Factor V Leiden and prothrombin G20210A polymorphisms as risk factors for miscarriage during a first intended pregnancy: the matched case-control 'NOHA first' study

Immunological Risk Factors in Recurrent Pregnancy Loss in Patients With Hereditary Thrombophilia

BACKGROUND

Recurrent pregnancy loss (RPL) is a complicated reproductive disorder with underlying genetic and immunological causes. RPL may be influenced by hereditary thrombophilia, a class of blood clotting-related genetic abnormalities, via the vascular and immune systems. This study examines the immunological characteristics that hereditary thrombophilia patients have in common with RPL.

METHODS

A prospective cohort study included 300 patients split into two groups: a control group without hereditary thrombophilia and a group with the condition. Interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), and interferon-gamma (IFN-γ) levels were measured, along with demographic specifics, antiphospholipid antibodies, natural killer (NK) cell counts, and other cytokines. Group differences were found using statistical analysis.

RESULTS

Antiphospholipid antibodies were significantly more common in the thrombophilia group (42% testing positive, p=0.001) compared to the control group (12% testing positive), despite demographic factors being similar between groups (p=0.372 and p=0.093). When body mass index (BMI) was taken into account, the study found a statistically significant difference (p=0.046), with the thrombophilia group having a higher mean BMI (26.3 kg/m2, standard deviation (SD): 2.8) than the control group (24.7 kg/m2, SD: 3.1). IL-6 (14.8 pg/mL, SD: 3.2, p=0.029) were higher than the control group (12.4 pg/mL, SD: 2.1), and TNF-α levels were higher in the thrombophilia group (10.5 pg/mL, SD: 2.0, p=0.012) compared to the control group (8.9 pg/mL, SD: 1.5), but NK cell counts did not differ significantly (p=0.213).

CONCLUSION

This study emphasizes the role of elevated pro-inflammatory cytokines (IL-6 and TNF-α) and antiphospholipid antibodies in RPL among people with hereditary thrombophilia. In this population, early detection and immunomodulatory interventions may improve pregnancy outcomes. To fully comprehend these mechanisms and create customized treatments, collaborative research is required.

The Diagnostics and Treatment of Recurrent Pregnancy Loss

Recurrent pregnancy loss is a common problem in the reproductive age population of women. It can be caused by many different conditions. This problem is addressed in international guidelines that take a slightly different approach to its diagnosis and treatment. The guidelines used in this review mainly use the guidelines of the Royal College of Obstetricians and Gynaecologists (RCOG), American Society of Reproductive Medicine (ASRM) and European Society of Human Reproduction and Embryology (ESHRE). This review shows how much the approach to miscarriages has changed and how much more needs to be explored and refined. The review also addresses the topic of unexplained pregnancy loss, which continues to be a challenge for clinicians.

Pathophysiological, immunogenetic, anatomopathological profile of thrombophilia in pregnancy

Thrombophilic states have been associated with early and/or late pregnancy loss and possibly other severe obstetrical complications. Pregnancy-induced hypercoagulability, increased stasis, and the consequences of inherited and acquired thrombophilia are just a few of the factors that contribute to the development of thrombosis in pregnancy. In this review, we illustrate the impact that these factors have on the development of thrombophilia during pregnancy. We also explore how thrombophilia impact pregnancy outcomes. Next, we discuss how human leukocyte antigen G plays a part in thrombophilia during pregnancy by regulating cytokine release to prevent trophoblastic cell invasion and maintain local immunotolerance constant. Human leukocyte antigen class E is briefly explored with thrombophilia in pregnancy. Regarding the anatomopathologic aspect, we describe the different histopathological lesions of the placenta found in women with thrombophilia.

Thrombophilia and Pregnancy

Leading cause of death in pregnant women still remains venous thromboembolism, with an incidence of 1.4 to 4.9 per 100,000 pregnancies. A special group of inherited and acquired coagulation disorders associated with a susceptibility to thrombosis is thrombophilia. Physiological changes during the pregnancy also contribute to the occurrence thromboembolic diseases (VTE) in pregnancy. Total rate of venous thromboembolism is 100 per 100,000 pregnancies and 200 per 100,000 births. Etiopathogenesis of obstetric complications in thrombophilia is not clearly defined, which is one of the reasons for the occasional failure of therapy. In pregnancies with hereditary thrombophilia the oxidative stress is considered to be a cause of complications, similar to preeclampsia. Based on the findings so far, additional research should clarify questions regarding the anticoagulants role in pregnancy loss prevention. In this paper, we analyze the effect of the screening on pregnancy outcomes, consider the justification for the use of anticoagulation therapy in difficult situations, discuss about previous knowledge in the field and argue the use of new specific protocols. In short, we address the justification for prescribing anticoagulants and evaluation of their effect within thrombophilia therapeutic strategies.

Immunologic causes and thrombophilia in recurrent pregnancy loss

Certain miscarriages result from immunologic factors, but there is no clear identification of the precise causes of recurrent pregnancy loss (RPL). Miscarriages and RPL can arise from a disruption of maternal-fetal immune homeostasis. Remodeling of the maternal uterine spiral arteries is one of the key steps for normal growth and development of the fetus. An adequate oxygen supply is necessary for correct placentation, and it is accomplished by proper vascular changes. The development of fetal tissues creates a potential immunologic problem since the fetus can express paternal antigens and, in some cases, antigens of a gamete donor. The maternal immune system actively responds to fetal antigens, and dysregulation of this crosstalk could partly explain pregnancy complications such as miscarriages and RPL. RPL resulting from thrombophilia is primarily due to acquired thrombophilia, and therefore screening and treatment should be focused on antiphospholipid antibody syndrome.

ACOG Practice Bulletin No. 197: Inherited Thrombophilias in Pregnancy

Inherited thrombophilias are associated with an increased risk of venous thromboembolism and 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. This Practice Bulletin has been revised to provide additional information on recommendations for candidates for thrombophilia evaluation, updated consensus guidelines regarding the need for prophylaxis in women with an inherited thrombophilia during pregnancy and the postpartum period, and discussion of new published consensus guidelines from the Society for Obstetric Anesthesia and Perinatology addressing thromboprophylaxis and neuraxial anesthetic considerations in the obstetric population.

Risk factors and role of low molecular weight heparin in obstetric complications among women with inherited thrombophilia - a cohort study

Introduction

Although there is a vast literature regarding the association between inherited thrombophilia, obstetric complications and the effect of low molecular weight heparin (LMWH), these are controversial and we have not found publications related to additional risk factors other than thrombophilia.

Our objectives were to assess the prevalence of miscarriage, placenta-mediated pregnancy complications and fetal loss in pregnant women with IT, establishing associated risk factors and the effect of LMWH.

Materials and methods

A retrospective cohort of pregnant women with IT was formed. Risk factors considered were: high-risk IT, age ≥35 years, body mass index ≥25 and ≥30, assisted reproductive technology, antiphospholipid antibodies, autoimmune disease, first-degree family history of obstetric complications and personal history of venous or arterial thromboembolic disease, the outcomes being M, FL and PMPC.

Results and conclusions

Data from 250 pregnancies in 88 women were obtained.

There were 112 (45%) Ms, 13 (5.2%) FLs and 25 (10%) PMPCs.

High-risk IT was associated with FL (OR = 4.96; 95% CI, 1.42–17.3). Antiphospholipid antibodies and family history of obstetric complications were associated with PMPC (OR = 7.12; 95% CI, 1.89–26.74, OR = 3.88; 95% CI, 1.18–12.78, respectively). The LMWH presented a benefit in the combined outcome (any obstetric complication, OR = 0.25; 95% CI, 0.12–0.54) and M (OR = 0.41; 95% CI, 0.20–0.82).

We conclude that obstetric complications are common in women with IT. Antiphospholipid antibodies, family history of obstetric complications and high-risk IT might be additional risk factors. The LMWH has an apparent protective effect against obstetric complications, which is consistent with some previous studies.

Antiphospholipid antibodies are associated with positive screening for common mental disorders in women with previous pregnancy loss. The NOHA-PSY observational study

OBJECTIVES

Case reports describe neuropsychiatric manifestations associated with antiphospholipid antibodies (aPlAbs). In patients sharing the same symptoms fulfilling the antiphospholipid syndrome (APS) clinical criteria, the prevalence of common mental disorders has, however, never been studied.

METHODS

We observed women with three consecutive abortions before the 10th week of gestation or one foetal loss at or beyond the 10th week. We compared the prevalence of common psychiatric disorders detected through screening using the Mini International Neuropsychiatric Interview, 10 years after inclusion, in women with APS (n = 506), women negative for aPlAbs but carrying the F5rs6025 or F2rs1799963 thrombogenic polymorphism (n = 269), and women with negative thrombophilia screening results as controls (n = 764).

RESULTS

Similar prevalence values were obtained for controls and women bearing one of the two thrombogenic polymorphisms. Women with APS more frequently had mood disorders (relative risk (RR) 1.57 (1.262-1.953), P = .0001) and anxiety (RR 1.645 (1.366-1.979), P < .0001). Within the APS group, lupus anticoagulant (LA) and anti-β2GP1 IgG, or triple positivity, were strong risk factors for mood disorders.

CONCLUSIONS

Women with obstetric APS have a higher risk of positive screening for common mental disorders than women without APS.

THBD sequence variants potentially related to recurrent pregnancy loss

Recurrent pregnancy loss (RPL) is a frequently occurring disease, which is classified as idiopathic in more than 50% of cases. THBD, the endothelial cell receptor for thrombin, has been associated with distinct biological processes and considered a coherent RPL-related candidate gene. In the present study, we have sequenced the complete coding region of THBD in 262 patients affected by RPL. Bioinformatics analysis and screening of controls strongly suggested that the THBD-p.Trp153Gly mutation might be related to RPL aetiology. It could be used, after its validation by functional assays, as a molecular marker for diagnostic/prognostic purposes.

Novel genes and mutations in patients affected by recurrent pregnancy loss

Recurrent pregnancy loss is a frequently occurring human infertility-related disease affecting ~1% of women. It has been estimated that the cause remains unexplained in >50% cases which strongly suggests that genetic factors may contribute towards the phenotype. Concerning its molecular aetiology numerous studies have had limited success in identifying the disease's genetic causes. This might have been due to the fact that hundreds of genes are involved in each physiological step necessary for guaranteeing reproductive success in mammals. In such scenario, next generation sequencing provides a potentially interesting tool for research into recurrent pregnancy loss causative mutations. The present study involved whole-exome sequencing and an innovative bioinformatics analysis, for the first time, in 49 unrelated women affected by recurrent pregnancy loss. We identified 27 coding variants (22 genes) potentially related to the phenotype (41% of patients). The affected genes, which were enriched by potentially deleterious sequence variants, belonged to distinct molecular cascades playing key roles in implantation/pregnancy biology. Using a quantum chemical approach method we established that mutations in MMP-10 and FGA proteins led to substantial energetic modifications suggesting an impact on their functions and/or stability. The next generation sequencing and bioinformatics approaches presented here represent an efficient way to find mutations, having potentially moderate/strong functional effects, associated with recurrent pregnancy loss aetiology. We consider that some of these variants (and genes) represent probable future biomarkers for recurrent pregnancy loss.

Recurrent pregnancy loss: current perspectives

Recurrent pregnancy loss is an important reproductive health issue, affecting 2%–5% of couples. Common established causes include uterine anomalies, antiphospholipid syndrome, hormonal and metabolic disorders, and cytogenetic abnormalities. Other etiologies have been proposed but are still considered controversial, such as chronic endometritis, inherited thrombophilias, luteal phase deficiency, and high sperm DNA fragmentation levels. Over the years, evidence-based treatments such as surgical correction of uterine anomalies or aspirin and heparin for antiphospholipid syndrome have improved the outcomes for couples with recurrent pregnancy loss. However, almost half of the cases remain unexplained and are empirically treated using progesterone supplementation, anticoagulation, and/or immunomodulatory treatments. Regardless of the cause, the long-term prognosis of couples with recurrent pregnancy loss is good, and most eventually achieve a healthy live birth. However, multiple pregnancy losses can have a significant psychological toll on affected couples, and many efforts are being made to improve treatments and decrease the time needed to achieve a successful pregnancy. This article reviews the established and controversial etiologies, and the recommended therapeutic strategies, with a special focus on unexplained recurrent pregnancy losses and the empiric treatments used nowadays. It also discusses the current role of preimplantation genetic testing in the management of recurrent pregnancy loss.

'To test or not to test', the arguments for and against thrombophilia testing in obstetrics

Clinicians increasingly investigate women for thrombophilias due to their associations with venous thromboembolism and placenta-mediated pregnancy complication. These associations, however, are modest and based largely on retrospective data from studies with heterogeneous classifications and populations, leading to discordance between evidence and guidelines. Current evidence suggests a contributory rather than causative role for thrombophilia in placenta-mediated pregnancy complication and venous thromboembolism. With little evidence of benefit from antithrombotic therapy in placenta-mediated pregnancy complication, thrombophilia screening remains controversial. Given the low absolute risk of placenta-mediated pregnancy complication and gestational venous thromboembolism with heritable thrombophilia, universal screening is inappropriate. Selective screening for antiphospholipid syndrome is supported by robust evidence of benefit. Conversely, selective screening for heritable thrombophilia has not been shown to effectively manage placenta-mediated pregnancy complication. Therefore, at present heritable thrombophilia screening is not warranted for placenta-mediated pregnancy complication. Until we have better evidence from better stratified patient groups, caution should remain if we wish to practice evidence-based medicine.

Associations of recurrent miscarriages with chromosomal abnormalities, thrombophilia allelic polymorphisms and/or consanguinity in Saudi Arabia

Background

Recurrent pregnancy loss (RPL) or recurrent spontaneous abortion is an obstetric complication that affects couples at reproductive age. Previous reports documented a clear relationship between parents with chromosomal abnormalities and both recurrent miscarriages and infertility. However, limited data is available from the Arabian Peninsula which is known by higher rates of consanguineous marriages. The main goal of this study was to determine the prevalence of chromosomal abnormalities and thrombophilic polymorphisms, and to correlate them with RPL and consanguinity in Saudi Arabia.

Methods

Cytogenetic analysis of 171 consent patients with RPL was performed by the standard method of 72-h lymphocyte culture and GTG banding. Allelic polymorphisms of three thrombophilic genes (Factor V Leiden, Prothrombin A20210G, MTHFR C677T) were performed using PCR-RFLP (restriction fragment length polymorphism) and gel electrophoresis.

Results

Data analysis revealed that 7.6 % of patients were carrier of numerical or structural chromosomal abnormalities. A high rate of translocations (46 %) was associated to increased incidence of RPL. A significant correlation between consanguineous RPL patients and chromosomal abnormalities (P < 0.05) was found. Both Factor V Leiden and Prothrombin A20210G allelic polymorphisms were significantly associated with a higher prevalence of RPL.

Conclusions

This study demonstrated a strong association between RPL and the prevalence of chromosomal abnormalities and inherited thrombophilia. Given the high rate of consanguineous marriages in the Saudi population, these results underline the importance of systematic cytogenetic investigation and genetic counseling preferably at the premarital stage or at least during early pregnancy phase through preimplantation genetic diagnosis (PGD).

Antiphospholipid antibodies and the risk of severe and non-severe pre-eclampsia: the NOHA case-control study

BACKGROUND

pre-eclampsia (PEecl) can be defined as non-severe (NS-PEecl) or severe (S-PEecl). Our study aimed to determine the incidence of antiphospholipid antibodies (aPLs) in women with a past history of NS-PEecl or S-PEecl.

PATIENTS AND METHODS

This case-control study includes 195 control women, 199 NS-PEecl patients and 143 S-PEecl patients whose plasma samples were collected 6 months after their first delivery. Each plasma was tested for lupus anticoagulant (LA), anticardiolipin (aCL) and antiβ2GP1 antibodies, as well as antibodies against phosphatidylserine/prothrombin complex (aPS/PT) and domain I of the β2GP1.

RESULTS

When compared with the control group no significant associations were found for the NS-PEecl group after adjustment of confounding variables. For the S-PEecl group, there was an association with antiβ2GP1 immunoglobulin G (IgG) (OR 16.91, 95% CI 3.71-77.06), as well as age, obesity, smoking and multiparity. Antiβ2GP1-domain I IgG was associated with aCL, antiβ2GP1 and aPS/PT IgG in the three groups. aPS/PT IgG was associated with aCL IgG, and aPS/PT IgM was associated with aCL and antiβ2GP1 IgM in the three groups.

CONCLUSION

S-PEecl is a distinct entity from NS-PEecl and is mainly associated with the presence of antiβ2GP1 IgG. Antiβ2GP1 domain I correlates with other aPL IgG tests, and aPS/PT may be promising in patients for whom LA tests cannot be interpreted.

Maternal thrombophilia and adverse pregnancy outcome: a case-control study

OBJECTIVE

To assess the risk of adverse pregnancy outcomes in patients with acquired and/or congenital thrombophilia factors.

PATIENTS AND METHODS

A cohort of 130 women with a history of pregnancy loss and no successful gestation were investigated for the presence of congenital and acquired thrombophilia factors, and then compared with a control group of 130 healthy women who had had at least one successful gestation and no pregnancy loss, and were screened for congenital and acquired thrombophilia factors.

RESULTS

Acquired and congenital thrombophilia factors were found in 30 (23%) patients and in 14 (10.8%) controls (p < 0.015). The presence of ≥1 congenital thrombophilia factor was associated with pregnancy loss with an odds ratio of 2.46 (p = 0.040). Moreover, women who had had >1 early fetal loss had a 2.85-fold risk of being carriers of congenital thrombophilia factors, compared to the controls.

CONCLUSION

Our study showed the increased risk of miscarriage in patients with congenital thrombophilia factors and >1 early fetal loss.

Antithrombotic treatment for pregnancy complications: which path for the journey to precision medicine?

Haemostatic and vascular biology mechanisms appear to play an important role in the pathogenesis of placenta-mediated pregnancy complications. Although low-dose aspirin (LDA) has a modest effect in preventing preeclampsia, antithrombotic interventions, LDA and low molecular weight heparin (LMWH) have not definitively proven their effectiveness in women with placenta-mediated pregnancy complications selected by previous pregnancy outcome alone. Given the heterogeneous aetiology of placenta-mediated pregnancy complications, it is critical to stratify patients according to maternal and fetal characteristics and disease mechanisms rather than simply by pregnancy outcome, such as miscarriage. Such stratification could identify those who could benefit from antithrombotic interventions in pregnancy. We lack data on genome-wide association studies, biomarkers and trials of interventions applied to specific homogeneous populations. Future studies should focus on elaborating different disease mechanisms and examining antithrombotic interventions in specific and more homogeneous groups, such as thrombophilic women with well-characterized placenta-mediated pregnancy complications, stratified by disease severity and pathological findings. Because of fetal safety concerns with new anticoagulants, the intervention should focus on heparins alone or in combination with LDA. Thus, placenta-mediated pregnancy complications deserve precision medicine, defining disease by mechanism rather than outcome with interventions focused on a more personalized approach.

The role of thrombophilia in pregnancy

Thrombotic disease is a major cause of peripartum morbidity and mortality worldwide. Development of thrombosis in pregnancy is multifactorial due to the physiologic changes of pregnancy—which induce a relative hypercoagulable state—as well as physical changes leading to increased stasis and also the effects of both the inherited and the acquired thrombophilias. In this review, we discuss the impact of each of these factors on the development of thrombosis as well as the evidence for the impact of pregnancy-associated thrombosis on pregnancy outcome. We then discuss the use of both prophylactic and therapeutic anticoagulation during pregnancy and the puerperium. We review the indications and dosing recommendations for administration of anticoagulation in a context of discussing the evidence including the lack of evidence and formal guidelines in this area. We briefly address the role of the new oral anticoagulants in pregnancy and conclude that significant further research in women with thrombophilias and pregnancy-associated thrombosis may help clarify the management of this condition in the future.

Fetoplacental discrepancy with normal karyotype in amniotic fluid and two different cell lines in placenta

We present a case of fetoplacental discrepancy in a second-trimester fetus with normal karyotype in amniotic fluid and two different Robertsonian translocations in placenta. A 41-year-old woman of Middle-Eastern origin, gravida 2, para 1, underwent amniocentesis at 16-week gestation because of advanced maternal age. Amniotic fluid karyotype showed a normal 46,XX karyotype with a homozygous inv(9). Parental chromosome analysis showed both parents to be carriers of inv(9) and the parents are not consanguineous. Fetal ultrasound was normal. The mother presented to the clinic 4 weeks later with intrauterine fetal demise. Chromosome analysis from the placenta showed two different cell lines: a balanced (15;21) Roberstonian translocation in 11 cells and an unbalanced (21;21) Robertsonian translocation in 9 cells. The karyotype was interpreted as mos 45,XX,inv(9)(p11q13)x2,der(15;21)(q10;q10)[11]/46,XX,inv(9)(p11q13)x2,+21,der(21;21)(q10;q10). Mother was a carrier for the Cystic Fibrosis (delta F508), Factor V Leiden mutations, HbD-Los Angeles and HbQ-India variants. She also had a sibling with term stillbirth. Her husband's history was unremarkable. Our case appears to be another example of confined placental mosaicism (CPM) with normal fetal karyotype. However, we could not confirm the possibility that CPM contributed to the IUFD in our case given the complex medical history of the mother.

Recurrent miscarriage and thrombophilia: an update

PURPOSE OF REVIEW

Acquired and inherited thrombophilia is an important research avenue in the recurrent miscarriage field. The optimum treatment for patients with recurrent miscarriage and a confirmed thrombophilia remains a contentious issue. We aim to appraise and explore the latest research in the field of thrombophilia and recurrent miscarriage in this review.

RECENT FINDINGS

Antiphospholipid syndrome (APS) is the only proven thrombophilia that is associated with adverse pregnancy outcomes. Research involving inherited thrombophilia and recurrent miscarriage is limited to small observational studies with small and heterogeneous populations. Aspirin and heparin therapy are frequently prescribed for APS, yet there is no robust evidence for the most efficacious regime. The combination of inherited hypercoagulability and environmental factors in association with recurrent miscarriage has recently been explored as an aid to identify high-risk individuals.

SUMMARY

The cause of recurrent miscarriage is multifactorial and appropriate treatment continues to be a challenge. Laboratory tests need to be standardized and well designed multicentre research trials are essential to expand on the current knowledge base with the aim to produce strong evidence-based medicine.

Evaluation and treatment of recurrent pregnancy loss: a committee opinion

The majority of miscarriages are sporadic and most result from genetic causes that are greatly influenced by maternal age. Recurrent pregnancy loss (RPL) is defined by two or more failed clinical pregnancies, and up to 50% of cases of RPL will not have a clearly defined etiology.

Factor V Leiden thrombophilia

Factor V Leiden is a genetic disorder characterized by a poor anticoagulant response to activated Protein C and an increased risk for venous thromboembolism. Deep venous thrombosis and pulmonary embolism are the most common manifestations, but thrombosis in unusual locations also occurs. The current evidence suggests that the mutation has at most a modest effect on recurrence risk after initial treatment of a first venous thromboembolism. Factor V Leiden is also associated with a 2- to 3-fold increased relative risk for pregnancy loss and possibly other obstetric complications, although the probability of a successful pregnancy outcome is high. The clinical expression of Factor V Leiden is influenced by the number of Factor V Leiden alleles, coexisting genetic and acquired thrombophilic disorders, and circumstantial risk factors. Diagnosis requires the activated Protein C resistance assay (a coagulation screening test) or DNA analysis of the F5 gene, which encodes the Factor V protein. The first acute thrombosis is treated according to standard guidelines. Decisions regarding the optimal duration of anticoagulation are based on an individualized assessment of the risks for venous thromboembolism recurrence and anticoagulant-related bleeding. In the absence of a history of thrombosis, long-term anticoagulation is not routinely recommended for asymptomatic Factor V Leiden heterozygotes, although prophylactic anticoagulation may be considered in high-risk clinical settings. In the absence of evidence that early diagnosis reduces morbidity or mortality, decisions regarding testing at-risk family members should be made on an individual basis.

A common polymorphism in NR1H2 (LXRbeta) is associated with preeclampsia

Background

Preeclampsia is a frequent complication of pregnancy and a leading cause of perinatal mortality. Both genetic and environmental risk factors have been identified. Lipid metabolism, particularly cholesterol metabolism, is associated with this disease. Liver X receptors alpha (NR1H3, also known as LXRalpha) and beta (NR1H2, also known as LXRbeta) play a key role in lipid metabolism. They belong to the nuclear receptor superfamily and are activated by cholesterol derivatives. They have been implicated in preeclampsia because they modulate trophoblast invasion and regulate the expression of the endoglin (CD105) gene, a marker of preeclampsia. The aim of this study was to investigate associations between the NR1H3 and NR1H2 genes and preeclampsia.

Methods

We assessed associations between single nucleotide polymorphisms of NR1H3 (rs2279238 and rs7120118) and NR1H2 (rs35463555 and rs2695121) and the disease in 155 individuals with preeclampsia and 305 controls. Genotypes were determined by high-resolution melting analysis. We then used a logistic regression model to analyze the different alleles and genotypes for those polymorphisms as a function of case/control status.

Results

We found no association between NR1H3 SNPs and the disease, but the NR1H2 polymorphism rs2695121 was found to be strongly associated with preeclampsia (genotype C/C: adjusted odds ratio, 2.05; 95% CI, 1.04-4.05; p = 0.039 and genotype T/C: adjusted odds ratio, 1.85; 95% CI, 1.01-3.42; p = 0.049).

Conclusions

This study provides the first evidence of an association between the NR1H2 gene and preeclampsia, adding to our understanding of the links between cholesterol metabolism and this disease.

Addition of enoxaparin to aspirin for the secondary prevention of placental vascular complications in women with severe pre-eclampsia. The pilot randomised controlled NOH-PE trial

Administration of heparin in the secondary prevention of placental vascular complications is still experimental. In women with a previous severe pre-eclampsia, we investigated the effectiveness of enoxaparin, a low-molecular-weight heparin, in preventing these complications. Between January 2000 and January 2010, 224 women from the NOHA First cohort, with previous severe pre-eclampsia but no foetal loss during their first pregnancy and negative for antiphospholipid antibodies, were randomised to either a prophylactic daily dose of enoxaparin starting from the positive pregnancy test (n=112), or no enoxaparin (n=112). The primary outcome was a composite of at least one of the following: pre-eclampsia, abruptio placentae, birthweight ≤ 5th percentile, or foetal loss after 20 weeks. Enoxaparin was associated with a lower frequency of primary outcome: 8.9% (n=10/112) vs. 25 % (28/112), p=0.004, hazard ratio = 0.32, 95% confidence interval (0.16-0.66), p=0.002. Enoxaparin was safe, with no obvious side-effect, no thrombocytopenia nor major bleeding event excess. This pilot study shows that enoxaparin given early during the second pregnancy decreases the occurrence of placental vascular complications in women with a previous severe pre-eclampsia during their first pregnancy.

Can Factor V Leiden and prothrombin G20210A testing in women with recurrent pregnancy loss result in improved pregnancy outcomes?: Results from a targeted evidence-based review

Women with recurrent pregnancy loss are offered Factor V Leiden (F5) and/or prothrombin G20210A (F2) testing to identify candidates for anticoagulation to improve outcomes. A systematic literature review was performed to estimate test performance, effect sizes, and treatment effectiveness. Electronic searches were performed through April 2011, with review of references from included articles. English-language studies addressed analytic validity, clinical validity, and/or clinical utility and satisfied predefined inclusion criteria. Adequate evidence showed high analytic sensitivity and specificity for F5 and F2 testing. Evidence for clinical validity was adequate. The summary odds ratio for association of recurrent pregnancy loss with F5 in case-controlled studies was 2.02 (95% confidence interval, 1.60-2.55), with moderate heterogeneity and suggestion of publication bias. Longitudinal studies in women with recurrent pregnancy loss or unselected cohorts showed F5 carriers were more likely to have a subsequent loss than noncarriers (odds ratios: 1.93 and 2.03, respectively). Results for F2 testing were similar. For clinical utility, evidence was adequate that anticoagulation treatments were ineffective (except in antiphospholipid antibody syndrome) and had treatment-associated harms. The certainty of evidence is moderate (high, moderate, and low) that anticoagulation of women with recurrent pregnancy loss and F5/F2 variants would currently lead to net harms.

Impact of common thrombophilias and JAK2 V617F on pregnancy outcomes in unselected Italian women

BACKGROUND

Although an association between thrombophilias and adverse pregnancy outcome has been shown, the influence of the most common inherited thrombophilias and the somatic mutation JAK2 V617F in determining an adverse outcome is questioned.

OBJECTIVES

We examined the contribution of the factor V Leiden (FVL), the prothrombin G20210A (PTm) and the somatic JAK2 V617F mutations to adverse pregnancy outcome in an unselected cohort of pregnant women.

PATIENTS/METHODS

During the study period, 5345 pregnant women were admitted to the 14 hospitals of the five provinces of the Campania region (Italy). Of these, 3097 samples were investigated and obstetric history collected. The presence of the FVL, PTm, and JAK2 V617F mutation was prospectively determined by polymerase chain reaction followed by TaqMan SNP genotyping assays.

RESULTS AND CONCLUSIONS

We identified 119 (3.8%) women that carried FVL and 138 (4.4%) with the PTm. Only 4 (0.1%) women carried both mutations. Only one woman tested positive for the JAK2 V617F somatic mutation. The prevalence of a previous history of an adverse pregnancy outcome was similar in women with common thrombophilias as compared to those without. In the current pregnancy, there was no association of any of the genetic markers considered with any of the adverse outcomes investigated. Carriership of FVL or PTm showed a positive trend with delivery of a small for gestational age newborn (OR: 1.5, 95% CI: 0.9-2.5). Pregnancy outcomes in asymptomatic women with inherited thrombophilias are often uneventful. Therefore, in women at low-risk of an adverse pregnancy, neither screening for common thrombophilias nor administration of routine thromboprophylaxis are warranted.

Coagulation disorders in pregnancy: acquired and inherited thrombophilias

Both acquired and inherited thrombophilias are associated with an increased risk of pregnancy-related venous thromboembolism (VTE) as well as with adverse pregnancy outcome. However, the extension of attributable risk for each thrombophilia and outcome is still a question of debate. Thrombophilias have been investigated in connection with VTE and pregnancy complications such as: recurrent and nonrecurrent early pregnancy loss, late fetal death, placental abruption, fetal growth restriction, and preeclampsia. This review discusses the evidence of association between thrombophilias and pregnancy outcome together with issues as to clinical management and preventive strategies.

Paternal endothelial protein C receptor 219Gly variant as a mild and limited risk factor for deep vein thrombosis during pregnancy

BACKGROUND

Half of all venous thromboembolism (VTE) cases during pregnancy are associated with a maternal thrombophilia. The influence of paternal genotype on the placenta and in the genesis of VTE has not been described.

OBJECTIVES

To determine if the maternal and paternal Ser219Gly dimorphism of the endothelial protein C receptor (EPCR), evaluated through detection of the PROCR 6936G allele, is a risk factor for VTE during pregnancy.

METHODS

Using a case-control study nested in the NOHA first cohort of primigravidae, 66 patient couples with a first episode of gestational VTE and randomly selected non-thrombotic control couples were investigated. For each couple, factor V gene (F5) G1691A, factor II gene (F2) G20210A, factor XII gene (F12) C46T and PROCR A6936G polymorphisms were determined.

RESULTS

Only maternal F5 1691A, F2 20210A and F12 46T alleles were independently associated with iliac and infra-iliac deep vein thromboses (DVT). The maternal PROCR 6936G allele was a mild risk factor for iliac DVT (OR = 5.5 [2.3-13.0]). The paternal PROCR 6936G allele was also a mild independent risk factor for iliac DVT (OR = 2.6 [1.1-6.2]) and only during pregnancy (rather than postpartum) among maternal carriers of the F5 1691A allele (OR = 77.6 [4.2 to > 999.9]).

CONCLUSIONS

The paternal PROCR 6936G allele could be a risk factor for maternal iliac DVT. Its impact was milder than the F5 1691A and F2 20210A polymorphisms in mothers. We hypothesize that the prothrombotic effect of the paternal PROCR 6936G allele is localized. Therefore, DVT during pregnancy may be influenced by trophoblastic cell-surface proteins inherited from both maternal and paternal alleles.

Observational study of pregnant women with a previous spontaneous abortion before the 10th gestation week with and without antiphospholipid antibodies

BACKGROUND

A clinical subtype of purely obstetrical antiphospholipid antibody (aPL-Ab) syndrome (APS) requires three or more unexplained consecutive embryonic losses before the 10th week of gestation associated with persistently positive lupus anticoagulant (LAC), and/or anticardiolipin IgG or IgM, and/or anti-beta2-glycoprotein I (abeta2GpI) IgG or IgM. Although this diagnostic classification of APS appeared to be the most sensitive, the APS-associated serological criteria are still debated.

PATIENTS/METHODS

We prospectively observed the second pregnancy of 284 women with a previous embryonic loss, both with and without aPL-Ab.

RESULTS

aPL-Ab-positive women were more prone to pregnancy loss, embryonic loss, pre-eclampsia, placental abruption and intrauterine fetal growth restriction. Type IIa aPL-Ab positivity (LAC present alone) was associated with the highest risk of recurrent embryonic loss and intrauterine growth restriction. Type I aPL-Ab positivity (combinations of aPL-Ab type positivity) was associated with the strongest risks of late complications, pre-eclampsia and placental abruption. Finally, abeta2GpI-M positivities were not clinically relevant in these women.

CONCLUSION

Patients with a first unexplained pregnancy loss before the 10th week of gestation who are also positive for aPL-Abs have a higher risk of various complications in their second pregnancy. In this study, measurement of abeta2GpI-M had a questionable prognostic value.

Consultative hematology: the pregnant patient pregnancy loss

The presence of antiphospholipid antibodies has been associated with an increased risk of recurrent pregnancy loss, and there is evidence to suggest that antithrombotic therapy improves the likelihood of a successful outcome in affected women. Recent studies suggest an association between hereditary thrombophilia and pregnancy loss, although a causal role remains controversial. Although the available data are limited and flawed, there is increasing use of antithrombotic therapy in thrombophilic women with a history of pregnancy failure. Given the absence of proven effective therapy in women with unexplained recurrent loss, there is also growing pressure to intervene with antithrombotics in women with no known underlying thrombophilia. This article reviews the evidence for an association between thrombophilia and recurrent pregnancy loss and the data regarding the use of antithrombotic therapy for prevention of loss-an area that remains particularly challenging because of the paucity of good quality data upon which to base clinical decisions.

Inherited Thrombophilia is Associated With Pregnancy Losses That Occur After 12th Gestational Week in Serbian Population

Recurrent fetal loss (RFL) is a significant clinical problem, occurring in 1% to 5% of reproductive females. Inherited or acquired thrombophilia has been diagnosed in 50% to 65% of women with history of unexplained fetal loss. The objective of our study was to determine the prevalence of thrombophilia in women with unexplained RFL in Serbian population and to find out whether the presence of thrombophilia is associated with pregnancy losses that occur later than 12th gestational week. We have examined 147 women with unexplained RFL or intrauterine fetal death and 128 healthy women with at least 1 uncomplicated pregnancy. The antithrombin (AT), protein C (PC), protein S (PS), activated protein C (APC) resistance, factor V (FV) G1691A, factor II (FII) G20210A, and MTHFR C677T were determined. At least 1 inherited thrombophilic defect was found in 54 (36.7%) of 147 women with repeated fetal losses and in 11 (8.59%) of 128 controls (P < .001, OR 6.17, 95% CI 3.06-12.48). The most common thrombophilic abnormalities were homozygosity for MTHFR 677TT, FV Leiden, and FII G20210A. Deficiency of natural anticoagulants occurred in 10 patients, with protein S deficiency being the most frequent one. Thrombophilia was found in 46 of 94 women with RFL that occurred later than the 12th gestational week and in only 8 of 53 with RPL earlier than 12th week (P = .001). Our study has shown the association between the hereditary thrombophilia and RFL that occurred after the 12th gestational week in Serbian population.

Thrombophilia risk factors are associated with intrauterine foetal death and pregnancy-related venous thromboembolism

Pregnancy in healthy women is accompanied by hypercoagulable changes that may interact with thrombophilia risk factors and threaten pregnancy. However, the literature on this issue is conflicting. In investigating the relationship between pregnancy-associated complications and the presence of thrombophilia risk factors, we studied the records of 414 women who had been examined for inherited and acquired thrombophilia in the period 1996 to 2006 because of pregnancy-associated complications. Of a total of 885 pregnancies among the women, 397 were recorded as foetal loss/intrauterine foetal death during the first (62 %), second (25 %) or third trimester (13 %). One-hundred-and-two (25 %) women had had a thromboembolic event during one of their pregnancies, and 98 (24 %) had had pre-eclampsia on at least one occasion. Intrauterine growth restriction was found in 105 (25 %) of the women, and 29 (7 %) suffered placental abruption. We found that 120 (29 %) women had at least one thrombophilia risk factor. Factor V Leiden heterozygosity was the most common thrombophilia factor (n = 52), mostly linked with the risk of venous thromboembolism during pregnancy or postpartum and to foetal death during the second or third trimester. Fifty-three (13 %) women had antiphospholipid antibodies (lupus anticoagulant and/or anti-beta2-glycoprotein 1 antibodies) mainly associated with the risk of spontaneous abortion during the first trimester. In conclusion, thrombophilia was found to be considerably more common in women with pregnancy-associated complications in comparison with the general population, and most frequently in conjunction with venous thromboembolism during pregnancy and the postpartum period.

Interleukin 10 gene promoter polymorphisms in women with pregnancy loss: preferential association with embryonic wastage

Interleukin 10 (IL10) is associated with maternal immunotolerance. IL10 also down-regulates decidual cell tissue factor expression, the main molecule triggering coagulation activation: this antithrombotic effect may protect the umbilicoplacental vasculature from the 10th wk of gestation onward. IL10 down-regulation may thus dispose to early pregnancy loss (PL) due to maternal immunotolerance defect or late pregnancy failure due to placental vascular insufficiency. IL10 gene promoter polymorphisms associated with cytokine down-regulation may help to identify the actual and probable mechanisms of IL10 modulation in pregnancy outcomes. We investigated the following four IL10 promoter polymorphisms associated with IL10 down-regulation: two single-nucleotide polymorphisms rs1800871 and rs1800872 and two polymorphic CA repeat microsatellites IL10 X78437.2:g8134CA(14_29) and IL10 X78437.2:g.5325CA(11_15). Each microsatellite was analyzed as a biallelic polymorphism. Based on a review of the literature, we define a short allele and a long allele for each microsatellite. We compared their frequencies in early PL occurring before 10 wk of amenorrhea (n = 342) and in PL occurring later on (n = 123). The mutated alleles rs1800871T (odds ratio, 3.083; 95% confidence interval, 1.984-4.792) and rs1800872A (odds ratio, 3.013; 95% confidence interval, 1.924-4.719) were associated with early PL. The haplotype rs1800872A/rs1800871T/X78437.2:g.8134CA[14_25]/X78437.2:g.5325CA[11_13], which includes the two mutated alleles, was significantly associated with the risk of early PL in a dose-dependent manner. Positivity for one haplotype was significantly associated with a 5.6-fold increase in the risk of early pregnancy failure, and positivity for two haplotypes was associated with an 8-fold increase in risk. In women with PL, some polymorphisms of the IL10 gene promoter seem to be constitutional risk factors for early (embryonic) pregnancy failure.

Inherited thrombophilias and unexplained pregnancy loss: an incident case-control study

BACKGROUND

Despite an initial impressive impact, a critical appraisal of the link between pregnancy loss and inherited thrombophilias is currently growing. Furthermore, little is known about the paternal thrombophilic phenotype and pregnancy loss.

OBJECTIVE

We sought an association between unexplained pregnancy loss and parental factor V Leiden (FVL) and Prothrombin G20210A (PTG) mutations.

METHODS

Design - Incident case-control study. Setting- University Hospital of Brest (France). Patients - Women and their partners from the West Brittany area, consecutively referred for unexplained pregnancy losses (two or more consecutive losses at or before 21 weeks of gestation, or at least one later loss). Controls - Women and their partners with no history of pregnancy loss and at least one normal pregnancy, from the same geographic area, recruited using electoral lists. Statistical analysis - Comparison of FVL and PTG allele frequency between cases and controls using the chi-square test. Separate analyses were performed according to the type of pregnancy loss (early recurrent or later loss).

RESULTS

311 women (mean age: 32.8) and 284 of their partners were enrolled as cases while 599 women (mean age: 34.3) and 297 of their partners were recruited as controls. The prevalence of female, male or couple thrombophilic mutations was not statistically different between cases and controls whatever the definition of pregnancy loss retained.

CONCLUSIONS

Presently, there is no clinical indication to routinely test for FVL and likely PTG mutations in women with early recurrent pregnancy loss. Moreover, our results did not reveal that paternal thrombophilic polymorphism should be further explored.

Some hemostasis variables at the end of the population distributions are risk factors for severe postpartum hemorrhages

BACKGROUND

Severe postpartum hemorrhages (PPH) represent a significant cause of maternal morbidity/mortality, but little is known about its hemostasis-related risk factors. Among the 32 463 women enrolled in the NOHA First cohort, 317 developed severe PPH (S-PPH group), 1269 non-severe PPH (NS-PPH group) and the remaining individuals were considered as control women (C group).

METHODS

We performed a case-control study, including 317 triplets of women allocated from the three groups that shared the same clinical characteristics as the S-PPH group.

RESULTS

From values obtained 6-9 months after delivery, low (but not-deficient) levels of fibrinogen, von Willebrand factor (VWF) antigen, factor (F) XI, platelet CD42b, TRAP-induced increase of platelet CD41a and high values of serum residual prothrombin activity or closure aperture times using the collagen-ADP cartridge on the PFA-100 system, and blood group O, were independently associated with a significant risk of severe PPH. Being positive for at least two of these eight variables was found in 1.6%, 3.5% and 20.8% of the women from the C, the NS-PPH and the S-PPH groups, respectively, the odds ratio for S-PPH in such a case being 16.4, 95%CI (6.5-41), P < 0.0001.

CONCLUSIONS

Women with some hemostasis-related variables at the low or high end of the population distributions are prone to the severe forms of PPH. Clinical trials will allow us to know if acting on these risk factors can lower the clinical severity of PPH.

Venous thromboembolism, thrombophilia, antithrombotic therapy, and pregnancy: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines (8th Edition)

This article discusses the management of venous thromboembolism (VTE) and thrombophilia, as well as the use of antithrombotic agents, during pregnancy and is part of the American College of Chest Physicians Evidence-Based Clinical Practice Guidelines (8th Edition). Grade 1 recommendations are strong and indicate that benefits do, or do not, outweigh risks, burden, and costs. Grade 2 recommendations are weaker and imply that the magnitude of the benefits and risks, burden, and costs are less certain. Support for recommendations may come from high-quality, moderate-quality or low-quality studies; labeled, respectively, A, B, and C. Among the key recommendations in this chapter are the following: for pregnant women, in general, we recommend that vitamin K antagonists should be substituted with unfractionated heparin (UFH) or low-molecular-weight heparin (LMWH) [Grade 1A], except perhaps in women with mechanical heart valves. For pregnant patients, we suggest LMWH over UFH for the prevention and treatment of VTE (Grade 2C). For pregnant women with acute VTE, we recommend that subcutaneous LMWH or UFH should be continued throughout pregnancy (Grade 1B) and suggest that anticoagulants should be continued for at least 6 weeks postpartum (for a total minimum duration of therapy of 6 months) [Grade 2C]. For pregnant patients with a single prior episode of VTE associated with a transient risk factor that is no longer present and no thrombophilia, we recommend clinical surveillance antepartum and anticoagulant prophylaxis postpartum (Grade 1C). For other pregnant women with a history of a single prior episode of VTE who are not receiving long-term anticoagulant therapy, we recommend one of the following, rather than routine care or full-dose anticoagulation: antepartum prophylactic LMWH/UFH or intermediate-dose LMWH/UFH or clinical surveillance throughout pregnancy plus postpartum anticoagulants (Grade 1C). For such patients with a higher risk thrombophilia, in addition to postpartum prophylaxis, we suggest antepartum prophylactic or intermediate-dose LMWH or prophylactic or intermediate-dose UFH, rather than clinical surveillance (Grade 2C). We suggest that pregnant women with multiple episodes of VTE who are not receiving long-term anticoagulants receive antepartum prophylactic, intermediate-dose, or adjusted-dose LMWH or intermediate or adjusted-dose UFH, followed by postpartum anticoagulants (Grade 2C). For those pregnant women with prior VTE who are receiving long-term anticoagulants, we recommend LMWH or UFH throughout pregnancy (either adjusted-dose LMWH or UFH, 75% of adjusted-dose LMWH, or intermediate-dose LMWH) followed by resumption of long-term anticoagulants postpartum (Grade 1C). We suggest both antepartum and postpartum prophylaxis for pregnant women with no prior history of VTE but antithrombin deficiency (Grade 2C). For all other pregnant women with thrombophilia but no prior VTE, we suggest antepartum clinical surveillance or prophylactic LMWH or UFH, plus postpartum anticoagulants, rather than routine care (Grade 2C). For women with recurrent early pregnancy loss or unexplained late pregnancy loss, we recommend screening for antiphospholipid antibodies (APLAs) [Grade 1A]. For women with these pregnancy complications who test positive for APLAs and have no history of venous or arterial thrombosis, we recommend antepartum administration of prophylactic or intermediate-dose UFH or prophylactic LMWH combined with aspirin (Grade 1B). We recommend that the decision about anticoagulant management during pregnancy for pregnant women with mechanical heart valves include an assessment of additional risk factors for thromboembolism including valve type, position, and history of thromboembolism (Grade 1C). While patient values and preferences are important for all decisions regarding antithrombotic therapy in pregnancy, this is particularly so for women with mechanical heart valves. For these women, we recommend either adjusted-dose bid LMWH throughout pregnancy (Grade 1C), adjusted-dose UFH throughout pregnancy (Grade 1C), or one of these two regimens until the thirteenth week with warfarin substitution until close to delivery before restarting LMWH or UFH) [Grade 1C]. However, if a pregnant woman with a mechanical heart valve is judged to be at very high risk of thromboembolism and there are concerns about the efficacy and safety of LMWH or UFH as dosed above, we suggest vitamin K antagonists throughout pregnancy with replacement by UFH or LMWH close to delivery, after a thorough discussion of the potential risks and benefits of this approach (Grade 2C).

FV-Leiden- und Prothrombin-G20210A-Mutation

Die Faktor-V-Leiden-Mutation und die Prothrombin-G20210A-Mutation sind mit einer Inzidenz von 2–4% und etwa 1% die häufigsten genetisch determinierten thrombophilen Risikofaktoren. Während der thrombophile Mechanismus der FV-Leiden-Mutation auf einer Hemmung der antikoagulatorischen Aktivität von aktiviertem Protein C (APC) beruht, ist der molekulare Mechanismus der Prothrombin-G20210A-Mutation nicht eindeutig geklärt. Das Vorliegen beider Mutationen erhöht das Risiko für eine venöse Thrombose, hat aber keinen wesentlichen Einfluss auf das Rezidivrisiko nach einer spontanen venösen Thrombose. Deswegen kann der Mutationsnachweis die klinische Diagnose einer Thrombophilie zwar bestätigen, beeinflusst aber – bis auf homozygote und compound-heterozygote Mutationsträger – das therapeutische Vorgehen nicht.

Factor V Leiden mutation: a treatable etiology for sporadic and recurrent pregnancy loss

OBJECTIVE

We hypothesized that the thrombophilic G1691A factor V Leiden (FVL) gene mutation was a common, significant, and treatable cause of sporadic and recurrent pregnancy loss (RPL).

DESIGN

We compared the frequency of the FVL mutation in 141 women with >or=1 pregnancy and 1 sporadic pregnancy loss (308 live births, 141 pregnancy losses), 44 women with >or=1 pregnancy and >or=3 pregnancy losses (105 live births, 180 pregnancy losses), and 638 women with >or=1 live birth pregnancy and 0 pregnancy loss (1553 live births).

SETTING

Outpatient Clinical Research Center.

PATIENT(S)

A total of 823 caucasian women with consecutive measures of the FVL mutation.

MAIN OUTCOME MEASURE(S)

We used polymerase chain reaction techniques to characterize the thrombophilic FVL G1691A gene mutation.

RESULT(S)

Of the 638 controls, 47 (7.4%) had FVL heterozygosity versus 16 heterozygous and 2 homozygous FVL cases (18/141, 12.8%) in 141 women with 1 sporadic pregnancy loss versus 9/44 RPL cases (20.5%, 8 heterozygous and 1 homozygous FVL). The FVL frequency in cases with 1 sporadic pregnancy loss (18/141, 12.8%) did not differ from RPL cases (9/44, 20.45%).

CONCLUSION(S)

After unexplained sporadic pregnancy loss, as well as after RPL, to provide the option to prospectively optimize subsequent live birth outcomes with low-molecular-weight heparin thromboprophylaxis, we suggest that measurements be done of the FVL mutation, a treatable etiology for sporadic pregnancy loss as well as for RPL.

Thrombophilia and adverse pregnancy outcome

This article focuses on the clinical evaluation and management of women who have thrombophilia-related placental vascular complications, including fetal loss, pre-eclampsia, intrauterine fetal growth restriction, and placental abruption. All are major causes of maternal and fetal adverse outcomes.