Association of inherited thrombophilia with embryonic and postembryonic recurrent pregnancy loss.

To investigate the impact of maternal-inherited thrombophilia: effects of factor V Leiden (FVL) and prothrombin gene mutation (FII 20210G>A) on the development of recurrent pregnancy loss in embryonic and postembryonic periods. A total of 153 patients were analysed for FVL and FII 20210G>A according to placenta gestation: 94 women with embryonic loss prior 10 weeks of gestation and 59 women with postembryonic (early fetal) loss occurring between 10 and 14 weeks of gestation. The control group consisted of 100 healthy women, with at least one uncomplicated full-term pregnancy. FVL prevalence was not significantly associated with pregnancy loss prior to 10 weeks of gestation (9.6%) compared with controls (7%) [odds ratio (OR) 1.41; 95% confidence interval (CI) 0.454-4.416, P > 0.05], but it was much more pronounced in women with postembryonic loss (10-14 weeks of gestation) - 18.6% (OR 3.05; 95% CI 1.010-9.387, P = 0.047). FII 20210G>A was significantly higher in both groups with embryonic (17%) and early fetal losses (16.9%) as compared to controls (3%) (OR 6.63; 95% CI 1.731-29.752, P = 0.003; OR 6.60; 95% CI 1.572-31.856, P = 0.006). FII 20210G>A is significantly associated with an increased risk of early recurrent pregnancy loss throughout the entire first trimester. FVL was significantly higher only in early fetal period after starting of the placentation process, but not associated with embryonic recurrent pregnancy loss. These results suggested that the first trimester should be viewed rather as a heterogeneous interval, with different relation to FVL in the embryonic and postembryonic fetal period. Genetic testing should be applied according to the diverse contribution of thrombophilic markers to embryonic and postembryonic period.