Abstract
<title>Abstract</title> <p> <bold>Background:</bold> Anemia among young adults entering higher education in low- and middle-income countries is under-investigated, particularly with respect to the joint patterning of gender and ethnicity. Vietnam's diverse student population and routine mandatory entry health screening provide a unique opportunity to examine these disparities at a life-course transition point. <bold>Objective:</bold> To determine the prevalence of anemia among first-year university students in northern Vietnam and to identify sociodemographic factors associated with anemia, with particular attention to gender and ethnic disparities. <bold>Methods:</bold> We conducted a cross-sectional analysis of mandatory entry health screening data from 620 of 990 (62.6%) first-year students at a health sciences university in northern Vietnam, collected in December 2025. Anemia was defined using World Health Organization gender-specific hemoglobin thresholds. Adjusted associations were estimated using multivariable logistic regression, with modified Poisson regression as a sensitivity analysis. A composite gender × ethnicity variable was constructed to examine joint patterning. <bold>Results:</bold> Anemia prevalence was 15.48% (96/620; 95% confidence interval [CI], 12.84–18.56%); 77.1% of cases were mild and no severe cases were identified. Female students (adjusted odds ratio [aOR], 1.80; 95% CI, 1.06–3.06) and ethnic minority students (aOR, 1.83; 95% CI, 1.03–3.25) had independently higher odds of anemia. Prevalence ranged from 9.3% (Kinh males) to 28.3% (ethnic minority females); the latter group showed more than three-fold adjusted odds compared with Kinh males (aOR, 3.30; 95% CI, 1.50–7.28). Microcytic indices predominated among anemic students (56.3%) but normocytic anemia was also common (43.8%), indicating possible etiologic heterogeneity. <bold>Conclusions:</bold> Approximately one in six students entered university with anemia, and the burden was disproportionately concentrated among ethnic minority female students. Mandatory university entry screening may serve as a scalable platform for early detection, risk-stratified referral, and equity-oriented follow-up. </p>