Very-high-dose progestogen therapy, including with medroxyprogesterone acetate, megestrol acetate, and cyproterone acetate, has been associated with activation of coagulation and a dose-dependent increased risk of VTE. In studies with high-dose cyproterone acetate specifically, the increase in VTE risk has ranged from 3- to 5-fold. The incidence of VTE in studies with very-high-dose progestogen therapy has been found to range from 2 to 8%. However, the relevant patient populations, namely aged individuals with cancer, are already predisposed to VTE, and this greatly amplifies the risk.