Key Social Norms Take-aways This study finds that favorable social norms—especially descriptive and injunctive norms around early marriage—are significantly associated with greater agency among adolescent girls in Ethiopia. While norms supporting girls’ education and nutrition showed mixed associations, those related to early marriage had the strongest positive correlation with agency. However, agency domains related to sexual and reproductive health—specifically beliefs about contraception use and the right to refuse sex—scored lowest, indicating persistent normative barriers in these areas. The study highlights that enhancing girls’ agency requires addressing community-level norms, particularly those embedded in gender roles and expectations around sexuality and marriage.

Objectives To examine the relationship between adolescent girls’ agency and social norms related to education, early marriage, and nutrition, and to inform strategies for improving the sexual and reproductive health of young adolescents in Ethiopia.

Methods A cross-sectional study was conducted in 2016 with 3,186 adolescent girls aged 13–17 years in four districts of West Hararghe, Ethiopia. A two-stage cluster sampling method was used to randomly select participants. Data were collected using structured, pre-tested questionnaires and analyzed using multivariable linear regression models, accounting for complex survey design. Agency was measured through a validated scale adapted from CARE’s WE-MEASR tool, while descriptive and injunctive social norms were measured for each thematic area.

Results Adolescent girls’ agency was significantly associated with favorable descriptive norms around education (β = .19), marriage (β = .13), and nutrition (β = .20), and with injunctive norms around marriage (β = .21). However, injunctive norms around education and nutrition were not significantly associated with agency. The lowest scores within the agency scale were observed in domains related to contraception use and the right to refuse sex. Social and demographic variables such as age, education level, and father’s education were also positively associated with agency.

Conclusions To improve adolescent girls’ sexual and reproductive health outcomes, interventions must address social norms—particularly those concerning early marriage. While improving individual-level agency is important, social norm-shifting strategies that foster community support for girls’ autonomy, especially in areas related to sexual health and rights, are essential for lasting impact.