Venous thromboembolism (VTE) has a multifactorial pathogenesis involving genetic predisposition, acquired diseases and conditions, and lifestyle and environmental factors. Although the level of risk of VTE associated with air travel has been exaggerated through sensationalized reporting in the mass media, it has nevertheless been established now that long-haul flights represent a risk factor for deep vein thrombosis and pulmonary embolism, including fatal events. Potentially effective measures to reduce the risk of travel-related VTE include enhanced mobility, use of graduated compression hosiery and pharmacological interventions. Low molecular weight heparin (LMWH) is effective in reducing the incidence of VTE post-operatively (by 50-60%) as well as in hospitalized subjects more generally, with little increased risk of bleeding. Based on the low absolute risk of travel-related VTE in the overwhelming majority of women during early pregnancy, pharmacological thromboprophylaxis with LMWH can be justified.