Objective: To determine the prevalence of markers of thrombophilia in patients with severe form of ovarian hyperstimulation syndrome Design: Retrospective case – control study Setting: Unica, Institute for Reproductive Medicine, Brno Methods: Blood samples to test for markers of thrombophilia were obtained from 30 patients who were hospitalised for severe OHSS. Results were compared with two control groups. Results: None of the patients with severe OHSS had antithrombin, protein C or protein S deficiencies. We also did not observe increased prothrombin level. Six patients had factor V Leiden mutation (heterozygotes) which is statistically significant compared to control group (p = 0.01, OR 4.65) and 12 patients had mutation of MTHFR 677 (heterozygotes). None had prothrombin G20210A mutation. Conclusion: We found a statistically significant increase in the prevalence of factor V Leiden mutation (heterozygot) in Czech infertile women with severe OHSS. These findings suggest the increased risk of development of OHSS in these patients.

        Key words: ovarian hyperstimulation syndrome, thrombophilia, factor V Leiden mutation