BackgroundIn Ethiopia, undernutrition among women on antiretroviral therapy has been a major challenge to achieve the full impact of intervention. Twenty seven percent and 17% of reproductive age Ethiopian women are chronically malnourished and anemic, respectively. Most studies to examine risk factors have been limited to the general population and ART-naive HIV-positive women, making it difficult to generalize findings to ART-treated HIV-positive women. The objectives of this study were thus to assess nutritional status and associated factors among adult women (≥20 years) on antiretroviral therapy.MethodsFrom August to September we conducted an Institution based cross-sectional survey among 276 women on antiretroviral therapy in Humera Hospital, Tigray, Ethiopia. Data was collected using structured and standard face to face interview, anthropometric measurements, BD FACS (CD4 count machine) and Sysmex-21 (hemoglobin analyzer). Logistic regression was done using SPSS version 16 to identify factors that are associated with nutritional status.ResultsThe prevalence of under nutrition (Body mass index < 18.5 kg/m2) Was 42.3% (95% CI: 37.4% - 47.3%). Severe, moderate and mild under nutrition was detected on 12%, 10% and 20.3% respondents, respectively. The prevalence of wasting (percentage body weight loss >5%) was 75% (95% CI: 70.4% - 79.2%). Severe wasting was accounted for 26.9% of respondents.In the multivariate analysis, Household food insecurity [AOR = 1.85; 95%CI 1.16, 2.86], inadequate dietary diversity [AOR = 1.19; 95%CI 1.08, 1.75], anemia [AOR = 1.67; 95%CI 1.05, 2.65] and absence of nutritional support [AOR = 0.34 95%CI 0.22, 0.54) were found to be independent predictors of under-nutrition.ConclusionHIV/AIDS is associated with an increased burden of undernutrition even among ART treated women in Humera Hospital, Tigray, Ethiopia. In addition to ART among HIV positive women interventions to ameliorate poor nutritional status may be necessary in this and similar settings. Such interventions aimed at improving household food security, dietary diversity, micronutrient supplementation, proper use of therapeutic food, as well as treating oral candidiasis.