Thromboembolism and thrombophilia in pregnancy

Venous thromboembolism (VTE) is one of the leading causes of maternal mortality worldwide and is also the cause of significant maternal morbidity. This article discusses the risk factors for VTE in pregnancy, the management of the pregnant woman at risk both antenatally and post-partum, and the acute management of VTE when it occurs during pregnancy.The thrombophilias, both heritable and acquired, are becoming increasingly recognised as a cause of morbidity and mortality both within and outside pregnancy. There has been a recent increased interest in the thrombophilias and their link with recurrent miscarriage, preeclampsia, abruption and intrauterine growth restriction. The relationship between the thrombophilias and adverse pregnancy outcome is addressed in detail, with reference to the current literature available on this evolving subject.     

Venous thromboembolism in pregnancy

Venous thromboembolism (VTE) includes deep vein thrombosis (DVT) and pulmonary embolism (PE). In pregnancy, deep vein thrombosis accounts for 75–80% of venous thromboembolism, the remainder are pulmonary embolisms. One half of these VTEs occur during pregnancy and the other half in the postpartum period. Venous thromboembolism is one of the leading causes of maternal mortality worldwide and is also the cause of significant maternal morbidity. This article discusses the risk factors for VTE in pregnancy, the management of the pregnant woman at risk both antenatally and postpartum and the acute management of VTE when it occurs during pregnancy.     

Thrombophilia and the risk for venous thromboembolism during pregnancy, delivery, and puerperium

The main inherited thrombophilias (antithrombin deficiency, protein C and S deficiency, FVL, the prothrombin gene variant, and MTHFR C677T homozygotes) have a combined prevalence in Western European populations of 15% to 20%. One or more of these inherited thrombophilias is usually found in approximately 50% of women who have a personal history of VTE. Obstetricians must therefore be aware of the interaction between thrombophilias and the procoagulant state of pregnancy and should have an understanding of additional risk factors that may act synergistically with thrombophilias to induce VTE. Such knowledge combined with the appropriate use of thromboprophylaxis and treatment in women who have objectively confirmed VTE continue to improve maternal and perinatal outcomes.     

Thromboembolic disease in pregnancy

Venous thromboembolic disease is a major cause of maternal morbidity and mortality. Virchow's triad of hypercoagulability, venous stasis, and vascular damage all occur during pregnancy. The risk of venous thromboembolism is five to six times higher during pregnancy and the puerperium. Risk factors include age greater than 35, antiphospholipid antibodies, inherited thrombophilias, operative delivery, increased parity, obesity, mechanical heart valves,and family history. Prophylactic and therapeutic anticoagulation is recommended for women at risk. Low molecular weight heparins are safe and effective in most cases.     

Thrombosis in Pregnancy: A Review

Venous thrombo-embolism (VTE) is the leading cause of maternal mortality. Thrombotic events are increased during pregnancy due to physiological changes in coagulation, venous stasis and pelvic vein injury. Symptoms of VTE can often be confused with normal pregnancy states. A high index of suspicion is essential to prevent serious morbidity and mortality following misdiagnosis. This article will outline the epidemiology, pathophysiology, investigations and treatment of VTE during pregnancy.     

Hemostatic problems before, during and after delivery.

Normal pregnancy and childbirth are known to be associated with marked changes in the coagulation and fibrinolytic systems. Generally, enhancement of clotting activity persists to prevent the risk of major hemorrhage. Hemostatic problems, either associated with a specific complication of pregnancy and labor or due to a hereditary or acquired bleeding diathesis or thrombophilias, present a significant cause of maternal and neonatal morbidity and mortality. This article reviews hemostatic disorders in pregnancy and the peripartal period from the standpoint of the obstetrician.     

Thrombophilia screening in pregnancy

Thromboembolism in pregnancy is a major contributor to pregnancy morbidity and mortality with potentially serious adverse effects for both mother and fetus. The purposes of this article are to explore the impact of heritable and acquired thrombophilias on pregnancy and to determine the appropriateness of screening for thrombophilias in pregnancy. In determining the appropriateness of screening, attention was given to the changes that occur in the coagulation and fibrinolytic systems during normal pregnancy. The impact of different heritable and acquired thrombophilias on maternal venous thromboembolism, fetal loss, and its impact on certain obstetric conditions are then explored. Guidelines and conclusions are made as to the appropriateness of screening. TARGET AUDIENCE: Obstetricians & Gynecologists, Family Physicians. LEARNING OBJECTIVES: After completion of this article, the reader should be able to list the various thrombophilias associate with pregnancy, to describe the impact of thrombophilias on pregnancy, and to outline the appropriate screening guidelines for thrombophilias during pregnancy.     

Venous thromboembolism as a cause of severe maternal morbidity and mortality in the United States

In the U.S., deaths due to pulmonary embolism (PE) account for 9.2% of all pregnancy-related deaths or approximately 1.5 deaths per 100,000 live births. Maternal deaths and maternal morbidity due to PE are more common among women who deliver by cesarean section. In the past decade, the clinical community has increasingly adopted venous thromboembolism (VTE) guidelines and thromboprophylaxis recommendations for pregnant women. Although deep vein thrombosis rates have decreased during this time-period, PE rates have remained relatively unchanged in pregnancy hospitalizations and as a cause of maternal mortality. Changes in the health profile of women who become pregnant, particularly due to maternal age and co-morbidities, needs more attention to better understand the impact of VTE risk during pregnancy and the postpartum period.     

Triage and management of the pregnant hypertensive patient

Hypertension during pregnancy is a leading cause of maternal and perinatal mortality and morbidity. Current thinking on the diagnosis and management of the hypertensive disorders of pregnancy is presented, along with triage and risk management issues.     

血栓性疾病史女性孕前系统管理

既往血栓性疾病史是妊娠女性发生静脉栓塞的首要高危因素,其造成的肺栓塞是危及孕妇生命的主要原因,同时血栓性疾病史孕妇也是子痫前期、死胎、胎盘早剥等不良妊娠并发症的高危人群。对这些人群进行系统孕前管理是减少或杜绝此类恶性事件发生的关键。     

Practice bulletin no. 124: inherited thrombophilias in pregnancy

Inherited thrombophilias are associated with an increased risk of venous thromboembolism and also have been linked to adverse outcomes in pregnancy. However, there is limited evidence to guide screening for and management of these conditions in pregnancy. The purpose of this document is to review common thrombophilias and their association with maternal venous thromboembolism risk and adverse pregnancy outcomes, indications for screening to detect these conditions, and management options in pregnancy.     

Anticoagulants

Pregnancy is a period of heightened coagulability and enhanced risk for thrombotic complications. Thromboembolism is the leading cause of maternal mortality. Anticoagulants are very useful during pregnancy for the acute treatment of venous thromboembolism and for the prevention of recurrent venous thromboembolism. They may also be beneficial in patients with thrombophilias, particularly among women who have experienced adverse pregnancy outcomes such as recurrent pregnancy loss. Anticoagulation is essential but problematic in the management of pregnant women with mechanical heart valve prostheses. When utilizing these medications among pregnant women the potential benefits must be balanced against the possibility of maternal haemorrhagic complications, adverse effects on the pregnancy or toxic effects on the fetus. This chapter summarizes current knowledge about the anticoagulant agents, their potential toxicities and their therapeutic role in pregnant women with various indications for anticoagulant therapy.     

Maternal venous thrombosis

Venous thrombosis remains a significant cause of maternal mortality and long-term morbidity, both in the developing and developed world. This review details the pathophysiology of venous thromboembolism in pregnancy and outlines the appropriate risk assessment, prophylaxis and management, which is required to minimise the burden of venous thrombosis on maternal health.     

妊娠相关静脉血栓栓塞症风险评估模型研究进展

妊娠相关静脉血栓栓塞症（pregnancy associated venous thromboembolism，PA-VTE）包括妊娠期和产褥期发生的静脉系统的血栓形成疾病，由深静脉血栓形成（deep vein thrombosis，DVT）和肺栓塞（pulmonary embolism，PE）组成的PA-VTE是发达国家孕产妇发病和死亡的主要原因。采用高效、便捷的风险评估模型评估PA-VTE的发病风险并进行分级预防是目前多个国家推荐的主要措施，但由于各国医学水平、经济发展和传统习惯的不同，各国相继开发风险评估模型或根据实际情况对其他国家的风险评估模型进行改良，进而对妊娠期及产褥期VTE风险进行个体化评估，并实施相应的血栓预防策略。通过回顾国内外的PA-VTE风险评估模型，旨在为我国进一步建立孕产妇的VTE防治指南提供依据，为产科医务工作者制定出适合我国产科人群的VTE风险评估模型提供参考。     

Acquired and inherited thrombophilia disorders in pregnancy

Thromboembolism is the leading cause of antepartum and postpartum maternal mortality. The presence of antiphospholipid antibodies is responsible for many pregnancy losses and other morbidities in pregnant women, and is the most prevalent and treatable cause of acquired thrombophilia in pregnancy. There is also evidence that women with thrombophilia are at increased risk not only of pregnancy-related venous thromboembolism but other vascular pregnancy complications. Many studies have examined the association between thrombophilia and pregnancy complications. This article reviews the most up-to-date knowledge of prevalence, pathogenesis, and diagnosis of acquired and inherited thrombophilias and their relationship and association with pregnancy complications.     

Drugs in pregnancy. Anticoagulants.

Pregnancy is a period of heightened coagulability and enhanced risk for thrombotic complications. Thromboembolism is the leading cause of maternal mortality. Anticoagulants are very useful during pregnancy for the acute treatment of venous thromboembolism and for the prevention of recurrent venous thromboembolism. They may also be beneficial in patients with thrombophilias, particularly among women who have experienced adverse pregnancy outcomes such as recurrent pregnancy loss. Anticoagulation is essential but problematic in the management of pregnant women with mechanical heart valve prostheses. When utilizing these medications among pregnant women the potential benefits must be balanced against the possibility of maternal haemorrhagic complications, adverse effects on the pregnancy or toxic effects on the fetus. This chapter summarizes current knowledge about the anticoagulant agents, their potential toxicities and their therapeutic role in pregnant women with various indications for anticoagulant therapy.     

The use of low-molecular-weight heparin for the management of venous thromboembolism in pregnancy

Thromboembolic disease is a rare, but important, complication of pregnancy that remains a leading non-obstetric cause of maternal death. The prevention and management of venous thromboembolism (VTE) in pregnant women is a complex area of medicine: a balance must be found between protecting the health of the mother and minimizing the risk to the unborn fetus. Until now, unfractionated heparin has been regarded as the drug of choice for the prevention and treatment of VTE during pregnancy. However, because of its significant side effects (osteoporosis and heparin-induced thrombocytopenia), the inconvenient mode of administration and need for monitoring, unfractionated heparin is now being replaced by low-molecular-weight heparin (LMWH). There is a convincing body of clinical evidence from well-designed studies and prospective case series that supports the efficacy and safety of LMWH in pregnant women. There are also encouraging observations on the efficacy of LMWH in the prevention of severe obstetric complications, which are frequently associated with inherited or acquired thrombophilias. The recently-published guidelines of The American College of Chest Physicians (ACCP), summarized in this review, allows the development of higher clinical standards. However, there is concern over the greater cost of LMWH compared with unfractionated heparin and oral anticoagulants, and cost-effectiveness studies are needed.     

妊娠期高血压疾病并发产后出血的防治

妊娠期高血压疾病是产科最常见的并发症,能引发全身重要脏器的病理改变,出现一系列并发症。产后出血仍然是威胁孕产妇生命的重要因素,妊娠期高血压疾病由于本身的病理生理特点,具备了发生产后出血的高危因素,尽早识别该类患者,并积极正确的处理能改善孕产妇预后,降低孕产妇病死率。     

Thromboembolism and thrombophilia

Thromboembolism remains the major cause of maternal mortality in the UK. There are important differences in the diagnosis and treatment of thrombosis in pregnancy compared with the non-pregnant patient. Thromboprophylaxis for high risk women (for example previous thrombosis) and for women in high risk obstetric situations (for example, Caesarean section) should be considered. Inherited and acquired thrombophilias increase the risk of thrombotic episodes during pregnancy, and may play a role in adverse obstetric events.     

Venous thromboembolism and pregnancy

Venous thromboembolism remains a major cause of maternal morbidity and mortality. Pregnancy is a thrombogenic state; therefore, clinicians must be familiar with the diagnosis and treatment of acute VTE. It is of paramount importance when caring for pregnant women to understand which patients are at risk for VTE and to use thromboprophylactic heparin accordingly.