OBJECTIVES: Anemia affects about 25% of the world population and is the second main cause of incapacity worldwide. Clinical guidelines recommend upfront use of iron (oral or intravenous, IV) to correct iron deficiency anemia (IDA) instead of blood transfusion (BT). Nonetheless, utilization of BT is a common practice frequently associated with clinical complications and high economic burden. Our main objective was to estimate the impact of BT in hospital length of stay (LOS) and in intra- and extra-hospital mortality of patients with IDA. METHODS: This was a non-interventional, retrospective, single-center study. A convenience sample composed of 196 IDA patients treated with IV iron during 2013 was analyzed. Data was retrieved from patients’ clinical and pharmacy records. Between-group comparisons were performed using non-parametric methods (Mann-Whitney-Wilcoxon and Kruskal Wallis). Logistic regression models were estimated to assess the odds of intra-hospital mortality. Kaplan-Meier survival estimates and Peto test were used to assess survival after hospital discharge (extra-hospital mortality). A 5% significance level was adopted. RESULTS: Here we present the results of the subset of 136 hospitalized patients, mean (SD) age of 68.6 (18.7) years and 50.7% males, corresponding to 148 hospitalization episodes. In 62.2% of these episodes at least 1BT was performed. Mean LOS was significantly higher in patients with BT (29.2 versus 15.3 days; p-value<0.0001). The odds ratio of dying during hospitalization in patients with >2BT was 3.73 (95%CI: 1.01-13.74) when compared to patients with ≤2BT, adjusting for age, sex, surgery or iron IV utilization. We observed a higher extra-hospital mortality in BT patients although not statistically significant (p-value=0.118), probably due to the low number of patients with follow-up data (n=33). CONCLUSIONS: Blood transfusions result in higher hospital length of stay and mortality. A better patient blood-management may improve patient outcomes and provide a more efficient use of health resources.