We previously conducted a primary survey of pregnant women with hereditary thrombophilia based on national surveillance in Japan, but did not examine their thrombosis-related characteristics. Antithrombin (AT) deficiency, protein C (PC) deficiency and protein S (PS) deficiency are the major types of hereditary thrombophilia in Japan. We examined their detailed information related to thrombosis, and evaluated peripartum outcomes in comparison with control data obtained from the Japan Society of Obstetrics and Gynecology. Definite or probable AT deficiency, PC deficiency and PS deficiency were observed in 80, 50, and 317 pregnancies, respectively, from 2014 to 2018 in Japan, with prevalence rates among total deliveries of 0.011%, 0.007%, 0.044%. The number of pregnancies with AT, PC and PS deficiency might have been as many as 27, 17 and 108 every year if complete answers had been provided. In the peripartum period of current pregnancies, 27.5% of women with AT deficiency, 28.0% with PC deficiency and 13.2% with PS deficiency developed thrombosis (p < 0.001 vs. control). Pregnant women with AT and PC deficiency were more susceptible to thrombosis than those with PS deficiency (P < 0.01). Of the thromboses, 92.3% occurred during pregnancy, 62.8% at less than 15 gestational weeks. The earliest onset of thrombosis was 5 gestational weeks. Prophylactic anticoagulation significantly prevented the onset of both antepartum and postpartum thrombosis (p < 0.0001). The rate of recurrent pregnancy loss in women with low PC or PS activities was significantly higher than in controls (p < 0.0001); however, it is unknown whether recurrent pregnancy loss is related to hereditary PS deficiency. There seem to have been few serious maternal or fetal/neonatal complications due to placental insufficiency related to a hypercoagulable state other than growth restriction. This survey revealed the thrombosis-related characteristics of pregnant women with hereditary thrombophilia in Japan. We suggest prophylactic anticoagulation to prevent maternal or fetal/neonatal complications.

中文翻译：

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日本抗凝血酶缺乏、蛋白C缺乏和蛋白S缺乏孕妇的血栓形成相关特征

 我们之前根据日本的国家监测对患有遗传性血栓形成倾向的孕妇进行了初步调查，但没有检查她们的血栓形成相关特征。抗凝血酶（AT）缺乏、蛋白C（PC）缺乏和蛋白S（PS）缺乏是日本遗传性血栓形成倾向的主要类型。我们检查了他们与血栓形成相关的详细信息，并与日本妇产科学会获得的对照数据进行比较，评估了围产期结局。 2014年至2018年，日本在80例、50例和317例妊娠中分别观察到明确或可能的AT缺乏症、PC缺乏症和PS缺乏症，总分娩的患病率分别为0.011%、0.007%、0.044%。如果提供完整的答案，每年患有 AT、PC 和 PS 缺乏症的妊娠人数可能高达 27、17 和 108。在当前妊娠的围产期，27.5% 的 AT 缺陷女性、28.0% 的 PC 缺陷女性和 13.2% 的 PS 缺陷女性出现血栓形成（与对照相比，p < 0.001）。 AT和PC缺乏的孕妇比PS缺乏的孕妇更容易发生血栓（P < 0.01）。血栓形成中，92.3%发生在妊娠期间，62.8%发生在妊娠15周以内。血栓形成最早发生在妊娠5周。预防性抗凝可显着预防产前和产后血栓形成的发生（p < 0.0001）。 PC 或 PS 活性较低的女性的复发性流产率显着高于对照组 (p < 0.0001)；然而，目前尚不清楚复发性流产是否与遗传性 PS 缺乏有关。除生长受限外，由于与高凝状态相关的胎盘功能不全，似乎很少有严重的孕产妇或胎儿/新生儿并发症。这项调查揭示了日本遗传性血栓形成倾向孕妇的血栓形成相关特征。我们建议预防性抗凝，以预防孕产妇或胎儿/新生儿并发症。