[Increased fetal risk of primary venous thrombosis presenting at a young age].

Based on the hypothesis that the predisposition to thrombosis in women suffering from deep venous thrombosis at young age can disturb also the uteroplacental circulation, the authors retrospectively analyzed the fetal outcome of 333 pregnancies in 101 women with thromboembolic event before 40 years of age and compared it to the fetal outcome of 2943 pregnancies in 1000 randomly selected obstetrical patients without thrombosis. The relative risks of adverse fetal outcomes in thromboembolic women were as follows: 1.85 (95% C.I.: 1.35-2.55) for the spontaneous miscarriage, 3.9 (95% C.I.: 2.20-6.93) for the second-trimester miscarriage, 1.74 (95% C.I.: 1.15-2.64) for the low birth weight, 2.82 (95% C.I.: 1.28-6.30) for the perinatal loss and 7.17 (95% C.I.: 2.64-19.47) for the abruption of placentae. Data obtained suggest that women with deep venous thrombosis at young age should encounter a higher risk of the uteroplacental thrombosis which results in increasing fetal morbidity and mortality during the second and third trimesters of gestation.