GENETIC SUSCEPTIBILITY TO PREGNANCY-RELATED VENOUS THROMBOEMBOLISM - ROLES OF FACTOR-V-LEIDEN, PROTHROMBIN G20210A, AND METHYLENETETRAHYDROFOLATE REDUCTASE C677T MUTATIONS

OBJECTIVE: This study's objective was to evaluate the association betw een venous thromboembolism during pregnancy and the postpartum period and the factor V Arg 506 Gin (factor V Leiden), the prothrombin G20210 A, and methylenetetrahydrofolate reductase C677T polymorphisms. STUDY DESIGN: In this case-control study 42 case patients and 213 control su bjects (parous age-matched women without history of thrombosis) were g enotyped for all the polymorphisms. Moreover, antiphospholipid antibod ies and protein C, protein S, and antithrombin III deficiencies were i nvestigated in each case. RESULTS: Ten case patients (23.8%) and 4 con trol subjects (1.9%; odds ratio 16.3, 95% confidence interval 4.8-54.9 ) carried the factor V Leiden mutation; 13 case patients (31.0%) and 9 control subjects (4.2%; odds ratio 10.2, 95% confidence interval 4.0- 25.9) were carriers of the prothrombin G20210A allele. Finally, 12 cas e patients (28.6%) and 34 control subjects (16.0%; odds ratio 2.1, 95% confidence interval 1.0-4.5) were homozygotes for methylenetetrahydro folate reductase C677T. Overall, mutations were found in 25 case patie nts (59.5%) and 47 control patients (22.2%; odds ratio 5.2, 95% confid ence interval 4.9-19.6). One patient carried the antithrombin III defi ciency and 1 the protein S deficiency, whereas 2 women had a primary a ntiphospholipid syndrome. CONCLUSIONS: The significant risk estimates of having a pregnancy-related venous thromboembolism in the presence o f the prothrombotic genetic risk factors analyzed suggest to screen fo r these mutations women with a personal history of thromboembolic even ts during pregnancy or the postpartum period.