OBJECTIVES: Identify treatment patterns and cost for the prophylaxis of venous thromboembolism (VTEp) in patients undergoing total hip o knee replacement (THR oTKR) from the public payer perspective in Mexico. In addition, this study assesses VTE incidence rate and adverse events commonly with prophylaxis treatment. METHODS: A retrospective cohort in four public hospitals was conducted, recruiting 650 patients undergoing THR or TKR from September 2011 to February 2012. Through medical records review, demographic, clinical and resource utilization data was gathered over hospitalization period and ambulatory monitoring follow-up for 3 months. Patients were categorized according to VTEp treatment, incidence of VTE (deep vein thrombosis (DVP) and pulmonary embolism (PE)), and associated adverse events (major or minor bleeds). Direct medical cost (lenght of hospital stay, and ambulatory care) associated with each therapy were calculated and expressed in US dollars (USD) at exchange rate of 13.72 Mexican pesos/USD (June 2012). Statistical differences were identified by Kuskal-Wallis test. RESULTS: A total of 650 patiens were included, with an average age of 66 +/- 11 years, 55% men. With TKR 57% and THR 43%, were 66.5 had one co-morbidity, being the most frequent systemic hypertension (51%). VTEp was given to 95.3% of patients. The prescribed drugs were: enoxoparin (86%), nadroparin (6.4%), unfractionated heparin (0.8%), rivaroxaban (6.3%), dabigatran (0.5%). DVP incidence resulted in 0.3%, major bleeds in 0.2%, and minor bleeds in 0.6%. Mean direct medical costs for each agent were: enoxoparin 4.450 USD (2.458-14.733); nadroparin 3.016 USD (2.792-3.639); unfractionated heparin 4.603 USD (3.675-5.312); rivaroxaban 4.427 USD (3.626-6.885); dabigatran 4.347 USD (4.166-4.468); and without VTEp 5.077 USD (2.801-13.235) (p<0.05). CONCLUSIONS: VTEp therapies are common and safe in mexican patients. Incidence of VTE is low, while higher costs were observed in patients with non-prophylaxis treatment.