BACKGROUND: Association between estrogen receptor (ER) alpha polymorphism c.454-397 T>C and venous thromboembolism (VTE) has been reported in postmenopausal women. Comprehensive data are lacking. We herein evaluated the risk for VTE related to c.454-397 T>C ER alpha gene polymorphism in both men and women. PATIENTS/METHODS: The EDITH Study enrolled consecutive patients, aged over 18 years, hospitalized between May 2000 and December 2004 in Brest University Hospital with an objectively proven symptomatic VTE. For each case, one control who matched the case for age within a five-year age band, gender and major acquired risk factors, was selected. The present analysis was restricted to 677 cases with a VTE event not related to major acquired risk factors and their matched controls. RESULTS AND CONCLUSIONS: The relationship between VTE and c.454-397 T>C ER alpha polymorphism was consistent with a dominant model in women and a recessive model in men. Adjusted conditional odds ratios (95% CI) were 1.37 (1.05-1.78) and 1.29 (0.85-1.94) for CT/CC genotypes in women and CC genotype in men respectively compared to TT genotype. Among women hormone use did not substantially modify effect-measure estimate. Our results further extend results from previous studies. Other investigations are required to precise underlying mechanisms.