Objective: Analysis of the issue of screening for Factor V Leiden mutation (FVL) in users of combined oral contraceptives (COC) or hormone replacement therapy (HRT). Design: Review article. Setting: Department of Obstetrics and Gynecology, Charles University and GeneralFaculty Hospital, Prague. Methods: Review of published facts, analysis of possibilities to screen all users or to test risk groups in the current situation in the Czech Republic. Conclusion: 1) Screening for FVL in allCOCorHRTusers is not recommended mostly for economical reasons. 2) Testing for FVL is indicated in women with a positive family history of thromboembolic disease and in obese women, if they consider COC or HRT despite our recommendation or in case there is a medical indication. 3) Deep venous thrombosis or pulmonary embolism are absolute contraindications of COC or HRT regardless of the presence of FVL.

        Key words: combined oral contraceptives, hormone replacement therapy, thromboembolic disease, Factor V Leiden mutation, hereditary thrombophilias