17-1.82). A first depressive episode in the same year as sexual debut increased teenage pregnancy hazard (adjusted hazard ratio 2.70, 1.15-6.34). School surveillance showed mental health indicators correlated with contraception non-use at last sex (odds ratios 1.78-2.71). Among psychiatric inpatients, not knowing where to obtain contraception and access difficulties strongly predicted interest in information (aOR 2.96-3.33) and initiation (aOR 2.85-4.72). In a pediatric emergency department trial, same-day initiation occurred in 26.8% versus 3.1% under usual care. Conclusions: Evidence directly linking adolescent mental health symptoms to teen pregnancy is limited (one study), whereas multiple studies show associations with contraception knowledge/access and delayed or non-use, suggesting plausible indirect pathways to pregnancy risk. These findings support hypothesis-generating, integrated approaches and highlight the need for studies with teen pregnancy endpoints.