Thrombophilia was present in 18.1% of the cases (230/1272), the most common presentation having antibodies associated with the antiphospholipid syndrome (59/212, 27.8%), prothrombin G20210A mutation (36/212, 17%), protein S deficiency (31/212, 14.6%), factor V Leiden mutation (25/212, 11.8%), antithrombin III deficiency (21/212, 9.9%), and protein C deficiency (15/212, 7.1%). This evidence concerns the gene PROS1 and antiphospholipid syndrome.