The Safety of Low-Molecular-Weight Heparin During and After Pregnancy

How I diagnose and treat antiphospholipid syndrome in pregnancy

ABSTRACT

Antiphospholipid syndrome (APS) is a rare autoimmune disease characterized by arterial, venous, or microvascular thrombosis, pregnancy morbidities, or nonthrombotic manifestations in patients with persistently positive antiphospholipid antibodies. These antibodies bind cellular phospholipids and phospholipid-protein complexes resulting in cellular activation and inflammation that lead to the clinical features of APS. Our evolving understanding of APS has resulted in more specific classification criteria. Patients meeting these criteria should be treated during pregnancy according to current guidelines. Yet, despite treatment, those positive for lupus anticoagulant have at least a 30% likelihood of adverse pregnancy outcomes. Patients with recurrent early miscarriage or fetal death in the absence of preeclampsia or placental insufficiency may not meet current classification criteria for APS. Patients with only low titer anticardiolipin or anti-β(2)-glycoprotein I antibodies or immunoglobulin M isotype antibodies will not meet current classification criteria. In such cases, clinicians should implement management plans that balance potential risks and benefits, some of which involve emotional concerns surrounding the patient's reproductive future. Finally, APS may present in pregnancy or postpartum as a thrombotic microangiopathy, a life-threatening condition that may initially mimic preeclampsia with severe features but requires a very different treatment approach.

Low-molecular-weight heparin for the prevention of preeclampsia in high-risk pregnancies without thrombophilia: a systematic review and meta-analysis

OBJECTIVES

To systematically evaluate the efficacy of low molecular weight heparin (LMWH) to prevent preeclampsia in high risk pregnant women without thrombophilia.

SEARCH STRATEGY

PubMed, Embase and the Cochrane library were searched for articles published before 1st August 2022 using the combination keywords "preeclampsia", "Low Molecular Weight Heparin", "LMWH", "Heparin, Low Molecular Weight", "Dalteparin", "Nadroparin", and "Tinzaparin".

SELECTION CRITERIA

Randomized controlled trials evaluating the use of LMWH in pregnant women at high risk of preeclampsia without thrombophilia.

DATA COLLECTION AND ANALYSIS

Ten studies were included in the meta-analysis (1758 patients in total). Outcomes were expressed as relative risk (RR) with 95% confidence intervals (CI).

RESULTS

LMWH reduced the incidence of PE (RR = 0.67; 95% CI = 0.50-0.90; P = 0.009) in high risk pregnant women without thrombophilia. Subgroup analysis found that the prophylactic effect of LMWH was only significant in studies using low-dose aspirin (LDA) as the primary intervention. The combination of LMWH and LDA was also effective for the prevention of preterm birth and fetal growth restriction, but had no effect on the incidence of placenta abruption.

CONCLUSION

For women at high risk of developing preeclampsia without thrombophilia, the combination of LMWH and low-dose aspirin is effective for the prevention of preeclampsia, preterm birth and fetal growth restriction and is superior to LDA alone.

A comprehensive view of pregnancy in patients with sickle cell disease in high-income countries: the need for robust data and further decline in morbidity and mortality

Sickle cell disease is a major public health concern due to its prevalence and associated morbidities. In high-income countries, diagnosis and treatment advancements have extended patient's lives and enabled women to embrace motherhood. Although the provision of care in specialist centres has reduced maternal-fetal complication rates, the mortality rate among pregnant women with sickle cell disease remains disproportionately high. Complications arise from vaso-occlusive events, worsening organ damage, thrombotic risks, infections, and pregnancy-related issues, such as pre-eclampsia, premature birth, small-for-gestational-age, and pregnancy loss. Effective management during pregnancy includes preconception planning, genetic counselling, education, and collaborative care. There is no consensus on the overall approach to managing pregnant women with sickle cell disease; however, fostering a collaborative relationship between health-care professionals and researchers is crucial for advancing the understanding and management of this illness. The disparities in health-care outcomes associated with ethnicity and economic insecurity affect patients with sickle cell disease but have not been examined extensively. Hence, health-care personnel need sufficient training to address these issues alongside broader societal efforts to confront racism and discrimination. Comprehensive national and global action plans are required to address the multifaceted challenges of sickle cell disease.

Application of low molecular weight heparins in umbilical artery thrombosis: A case series and review of the literature

RATIONALE

Low molecular weight heparins are widely used in various thrombotic diseases and exert a preventive effect on thrombosis in high-risk patients. Umbilical artery thrombosis (UAT) is a rare occurrence that is difficult to detect during routine prenatal visits but can lead to adverse perinatal outcomes.

PATIENT CONCERNS

The aim of this study was to elucidate the therapeutic effect of low molecular weight heparins on UAT and to provide a new treatment option for the timing of delivery timing.

DIAGNOSES AND INTERVENTIONS

A retrospective study was conducted on cases involving thrombosis of the umbilical cord enrolled from July 2017 to July 2022. Data were acquired and analyzed from medical records and the final diagnosis was confirmed by histopathology. All included patients received LWMHs therapy after initial diagnosis of UAT.

OUTCOMES

The mean age of the 10 pregnant women recruited into this study was 27.9 ± 4.0 year-of-age; 1 (10%) was elderly. The gestational age at diagnosis was 29.9 ± 3.7 weeks, the gestational age at termination was 36.3 ± 2.5 weeks and the mean gestational age of extension was 6.4 ± 4.2 weeks. Low molecular weight heparin sodium was administered after umbilical artery embolism was detected on ultrasound. The LWMHs treatment received by the included patients in this study was subcutaneous injection. The specific usage varies due to the types of LWMHs. Of the 10 cases, 5 (50%) had fetal distress but all fetuses were born alive without neonatal asphyxia. With regards to delivery mode, 9 pregnancies were terminated by cesarean section.

LESSON

Early anticoagulant treatment with LWMHs may improve pregnancy outcomes. The timing and mode of termination of pregnancy should be determined according to the condition of the mother and the fetus along with the gestational age.

Pharmacology of Heparin and Related Drugs: An Update

Heparin has been used extensively as an antithrombotic and anticoagulant for close to 100 years. This anticoagulant activity is attributed mainly to the pentasaccharide sequence, which potentiates the inhibitory action of antithrombin, a major inhibitor of the coagulation cascade. More recently it has been elucidated that heparin exhibits anti-inflammatory effect via interference of the formation of neutrophil extracellular traps and this may also contribute to heparin's antithrombotic activity. This illustrates that heparin interacts with a broad range of biomolecules, exerting both anticoagulant and nonanticoagulant actions. Since our previous review, there has been an increased interest in these nonanticoagulant effects of heparin, with the beneficial role in patients infected with SARS2-coronavirus a highly topical example. This article provides an update on our previous review with more recent developments and observations made for these novel uses of heparin and an overview of the development status of heparin-based drugs. SIGNIFICANCE STATEMENT: This state-of-the-art review covers recent developments in the use of heparin and heparin-like materials as anticoagulant, now including immunothrombosis observations, and as nonanticoagulant including a role in the treatment of SARS-coronavirus and inflammatory conditions.

Analysis of a maternal health medicines pipeline database 2000-2021: New candidates for the prevention and treatment of fetal growth restriction

OBJECTIVE

The Accelerating Innovation for Mothers project established a new database of candidate medicines under development between 2000 and 2021 for five pregnancy-related conditions, including fetal growth restriction. The objective was to assess medicines for fetal growth restriction and their potential for clinical use globally.

DESIGN

Landscape analysis.

SETTING

Global (focus on low- and middle-income countries, LMICs).

SAMPLE

Drugs, dietary supplements and biologics under investigation for prevention or treatment of fetal growth restriction.

METHODS

A research pipeline database of medicines was created through searching AdisInsight, PubMed and various grant and clinical trial databases. Analysis of clinical and preclinical candidates were descriptive.

MAIN OUTCOMES MEASURES

Fetal growth restriction candidates in clinical development were identified and ranked as high, medium or low potential based on prespecified criteria, including efficacy, safety and accessibility.

RESULTS

Of the 444 unique candidates in the database across all five pregnancy-related conditions, 63 were for fetal growth restriction. Of these, 31 were in clinical development (phases I, II or III) and 32 were in preclinical development. Three candidates, aspirin, l-arginine and vitamin D, were ranked as having high potential as preventive agents. There were no high-potential candidates for treating fetal growth restriction, although five candidates were ranked as having medium potential: allylestrenol, dalteparin, omega-3 fatty acids, tadalafil, and United Nations International Multiple Micronutrient Antenatal Preparation (UNIMMAP).

CONCLUSIONS

l-Arginine, aspirin and vitamin D are promising, high-potential preventative agents for fetal growth restriction. Based on the medicines pipeline, new pharmacological agents for fetal growth restriction are unlikely to emerge in the near future.

Pregnancy and COVID-19

Evidence indicates that SARS-CoV-2 infection increases the likelihood of adverse pregnancy outcomes. Modifications in the circulatory, pulmonary, hormonal, and immunological pathways induced by pregnancy render pregnant women as a high-risk group. A growing body of research shows that SARS-CoV-2 infection during pregnancy is connected to a number of maternal complications, including pneumonia and intensive care unit (ICU) hospitalization. Miscarriages, stillbirth, preterm labor, as well as pre-eclampsia and intrauterine growth restriction are also among the most often documented fetal implications, particularly among expecting women who have significant COVID-19 symptoms, often affecting the timing and route of delivery. Thus, prevention of infection and pharmacological treatment options should aim to minimize the aforementioned risks and ameliorate maternal, obstetric and fetal/neonatal outcomes.

Cerebral venous sinus thrombosis in pregnancy and puerperium: A comprehensive review

Cerebral venous sinus thrombosis (CVST) is a distinct neurological emergency caused by occlusion, either partial or complete, of the dural venous sinus and/or the cerebral veins. It occurs more frequently in women during pregnancy and puerperium as compared to the general population. The clinical diagnosis is difficult in some cases due to its variable clinical presentation with numerous causes and risk factors. The diagnosis can be made at an early stage if clinical suspicion is high with the help of advanced neuroimaging techniques that were developed recently. Early therapeutic intervention using anticoagulants allows for preventing complications and improving outcomes. In this article, we review the topic of CVST in pregnancy and the postpartum period with an emphasis on its epidemiology, pathophysiology, clinical presentation, and treatment. We also elaborate on several practical points that are important to the treating team. This review will help obstetricians, neurologists, and emergency physicians diagnose affected pregnant women as early as possible to provide prompt treatment and avoid adverse outcomes.

Low Molecular Weight Heparins (LMWH) and Implications along Pregnancy: a Focus on the Placenta

Low molecular weight heparins (LMWH) have been largely studied for their use during pregnancy. The biology and the pharmacology of these molecules are well known and may be summarized in three main mechanisms of action: anti-coagulant, anti-inflammatory, and immunomodulant. The clinical implications of these drugs during pregnancy are mainly related to their action on the placenta, because of the presence of specific molecular and cellular targets, particularly at the trophoblast-endometrial interface. As well as for the prevention and treatment of thromboembolism, LMWH have been largely investigated for the improvement of embryo implantation and for the prevention of placenta-related complications such as preeclampsia, fetal growth restriction, and intrauterine fetal death. However, data on this topic are still unclear. The present review discusses the biological features, the mechanisms of action, and the possible contribution of LMWH to the success of placentation along pregnancy, pointing out the need for future basic science and clinical researches in this important field with the final aim to improve clinical practice in high-risk pregnancies.

Management of Valvular Disease During Pregnancy: Evolving Role of Percutaneous Treatment

Valvular heart disease (VHD) is encountered in approximately 1% of pregnancies, significantly increasing both maternal and foetal risk. Rheumatic VHD remains the most common form in non-Western countries, whereas congenital heart disease dominates in the Western world. The risk of complications varies according to the type and severity of the underlying VHD. Moreover, pregnancy is a hypercoagulable state associated with increased risk of thromboembolism. The authors review the main VHDs encountered during pregnancy, and suggest management strategies based on the 2018 European Society of Cardiology recommendations for the management of pregnant women with VHD, providing an overview of classical and new transcatheter structural therapeutic options with a special focus on radiation exposure and anticoagulation drug management.

Ischaemic heart disease and pregnancy

Although ischaemic heart disease is currently rarely encountered in pregnancy, occurring between 2.8 and 6.2 per 100 000 deliveries, it is becoming more common as women delay becoming pregnant until later life, when medical comorbidities are more common, and because of the higher prevalence of obesity in the pregnant population. In addition, chronic inflammatory diseases, which are more common in women, may contribute to greater rates of acute myocardial infarction (AMI). Pregnancy itself seems to be a risk factor for AMI, although the exact mechanisms are not clear. AMI in pregnancy should be investigated in the same manner as in the non-pregnant population, not allowing for delays, with investigations being conducted as they would outside of pregnancy. Maternal morbidity following AMI is high as a result of increased rates of heart failure, arrhythmia and cardiogenic shock. Delivery in women with history of AMI should be typically guided by obstetric indications not cardiac ones.