Abstract：
BACKGROUND: Hereditary hypofibrinogenemia is a rare fibrinogen disorder characterised by decreased levels of fibrinogen. Pregnant women with hypofibrinogenemia are at risk of adverse obstetrical outcomes, depending on the fibrinogen level.
OBJECTIVE: We investigated how the physiological changes of hemostasis throughout the pregnancy impact the hemostatic balance in a woman with hereditary mild hypofibrinogenemia.
METHODS: Fibrin clot properties were analyzed by turbidimetry and scanning electron microscopy, clot weight and red blood cells retention were measured by whole clot contraction, and in vitro thrombin generation was assessed by calibrated automated thrombogram and ex vivo by TAT.
RESULTS: Throughout the pregnancy, the fibrinogen levels increased reaching normal values in the third trimester (activity 3.1 g/L, antigen 3.2 g/L). In parallel, the fibrin polymerisation increased, the fibrinolysis decreased, the fibrin clot network became denser with thicker fibrin fibers, and the fibrin clot weight and red blood cells retention increased, reaching control\'s value at the third trimester. Similarly, in vitro and ex vitro thrombin generation increased, reaching maximum values at the delivery.
CONCLUSIONS: In this case of hereditary mild hypofibrinogenemia we observed a physiological increase of fibrinogen and thrombin generation. Future studies should focus on moderate and severe hypofibrinogenemia, to assess fibrinogen variation and the overall impact of increased TG on the hemostasis balance.
OBJECTIVE: We investigated how the physiological changes of hemostasis throughout the pregnancy impact the hemostatic balance in a woman with hereditary mild hypofibrinogenemia.
METHODS: Fibrin clot properties were analyzed by turbidimetry and scanning electron microscopy, clot weight and red blood cells retention were measured by whole clot contraction, and in vitro thrombin generation was assessed by calibrated automated thrombogram and ex vivo by TAT.
RESULTS: Throughout the pregnancy, the fibrinogen levels increased reaching normal values in the third trimester (activity 3.1 g/L, antigen 3.2 g/L). In parallel, the fibrin polymerisation increased, the fibrinolysis decreased, the fibrin clot network became denser with thicker fibrin fibers, and the fibrin clot weight and red blood cells retention increased, reaching control\'s value at the third trimester. Similarly, in vitro and ex vitro thrombin generation increased, reaching maximum values at the delivery.
CONCLUSIONS: In this case of hereditary mild hypofibrinogenemia we observed a physiological increase of fibrinogen and thrombin generation. Future studies should focus on moderate and severe hypofibrinogenemia, to assess fibrinogen variation and the overall impact of increased TG on the hemostasis balance.
摘要：
背景：遗传性低纤维蛋白原血症是一种罕见的纤维蛋白原疾病，其特征是纤维蛋白原水平降低。低纤维蛋白原血症的孕妇有产科不良结局的风险，取决于纤维蛋白原水平。
目的：我们研究了妊娠期间止血的生理变化如何影响遗传性轻度低纤维蛋白原血症妇女的止血平衡。
方法：通过比浊法和扫描电子显微镜分析纤维蛋白凝块的性质，通过整个凝块收缩来测量凝块重量和红细胞保留，和体外凝血酶生成通过校准的自动血栓图和通过TAT离体评估。
结果：在整个怀孕期间，纤维蛋白原水平在妊娠晚期达到正常值（活性3.1g/L，抗原3.2g/L)。并行,纤维蛋白聚合增加，纤维蛋白溶解减少，纤维蛋白凝块网络变得更致密，纤维蛋白纤维更厚，纤维蛋白凝块重量和红细胞滞留增加，在妊娠晚期达到控制值。同样，体外和体外凝血酶生成增加，在交货时达到最大值。
结论：在这种遗传性轻度低纤维蛋白原血症的病例中，我们观察到纤维蛋白原和凝血酶生成的生理性增加。未来的研究应集中在中度和重度低纤维蛋白原血症，评估纤维蛋白原变化以及TG升高对止血平衡的总体影响。
目的：我们研究了妊娠期间止血的生理变化如何影响遗传性轻度低纤维蛋白原血症妇女的止血平衡。
方法：通过比浊法和扫描电子显微镜分析纤维蛋白凝块的性质，通过整个凝块收缩来测量凝块重量和红细胞保留，和体外凝血酶生成通过校准的自动血栓图和通过TAT离体评估。
结果：在整个怀孕期间，纤维蛋白原水平在妊娠晚期达到正常值（活性3.1g/L，抗原3.2g/L)。并行,纤维蛋白聚合增加，纤维蛋白溶解减少，纤维蛋白凝块网络变得更致密，纤维蛋白纤维更厚，纤维蛋白凝块重量和红细胞滞留增加，在妊娠晚期达到控制值。同样，体外和体外凝血酶生成增加，在交货时达到最大值。
结论：在这种遗传性轻度低纤维蛋白原血症的病例中，我们观察到纤维蛋白原和凝血酶生成的生理性增加。未来的研究应集中在中度和重度低纤维蛋白原血症，评估纤维蛋白原变化以及TG升高对止血平衡的总体影响。
