Andrea Gerhardt

Prothrombin and factor V mutations in women with a history of thrombosis during pregnancy and the puerperium

Background Venous thromboembolism is a leading cause of morbidity and mortality during pregnancy and the puerperium. However, the role of mutations in the prothrombin and factor V genes and other thrombophilic abnormalities as risk factors for thromboembolism in women during pregnancy and the puerperium is not known. Methods In a study of 119 women with a history of venous thromboembolism during pregnancy and the puerperium and 233 age-matched normal women, we measured the activity of antithrombin, protein C, protein S, and lupus anticoagulant. We also performed genetic analyses to detect the G1691A mutation in the factor V gene (factor V Leiden), the G20210A mutation in the prothrombin gene, and the C677T mutation in the methylenetetrahydrofolate reductase gene. Blood samples were obtained at least three months post partum or after the cessation of lactation. Results Among the women with a history of venous thromboembolism, the prevalence of factor V Leiden was 43.7 percent, as compared with 7.7 percent ...

Fondaparinux is an effective alternative anticoagulant in pregnant women with high risk of venous thromboembolism and intolerance to low-molecular-weight heparins and heparinoids

Fondaparinux is an effective alternative anticoagulant in pregnant women with high risk of venous thromboembolism and intolerance to low-molecular-weight heparins and heparinoids -

Inherited thrombophilia and gestational venous thromboembolism.

Thromboembolic disease is a leading cause of maternal morbidity and mortality during pregnancy and the puerperium. To reduce the incidence of venous thromboembolism in pregnancy and improve outcomes, an individual risk stratification based on probability of thrombosis as a rationale for an individual risk-adapted prophylaxis is required. Within the past 10 years, a significant improvement in risk estimation has been achieved due to the identification of new genetic risk factors of thrombosis. In women without prior thrombosis, the presence of a heterozygous factor V Leiden or heterozygous G20210A mutation in the prothrombin gene is associated with a pregnancy-associated thrombotic risk of approximately 1 in 400. Thus, in pregnant carriers of either one of these mutations the risk of venous thromboembolism is low--indicating that pregnancy-associated thrombosis is multicausal, resulting from the interaction of combined defects. A combination of the two genetic risk factors can increase the risk to a modest level (risk 1 in 25). In women with a single episode of prior thrombosis associated with a transient risk factor, for example, surgery or trauma, and no additional genetic risk factor, the probability of a pregnancy-associated thrombosis appears also to be low. In contrast, in women with a prior idiopathic venous thrombosis who carry an additional hereditary risk factor or who have a positive family history of thrombosis, a high risk (>10%) can be expected, supporting the indication for active antepartum and postpartum heparin prophylaxis. Despite the remarkable progress in risk stratification, the absolute magnitude of risk in many cases is unknown and current recommendations remain empirical.

The polymorphism of platelet membrane integrin α2β1 (α2807TT) is associated with premature onset of fetal loss

Inherited thrombophilia could increase susceptibility to adverse pregnancy outcomes such as fetal loss. We determined the G1691A mutation of the factorV gene (FVL), the G20210A mutation of the prothrombin gene, the C677T polymorphism of the methylenetetrahydrofolate-reductase (MTHFR) gene, the HPA-1 polymorphism of the beta3 subunit of the platelet integrin alphaIIbbeta3 and the C807T polymorphism of the alpha2 subunit of integrin alpha2beta1 in 104 women with fetal loss and 277 normal women. In a subgroup analysis of women with recurrent early fetal loss (n=34), the prevalence of the genetic markers did not differ significantly between the women with early fetal loss and the normal women. However, in this subgroup of patients the onset of fetal loss was significantly earlier in women with the alpha2807TT genotype (7.1 +/- 1.9 vs. 8.8 +/- 1.5 weeks, p=0.001). No such significant difference was observed in carriers of the other genetic markers. In the subgroup analysis of women with late fetal loss (n=70), only the prevalence of heterozygous FVL was significantly associated with late fetal loss (odds ratio 3.2, p=0.002). There was no significant association of any genetic risk factor with premature fetal loss in the subgroup analysis of women with at least one late miscarriage. This study demonstrates a significant association of the alpha2807TT genotype of the platelet membrane integrin alpha2beta1 with premature onset of early fetal loss. It appears that this risk factor does not induce the pathomechanism, but modulates the course of fetal loss. Furthermore, our study confirms the association of FVL with late fetal loss.

Hereditary risk factors of thrombophilia and probability of venous thromboembolism during pregnancy and the puerperium

Venous thromboembolism (VTE) is a leading cause of maternal mortality. Few studies have evaluated the individual risk of gestational VTE associated with heritable thrombophilia, and current recommendations for antenatal thromboprophylaxis in women with severe thrombophilia such as homozygous factor V Leiden mutation (FVL) depend on a positive family history of VTE. To better stratify thromboprophylaxis in pregnancy, we aimed to estimate the individual probability (absolute risk) of gestational VTE associated with thrombophilia and to see whether these risk factors are independent of a family history of VTE in first-degree relatives. We studied 243 women with the first VTE during pregnancy and the puerperium and 243 age-matched normal women. Baseline incidence of VTE of 1:483 pregnancies in women ≥35 years and 1:741 deliveries in women <35 years was assumed, according to a recent population-based study. In women ≥35 years (<35 years), the individual probability of gestational VTE was as follows: 0.7% (0.5%) for heterozygous FVL; 3.4% (2.2%) for homozygous FVL; 0.6% (0.4%) for heterozygous prothrombin G20210A; 8.2% (5.5%) for compound heterozygotes for FVL and prothrombin G20210A; 9.0% (6.1%) for antithrombin deficiency; 1.1% (0.7%) for protein C deficiency; and 1.0% (0.7%) for protein S deficiency. These results were independent of a positive family history of VTE. We provide evidence that unselected women with these thrombophilias have an increased risk of gestational VTE independent of a positive family history of VTE. In contrast to current guidelines, these data suggest that women with high-risk thrombophilia should be considered for antenatal thromboprophylaxis regardless of family history of VTE.

Treatment of pregnancy-associated venous thromboembolism - position paper from the Working Group in Women's Health of the Society of Thrombosis and Haemostasis (GTH).

Venous thromboembolism (VTE) is a major cause of maternal morbidity during pregnancy and the postpartum period. However, because there is a lack of adequate study data, management strategies for pregnancy-associated VTE must be deduced from observational stu-dies and extrapolated from recommendations for non-pregnant patients. In this review, the members of the Working Group in Womens Health of the Society of Thrombosis and Haemostasis (GTH) have summarised the evidence that is currently available in the literature to provide a practical approach for treating pregnancy-associated VTE. Because heparins do not cross the placenta, weight-adjusted therapeutic-dose low molecular weight heparin (LMWH) is the anticoagulant treatment of choice in cases of acute VTE during pregnancy. No differences between once and twice daily LMWH dosing regimens have been reported, but twice daily dosing seems to be advisable, at least peripartally. It remains unclear whether determining dose adjustments according to factor Xa activities during pregnancy provides any benefit. Management of delivery deserves attention and mainly depends on the time interval between the diagnosis of VTE and the expected delivery date. In particular, if VTE manifests at term, delivery should be attended by an experienced multidisciplinary team. In lactating women, an overlapping switch from LMWH to warfarin is possible. Anticoagulation should be continued for at least 6 weeks postpartum or for a minimum period of 3 months. Although recommendations are provided for the treatment of pregnancy-associated VTE, there is an urgent need for well-designed prospective studies that compare different management strategies and define the optimal duration and intensity of anticoagulant treatment.

Successful Use of Danaparoid in Two Pregnant Women With Heart Valve Prosthesis and Heparin-Induced Thrombocytopenia Type II (HIT)

Anticoagulant therapy with heparin for the prevention of thromboembolism in pregnant women with prosthetic heart valves is associated with an increased risk to the mother and/or the fetus. A life-threatening complication of the therapy with heparin is heparin-induced thrombocytopenia type II (HIT). danaparoid has not yet been reported to be safe and effective for this indication. This study reports on a 26-year-old woman with tricuspidal valve prosthesis and a 37-year-old woman with a St. Jude Medical mitral valve prosthesis who were anticoagulated with danaparoid during pregnancy because of HIT. Anti-Xa levels were between 0.6 and 1.2 IU/mL during pregnancy with target levels of 1.0 IU/mL. Cesarean section was performed at anti-Xa levels of 0.3 and 0.7 IU/mL. One woman developed a placental hematoma at the 32nd week of gestation, which did not increase over the following week. Both patients delivered healthy boys. Heparin-induced thrombocytopenia in pregnant women with prosthetic heart valve can be successfully managed with danaparoid.

Clinical risk factors for deep venous thrombosis in pregnancy and the puerperium.

Abstract Thromboembolic events are among the leading causes of maternal mortality. Mutations in the genes for clotting factors are known, but anamnestic factors can be found in a proportion of women with deep venous thromboses (DVT) during pregnancy and the puerperium. We here describe the clinical factors and pregnancy outcomes of such a group of 70 women who were all operated on for DVT. Highest risk is conferred by a familial history of clotting disease and by known mutations of the clotting factors. This might be used to target a high risk group for preventive treatment.

Induction of tolerance after combined immunosuppression and -adsorption in two patients with acquired haemophilia after severe haemorrhages controlled by sequential administration of rFVIIa and FEIBA

Induction of tolerance after combined immunosuppression and -adsorption in two patients with acquired haemophilia after severe haemorrhages controlled by sequential administration of rFVIIa and FEIBA -

Venous thromboembolism during pregnancy is not associated with persistent elevated activated protein C (APC) sensitivity ratio based on the endogenous thrombin potential

Women who are using oral contraceptives can acquire APC resistance, measured by the effect of APC on the endogenous thrombin potential (ETP). The objective of our study was to examine whether persistentAPC resistance determined with an ETP-based normalized APC sensitivity ratio (nAPCsr) is a risk marker for venous thromboembolism in women with pregnancy-associated thromboembolism. We determined the activities of antithrombin, protein C, protein S, and performed a genetic analysis of factor V Leiden G1691A, prothrombin mutation G20210A, and methylenetetrahydrofolate reductase mutation (MTHFR C677T) in 65 women with venous thromboembolism during pregnancy or the puerperium and in 114 normal women. A significantly (p<0.05) higher nAPCsr was present in normal women using hormones, in younger women (<or=45 yrs), and in women with carrier status of factorV Leiden. In normal women without factor V Leiden a significant (p<0.05) negative correlation of nAPCsr with age (r=-0.39), antithrombin activity (r=-0.38), protein S activity (r=-0.26), and a significant positive correlation with hormone intake (r=0.36) was present. nAPCsr is influenced by several coagulation parameters, which are modified by the use of oral contraceptives. Consequently, a multivariate analysis of our data did not show a significant association of nAPCsr to venous thromboembolism, neither as a continuous variable (odds ratio 0.8, 95% CI 0.6-1.1, p=0.10) nor using a cutoff value (nAPCsr cut-off 3.1: odds ratio 1.2, 95% CI 0.3-5.3, p=0.77). Our study demonstrates that nAPCsr is not a risk marker for pregnancy-associated venous thromboembolism.