LAUSR

OBJECTIVES To examine whether social aspects of the neighborhood environment are associated with early sexual initiation in a California agricultural community of predominantly Latinx adolescents. METHODS In a prospective cohort study of 599 eighth graders recruited from middle schools in Salinas, California (2015–2019), participants completed five interviews over 2 years. Social environment measures included neighborhood social dynamics (neighborhood disorder, social cohesion, and social network gang exposure); experiences of discrimination; and school connectedness. We estimated associations between baseline social environment and early sexual initiation (<15 years) using Poisson regression with robust standard errors. We compared contraceptive self-efficacy and attitudes by sexual initiation status using ANOVA. RESULTS Most youth were Latinx (94%) and age 13 (70%) at enrollment; 53% were female and 49% had a parent employed in agriculture. Additionally, 14% reported first vaginal sex before age 15. Neighborhood disorder (relative risk [RR], 1.13; 95% confidence interval [CI], 1.05–1.21), social network gang exposure (RR, 2.23; 95% CI, 1.49–3.33), and experiences of discrimination (RR, 1.67 [1–2 events versus none], 95% CI, 1.09–2.55; RR, 2.33 [3+ events versus none], 95% CI, 1.07–4.64) were associated with early sexual initiation. School connectedness was protective (RR, 0.44, 95% CI, 0.29–0.69). Youth who initiated sex before age 15 had more negative birth control attitudes and expressed lower motivation to use contraceptives. CONCLUSIONS Findings underscore opportunities to promote early adolescent sexual health through strengthening supportive and safe neighborhood environments with the promise of addressing disparities in unintended pregnancy and sexually transmitted infection rates in later adolescence.