Prothrombotic gene mutations in women with recurrent abortions and intrauterine fetal death

Aim. The factor V Leiden mutation (FVL) and the G20210 prothrombin gene mutation (FII G20210A) are well-established risk factors for venous thromboembolism. In the recent years many scientific reports have suggested that these defects are associated with an increased risk of intrauterine fetal death. The aim of our study was to investigate the prevalence of these molecular defects in subjects with history of unexplained pregnancy loss. Methods. One-hundred and fifty women, 99 with history of unexplained recurrent pregnancy loss (between the 13 t h and the 20 t h week of gestation) and 51 with history of unexplained fetal death (pregnancy loss after the 20 t h week of gestation) were studied for hereditary thrombophilia. Physiologic coagulation inhibitors (antitrombin III, protein C, protein S) were in the normal range. Results. The prevalence of FVL and FII G20210A mutations was compared in patients with recurrent pregnancy loss and in a control group of 115 healthy women, without history of pregnancy loss (6.1% and 8.1% for FVL and FII G20210A respectively vs 2.6% for both mutations in the control group, P=0.36 for FVL and P=0.13 for FII G20210A). FVL and FII G20210A mutations were significantly more prevalent in women with fetal death (19.6%, P=0.001 for both mutations). Conclusion. Our data suggest that the screening for the FVL and FII G20210A mutations is useful in the setting of unexplained early and late pregnancy loss. Further studies are necessary in order to clarify the real impact of prothrombotic molecular defects on the pregnancy outcome and then to evaluate the appropriate therapeutic approach.