Resistance to activated protein C and impaired TFPI activity in women with previous hormone-induced venous thromboembolism

INTRODUCTION

Hormonal contraception is a well-known risk factor for venous thromboembolism (VTE). APC resistance and impaired functions of protein S and TFPI are thought to play an important role in the pathogenesis of hormone-related VTE. It is unknown, whether women, who develop VTE during hormonal contraception possess a vulnerability in these pathways, making them susceptible to thrombosis.

MATERIALS AND METHODS

Plasma samples were obtained from 57 premenopausal women in average 15.3 years after hormone-associated VTE and from 31 healthy controls. Thrombin generation at high tissue factor (TF) in the absence and in the presence of activated protein C (APC) and at low TF without and with inhibiting anti-protein S- and anti-TFPI-antibodies was measured via calibrated automated thrombography.

RESULTS

Women with previous hormone-related thrombosis had higher thrombin generation at low TF, higher APC resistance, protein S- and TFPI ratios, differences: 219.9 nM IIa.min (95%CI:90.4 to 349.3); 1.88 (95%CI:0.71 to 3.05); 0.13 (95%CI:0.01 to 0.26) and 0.19 (95%CI:0.08 to 0.30), respectively. Thrombin generation at high TF without APC did not differ between the groups. Smoking decreased thrombin generation at low TF by -222.6 nM IIa.min (95%CI: -381.1 to -64.1), the APC sensitivity ratio by -2.20 (95%CI: -3.63 to -0.77) and the TFPI ratio by -0.16 (95%CI: -0.29 to -0.03), but did not influence thrombin generation at high TF.

DISCUSSION

We demonstrated impairment of the protein S/TFPI system and increased APC resistance in women with previous hormone-induced VTE. Smoking decreased thrombin generation at assay conditions, dependent on the function of the TFPI system.

The presence of lupus nephritis additionally increases the risk of preeclampsia among pregnant women with systemic lupus erythematosus

Introduction

Pregnant women with systematic lupus erythematosus (SLE) have an increased risk of obstetric complications, such as preeclampsia and premature births. Previous studies have suggested that renal involvement could further increase the risk for adverse obstetric outcomes. Aims: The aim of this study was to compare the obstetric outcomes in a Swedish cohort of patients with SLE with and without lupus nephritis (LN).

Patients and methods

The study was conducted as a retrospective observational study on 103 women with SLE, who gave birth at the Karolinska University Hospital between the years 2000-2017. Thirty-five women had previous or active LN and 68 women had non-renal lupus. Data was collected from digital medical records. The outcomes that were analysed included infants born small for gestational age (SGA), premature birth, preeclampsia, SLE- or nephritis flare and caesarean section.

Results

Women with LN, both with previous and with renal flare during pregnancy suffered from pre-eclampsia more often compared to women with non-renal lupus (25.7% vs 2.9%, p = 0.001) and this complication was associated with premature birth (p = 0.021) and caesarean section (p = 0.035).

Conclusions

Lupus nephritis is a significant risk factor for adverse obstetric outcomes in women with SLE, including preeclampsia. Those patients could benefit from more frequent antenatal controls and more vigorous follow-up.

The impact of cardiovascular diseases on maternal deaths in the Nordic countries

INTRODUCTION

Cardiovascular diseases have become increasingly important as a cause of maternal death in the Nordic countries. This is likely to be associated with a rising incidence of pregnant women with congenital and acquired cardiac diseases. Through audits, we aim to prevent future maternal deaths by identifying causes of death and suboptimal factors in the clinical management.

MATERIAL AND METHODS

Maternal deaths in the Nordic countries from 2005 to 2017 were identified through linked registers. The national audit groups performed case assessments based on hospital records, classified the cause of death, and evaluated the standards of clinical care provided. Key messages were prepared to improve treatment.

RESULTS

We identified 227 maternal deaths, giving a maternal mortality rate of 5.98 deaths per 100 000 live births. The most common cause of death was cardiovascular disease (n = 36 deaths). Aortic dissection/rupture, myocardial disease, and ischemic heart disease were the most common diagnoses. In nearly 60% of the cases, the disease was not recognized before death. In more than half of the deaths, substandard care was identified (59%). In 11 deaths (31%), improvements to care that may have made a difference to the outcome were identified.

CONCLUSIONS

Between 2005 and 2017, cardiovascular diseases were the most common causes of maternal deaths in the Nordic countries. There appears to be a clear potential for a further reduction in these maternal deaths. Increased awareness of cardiac symptoms in pregnant women seems warranted.

Natural killer cells and type II interferon in Ro/SSA and La/SSB autoantibody-exposed newborns at risk of congenital heart block

OBJECTIVE

Congenital heart block (CHB) with immune cell infiltration develops in the fetus after exposure to maternal Ro/La autoantibodies. CHB-related serology has been extensively studied, but reports on immune-cell profiles of anti-Ro/La-exposed neonates are lacking. In the current study, we characterised circulating immune-cell populations in anti-Ro/La+mothers and newborns, and explored potential downstream effects of skewed neonatal cell populations.

METHODS

In total, blood from mothers (n=43) and neonates (n=66) was sampled at birth from anti-Ro/La+ (n=36) and control (n=30) pregnancies with or without rheumatic disease and CHB. Flow cytometry, microarrays and ELISA were used for characterising cells and plasma.

RESULTS

Similar to non-pregnant systemic lupus erythematosus and Sjögren-patients, anti-Ro/La+mothers had altered B-cell subset frequencies, relative T-cell lymphopenia and lower natural killer (NK)-cell frequencies. Surprisingly, their anti-Ro/La exposed neonates presented higher frequencies of CD56^dimCD16^hi NK cells (p<0.01), but no other cell frequency differences compared with controls. Type I and II interferon (IFN) gene-signatures were revealed in neonates of anti-Ro/La+ pregnancy, and exposure of fetal cardiomyocytes to type I IFN induced upregulation of several NK-cell chemoattractants and activating ligands. Intracellular flow cytometry revealed IFNγ production by NK cells, CD8⁺ and CD4⁺ T cells in anti-Ro/La exposed neonates. IFNγ was also detectable in their plasma.

CONCLUSION

Our study demonstrates an increased frequency of NK cells in anti-Ro/La exposed neonates, footprints of type I and II IFN and an upregulation of ligands activating NK cells in fetal cardiac cells after type I IFN exposure. These novel observations demonstrate innate immune activation in neonates of anti-Ro/La+pregnancy, which could contribute to the risk of CHB.

Management and outcomes of newborns at risk for inherited antithrombin deficiency

BACKGROUND

As levels of antithrombin (AT) are low at birth, diagnosing inherited AT deficiency in newborns is challenging. In Stockholm, Sweden, pregnant women with known AT deficiency are referred to the Karolinska University Hospital, where local guidelines for management of newborns at risk of inherited AT deficiency have been established. Data on pregnancy, obstetric, and neonatal outcomes are recorded in a registry.

OBJECTIVES

We aimed to evaluate the current practice at the Karolinska University Hospital for managing delivery of newborns at risk for AT deficiency, the predictive value of AT levels at birth, and the neonatal outcomes of newborns with AT deficiency.

PATIENTS/METHODS

This was an observational, retrospective study. All children born to mothers with AT deficiency at the Karolinska University Hospital 2003-2018 were identified from the registry and included in the study. Data were collected from the medical records and the registry. AT activity was measured postnatally and after 6 months of age.

RESULTS

The total study cohort included 41 newborns. There was a significant association between low AT values postnatally and after 6 months of age (P = .001). Half (21/41) of the children were diagnosed with AT deficiency; two suffered from sinus thrombosis, which presented at 10 days of age. Both children with sinus thrombosis were delivered using vacuum extraction.

CONCLUSIONS

The current practice of testing newborns can in most cases predict inherited AT deficiency. The risk for thrombosis during the neonatal period is enhanced by the use of instrumental delivery.

Changes in the plasma microvesicle proteome during the ovarian hyperstimulation phase of assisted reproductive technology

The incidence of pulmonary and venous thromboembolism is increased during the first trimester of pregnancies after assisted reproductive technology (ART) compared to spontaneous conception. We previously found that haemostatic plasma variables changed but within normal limits during controlled ovarian hyperstimulation (COH) concomitant with a major increase in plasma microvesicles (MVs) and markers indicating cell activation. We now explored the proteome of these MVs. Thirty-one women undergoing ART were blood sampled at down-regulation (DR) of oestrogen and at high level stimulation (HLS) with its 10–100-fold increased oestrogen level. Samples were analysed by liquid chromatography and tandem mass spectrometry to identify and quantify the proteome. We identified 306 proteins in the MVs and 72 had changed significantly at HLS compared to DR and more than 20% of them were associated with haemostasis. Thus, proteins related to both haemostasis and complement activation altered in plasma MVs in parallel with MV activation during COH. This needs to be further explored in the clinical context.

[Program for clinical care of immune thrombocytopenic purpura in pregnancy]

A program for care of women with immune thrombocytopenic purpura (ITP) with the recommendation to avoid treatment if platelets were >20 × 109/l during pregnancy, with the target level 100 × 109/l at delivery, was introduced. Treatment should be given with intravenous immunoglobulin (IVIG) or corticosteroids. Out of 75 pregnancies with ITP, 39 percent were treated and the treatment period was shorter with IVIG. Blood loss at delivery was similar as the reference population. Epidural analgesia was given in only 17 percent of the vaginal deliveries. Twenty-three percent of the infants had platelet counts less than 50 × 109/l during the first days after birth. If the women had prior neonatal trombocytopenia 63 percent got a child with thrombocytopenia and 40 percent of those with platelets <20 × 109/l during pregnancy had a child with thrombocytopenia. Multidisciplinary care of pregnant women with ITP including obstetricians, hematologists and neonatologists is recommended.

Obstetric and neonatal outcomes in pregnant women treated with high-dose thromboprophylaxis: a retrospective, single-center study

INTRODUCTION

It is well established that women with very high risk of developing antenatal thrombosis benefit from high-dose thromboprophylaxis, however data on outcomes and the safety and efficacy of thromboprophylaxis are scarce. The aim of the study was to evaluate the safety and effectiveness of the Swedish guidelines for high-dose thromboprophylaxis and the obstetric outcomes in a single-center patient cohort.

PATIENTS AND METHODS

Forty-seven women treated at the Department of Obstetrics and Gynecology, Karolinska University Hospital, Solna, Sweden, between 2004 and 2017 were included in this retrospective study. Data on treatment, obstetric, and neonatal outcomes and medical history were collected. Data derived from the Swedish Medical Birth Registry on women giving birth in Stockholm County 2004-2016 were used as controls. The protocol of the study was approved by the Regional Ethics Committee in Stockholm, Sweden.

RESULTS

The initial thromboprophylaxis dose was 5000 IU dalteparin twice daily. No patient developed ablatio placentae or preeclampsia. One patient suffered antenatal muscle vein thrombosis. Six patients (12.7%) suffered postpartum hemorrhage (PPH); however only one patient had severe PPH. Forty-eight children were born. Three children (6%) were diagnosed with intrauterine growth retardation, five (10%) were born small for gestational age and seven (15%) were born premature, the majority of which (except for two premature) to women with thrombophilia.

DISCUSSION

High-dose thromboprophylaxis was effective and safe. The incidence of preeclampsia and ablatio was lower than in controls; however, neonatal outcomes were worse, especially among mothers with thrombophilia. Due to the diversity of the thrombophilic traits, no thrombophilia-specific conclusion could be drawn. Stricter adherence to the guidelines could further decrease the risk for bleeding, whereas more frequent antenatal controls could possible improve neonatal outcomes.

Obstetric outcomes in patients with primary thrombotic and obstetric antiphospholipid syndrome and its relation to the antiphospholipid antibody profile

Introduction: Previous studies suggested different obstetric outcomes between patients with thrombotic or obstetric antiphospholipid syndrome, but the data are inconclusive. Aims: To investigate obstetric outcomes and their relation to the antiphospholipid antibody profile in primary thrombotic or obstetric antiphospholipid syndrome patients and compare those to a control population. Materials and methods: A retrospective single-centre study on a cohort of 30 pregnant women with primary antiphospholipid syndrome treated at Karolinska University Hospital Solna, Sweden between 2000 and 2016. The pregnancy outcomes were compared to the outcomes of all pregnancies in Stockholm County during the same period. Results: Preeclampsia ( p < 0.001), low birth weight at delivery ( p = 0.001), Apgar < 7 at 5 minutes ( p < 0.001) and small infants ( p < 0.001) were more common in antiphospholipid syndrome patients compared to controls. Obstetric antiphospholipid syndrome patients had a higher incidence of small infants ( p = 0.023), lower birth weight ( p = 0.013) and infants born with complications ( p=0.004) compared to thrombotic antiphospholipid syndrome. Mothers with triple antibody positivity had a higher incidence of preeclampsia ( p = 0.03), preterm delivery ( p = 0.011), small infants ( p=0.002) and infants born with complications ( p = 0.012). Conclusions: Patients with primary antiphospholipid syndrome, especially those with obstetric antiphospholipid syndrome and triple antibody positivity, are at higher risk for adverse pregnancy outcomes, even under antithrombotic treatment. More frequent antenatal controls in high-risk patients can further improve outcomes.

Blood inflammatory and endothelial markers in women with von Willebrand disease

Introduction

VWD-affected females often experience menorrhagia. Periodical fluctuations of the sex steroids during the menstrual cycle cause changes both in the coagulation and immune system. The aim of the current study was to assess the changes in selected inflammatory and endothelial markers in women with VWD during two phases of the menstrual cycle (follicular and luteal) and to compare it with corresponding data from healthy controls.

Materials and methods

The study group included 12 VWD-affected females with regular menstrual cycle, with none of them being prescribed hormone treatment. They were not pregnant or breastfeeding. The control group consisted of 102 healthy females, matched for age and BMI.

Results

Within the VWD group, endostatin was higher during the follicular phase, compared to the luteal phase, although the difference was not significant (p = 0.062). sICAM-1 and IL-6 were higher in VWD-affected females, compared to the controls, sVCAM-1, cathepsin S and sP-selectin were lower (p<0.003 for all cases). The pattern was constant throughout the menstrual cycle.

Conclusions

Higher levels of endostatin during early follicular phase could potentially predispose women with VWD to the development of heavy menstrual bleeding, due to antiangiogenic properties and ability to suppress several coagulation factors. Lower p-selectin levels in VWD group, compared to controls, may also contribute to the bleeding tendency. Changes in other proteins, involved in angiogenesis are hypothetically related to the formation of angiodysplasia—common complication of VWF deficiency. The latter statement requires confirmation in larger studies.

Thrombin generation during a regular menstrual cycle in women with von Willebrand disease

Fluctuations of the sex steroids during the menstrual cycle might significantly influence hemostasis. This association, derived from a number of the observations on healthy women, is yet to be described in females affected by bleeding disorders. The aim of the current study was to assess the changes in hemostatic variables in women with vWD during two phases of the menstrual cycle (follicular and luteal) and to compare it with healthy controls. The study group included 12 vWD-affected females with regular menstrual cycle, with none of them being prescribed any hormonal treatment. The control group consisted of 102 healthy females, matched for age and BMI. Within the vWD group FVIII and FX were both significantly higher during follicular phase than in luteal phase (p = 0.013 and p = 0.033 respectively). AT, FII, FVII and FX were higher in women with vWD, compared with controls during both phases of the menstrual cycle (p < 0.0005, p < 0.0005, p = 0.001 and p < 0.0005). In women with vWD, lag time and time to peak were prolonged during both phases of the menstrual cycle(p < 0.0005), while peak thrombin concentration was reduced (p = 0.003 and p = 0.002 during follicular and luteal phase respectively) compared to healthy peers. Lower levels of FVIII and FX during luteal phase may predispose women to the development of the menorrhagia - common complication of vWD. Women with vWD need more time to reach the peak thrombin concentration, while the latter still remains less than in healthy women. Higher levels of AT in vWD-affected females, compared to controls, may also contribute to the existing bleeding tendency in this cohort.

Obstetric antiphospholipid syndrome

The present clinical and laboratory classification criteria for antiphospholipid syndrome (APS) were established in Sydney, Australia, in 2006. In this review, we focus on the obstetric subset of APS (OAPS), defined by persistent positivity for antiphospholipid antibodies together with either early recurrent pregnancy loss, early fetal death, stillbirth or premature birth <34 gestational weeks due to pre-eclampsia, eclampsia and placental insufficiency. It is important to diagnose these cases since most women suffering from OAPS can, when given appropriate treatment, have successful pregnancies. Furthermore, patients with OAPS may, depending on the antibody profile, be at enhanced risk of thrombotic events later in life. We present an update on the present knowledge of possible underlying pathogenesis, risk factors and risk estimations for adverse pregnancy outcomes before and during pregnancy, current treatment concepts, and long-term outcomes for women with OAPS and their children.

Prediction of Changes in Levels of Haemostatic Variables during Natural Menstrual Cycle and Ovarian Hyperstimulation

To find if there is a relation between levels of haemostatic variables at low and high hormonal levels (oestradiol and progesterone) in an individual, blood samples were drawn from 12 women repeatedly during one menstrual cycle (Study I) and from 14 women undergoing in vitro fertilization, before hormonal stimulation and daily during the periovu- latory period (Study II). Regression coefficients were calculated between minimum (independent) and maximum (dependent) values in both studies. In Study II highly significant regression coefficients were found between oestradiol minimum (pretreatment) and maximum (mcdian 105 and 4730 pmol/1, respectively) for coagulation factors FVIII, von Willebrand Factor (antigen), FVII (activity and antigen), fibrinogen, protein C, protein S (free), antithrombin, plasminogen and plasminogen activator inhibitor-1; furthermore, between progesterone-minimum at day -3 or -2 (related to ovum pick up) and maximum (median 4.7 and 98 nmol/1, respectively) for FVIII, von Willebrand Factor, FVII (activity and antigen), protein C, protein S (free), and plasminogen. In Study I, where much lower hormonal levels were obtained at maximum (oestradiol median 297 pmol/1 and and progesterone 47 nmol/1), the same pattern was observed especially for FVIII, FX, fibrinogen, plasminogen and plasmin inhibitor. Thus, the concentration of a haemostatic variable at a low oestradiol or progesterone level can predict the level at a high hormonal level.

Pregnancy-associated plasma protein-A is positively correlated with first-trimester skin microvascular reactivity

OBJECTIVE

To investigate the relationship between levels of circulating maternal pregnancy-associated plasma protein-A (PAPP-A) and first-trimester maternal vascular function.

METHODS

This was a cross-sectional study of 53 healthy, non-smoking, nulliparous pregnant women in Stockholm, Sweden. PAPP-A levels and vascular function were assessed during gestational weeks 11-14. Forearm skin microcirculation was investigated by laser Doppler perfusion imaging during iontophoresis of acetylcholine (ACh) and sodium nitroprusside (SNP) to assess endothelium-dependent and -independent microvascular vasodilatation, respectively. Microvascular endothelial function index was calculated as peak ACh/peak SNP. Endothelium-dependent and -independent vasodilatation in the brachial artery was evaluated, respectively, by postischemic hyperemia-induced flow-mediated vasodilatation (FMD) and by response to sublingual intake of glyceryl trinitrate (GTN).

RESULTS

PAPP-A was correlated with skin microvascular endothelial function index (β = 1.008 (95% CI, 0.34-1.68), r²  = 0.17, P = 0.004). PAPP-A also correlated inversely with FMD (β = -0.052 (95% CI, -0.094 to -0.011), r²  = 0.13, P = 0.014) but did not relate to forearm endothelial function index (i.e. FMD/GTN). The results were retained in multivariate analyses including known confounding factors.

CONCLUSIONS

First-trimester endothelium-dependent skin microvascular reactivity was positively related to PAPP-A levels. If confirmed, these novel findings suggest that first-trimester skin microvascular reactivity could be a useful early pregnancy marker of placental function. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

Does Thrombin Activatable Fibrinolysis Inhibitor (TAFI) Contribute to Impairment of Fibrinolysis in Patients with Preeclampsia and/or Intrauterine Fetal Growth Retardation?

Thrombin Activatable Fibrinolysis Inhibitor (TAFI) is a relatively recently described glycoprotein (MM 55 KDa) that can be converted into its active form by the thrombin/thrombomodulin complex and potentially inhibits fibrinolysis. Since it represents a link between coagulation and fibrinolysis, TAFI can be expected to play a part in various clinical conditions associated with a thrombotic tendency. Preeclampsia (PE) and intrauterine fetal growth retardation (IUFGR) are fairly common complications of pregnancy that are characterized by hemostatic abnormalities. TAFI antigen and its influence on hemostasis was investigated in 46 women with PE and/or IUFGR and in 16 normal pregnancies. We found a significant decrease of TAFI antigen in the patient group. Using the recently described method Overall Hemostatic Potential (OHP) in plasma, we measured clot lysis time (CLT) and overall fibrinolytic potential (OFP). We found that CLT is prolonged and OFP decreased in patients with PE and/or IUFGR. Since OFP did not increase after addition of the specific inhibitor of TAFI (potato tuber carboxypeptidase inhibitor), it seems that TAFI does not contribute to the impairment of fibrinolysis in these patients. Since serum albumin was decreased together with presence of proteinuria and aminotransferases were increased in the patients, it seems that one explanation for the decrease in TAFI could be reduced hepatic synthesis and an increased loss in urine. It can be speculated that this mechanism can prevent more serious thrombotic complications in patients with PE and/or IUFGR.

Haemostatic, Endothelial and Lipoprotein Parameters and Blood Pressure Levels in Women with a History of Preeclampsia

To determine whether perturbations of haemostatic function and lipoprotein metabolism prevail long after preeclampsia and increase the risk of future coronary heart disease (CHD), we conducted a follow-up study in women with (cases, n = 25) or without (controls, n = 24) a history of preeclampsia. Blood samples were taken in the follicular and in the luteal phases of a menstrual cycle. Levels of blood pressure (BP) and proteinuria measured during the index pregnancy were included in the evaluation. Compared to control women who had undergone a normal pregnancy, the formerly preeclamptic patients had higher systolic (p <0.01) and diastolic (p <0.05) BPs and increased plasma levels of von Willebrand factor (vWF), fibrinogen, cholesterol, triglycerides and very low density lipoprotein (VLDL) (all p <0.05). The lipid, vWF, and fibrinogen levels were positively related to the degree of BP elevation but not to the degree of proteinuria during the index pregnancy. Except for the increase in vWF level, all biochemical perturbations were only present in the luteal but not in the follicular phase samples. In conclusion, persistent endothelial dysfunction with ensuing dysregulation of blood pressure, haemostatic perturbation and dyslipoproteinemia after preeclampsia may indicate a proneness to future CHD.

APC resistance during the normal menstrual cycle

Increased serum levels of endogenous as well as exogenous estrogen are regarded to be responsible for acquired activated protein C (APC) resistance. It was the objective of this study to evaluate whether the physiological increase in serum estradiol concentration during the normal menstrual cycle affects the individual’s sensitivity to APC. Seventy-two women with normal menstrual cycles were included in the study. Blood samples for analysis of estradiol (E2), progesterone (P4) and APC resistance were drawn at two time points of the menstrual cycle (day 3–5 and day 22–25). Two methods of measuring APC resistance were used: the activated partial thromboplastin time (aPTT)-based assay and the endogenous thrombin potential (ETP)-based APC resistance test. Independent of the method used, no changes in APC resistance were found, even though the E2 concentration increased significantly between the two menstrual phases. No correlations between E2 levels and APC resistance, P4 levels and APC resistance or changes in E2 concentrations and changes in APC resistance were detected. Ten women were carriers of the factor VLeiden mutation. Their baseline APC resistance was increased, but their response to elevated E2 during the menstrual cycle did not differ from that of non-carriers. In conclusion, our observations suggest that physiological differences in serum levels of estradiol and progesterone between the early follicular and the luteal phase in a normal menstrual cycle do not have any significant impact on the individual’s sensitivity to APC.

Rapid activation of haemostasis after hormonal emergency contraception

Hormonal emergency contraception (EC) is a well established contraceptive method, recommended to all women, although the effects on haemostais are not fully evaluated. The aim of this study was to evaluate whether exposure to EC has effects on well established cardiovascular risk factors, and also to examine whether differences exist between two EC treatments. In a prospective randomized cross over design 11 women used two different EC methods, one with estrogen and levonorgestrel (EE-EC) and one with levonorgestrel only (LNG-EC). Plasma concentrations of haemostatic factors (APC resistance, antithrombin, fibrinogen, prothrombin fragment 1+2, free protein S, factor VII and PAI-1), sex-hormone-binding globulin (SHBG), the apolipoprotein (apo)B/apoA1 ratio and C-reactive protein (CRP) were followed frequently during the following 48 h A rapid haemostatic activation was induced with both treatments, although more pronounced with EE-EC. Already two hours after EC, the plasma concentrations of haemostatic parameters and SHBG were significantly different from baseline concentrations. An ETP-based APC-resistance method showed increased APC resistance with EE-EC and decreased APC resistance with LNG-EC. The ApoB/ApoA1 ratio was affected in a favourable direction with EE-EC.CRP increased slightly regardless of treatment. Even a very short exposure to exogenous sex hormones causes prompt effects on hepatic protein synthesis and the coagulation system. This must be taken into consideration whenever exogenous steroid hormones are administered, especially to individuals with a genetic predisposition to thrombosis or transiently disturbed haemostasis.

Thrombin generation and activated protein C resistance in the absence of factor V Leiden correlates with the risk of recurrent venous thromboembolism in women aged 18–65 years

Identification of patients at high risk of recurrence after a first event of venous thromboembolism (VTE) remains difficult. Resistance to activated protein C (APC) is a known risk factor for VTE, but data on the risk of recurrence is controversial. We wanted to investigate whether APC resistance in the absence of factor V Leiden, determined with global coagulation test such as the thrombin generation assay, could be used as a marker for increased risk of recurrent VTE among women 18–65 years old after a first event of VTE. In a cohort of 243 women with a first event of VTE, plasma was collected after discontinuation of anticoagulant treatment and the patients were followed up for 46 months (median). Thrombin generation was measured via calibrated automated thrombography, at 1 pM and 10 pM of tissue factor (TF). In women without factor V Leiden (n=117), samples were analysed in the absence and in the presence of APC. Increase in ETP (endogenous thrombin potential) and peak height analysed in the presence of APC correlated significantly with higher risk of recurrence. At 1 pM, peak height correlated with increased risk of recurrence. In conclusion, high thrombin generation in the presence of APC, in women after a first event of VTE is indicative for an increased risk of a recurrence. We also found that thrombin generation at low TF (1 pM) is correlated with the risk of recurrence. Our data suggest that APC resistance in the absence of factor V Leiden is a risk factor for recurrent VTE.

Correction: Postpartum Hemorrhage in Women with Von Willebrand Disease - A Retrospective Observational Study

[This corrects the article DOI: 10.1371/journal.pone.0164683.].

Longitudinal study of vascular structure and function during normal pregnancy

OBJECTIVE

To examine alterations in maternal vascular structure and function during normal pregnancy.

METHODS

We assessed brachial and central blood pressure, pulse-wave velocity and augmentation index (by pulse-wave analysis and applanation tonometry), common carotid artery structure (by ultrasonography) and endothelial function in the brachial artery (by postischemic hyperemia-induced flow-mediated vasodilatation by glyceryl trinitrate) and in the forearm skin microcirculation (by laser Doppler perfusion imaging during iontophoretic administration of acetylcholine and sodium nitroprusside) in 52 healthy nulliparous women at 14, 24 and 34 weeks' gestation, and at 9 months postpartum.

RESULTS

During pregnancy, brachial and central systolic and diastolic blood pressures initially decreased but subsequently increased (all P < 0.05). Flow-mediated vasodilatation in the brachial artery increased during early pregnancy (P < 0.05), whereas non-specific vasodilatation by glyceryl trinitrate decreased (P < 0.01), indicating improved endothelial function. Thus, endothelial function index (forearm blood flow/glyceryl trinitrate) increased during pregnancy (0.30 ± 0.18 in the non-pregnant state at 9 months postpartum and 0.51 ± 0.19, 0.61 ± 0.39 and 0.49 ± 0.30 in the first, second and third trimesters, respectively) (P < 0.001). Endothelium-dependent skin microvascular reactivity to acetylcholine also increased (P < 0.01). Carotid-femoral pulse-wave velocity decreased during pregnancy (5.88 ± 0.91 m/s in the non-pregnant state and 5.55 ± 0.67, 5.12 ± 0.66 and 5.62 ± 0.74 m/s in the first, second and third trimesters, respectively) (P < 0.001).

CONCLUSION

During normal pregnancy, the blood volume expansion necessary for sufficient fetal growth is accommodated by early and marked changes in the matvascular system. This seems to be dependent on normal adaptive endothelial and vascular function. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.

Fetal growth is associated with first-trimester maternal vascular function

OBJECTIVE

To investigate the relationship between maternal endothelial function in the first trimester, assessed in both the brachial artery and the forearm skin microcirculation, and fetal growth.

METHODS

Vascular function was assessed in 56 pregnant women during gestational weeks 11-14. Vascular reactivity in the brachial artery was evaluated by postischemic hyperemia-induced flow-mediated vasodilatation (FMD) and by vasodilatation following administration of sublingual glyceryl trinitrate (GTN). Forearm skin microcirculation was investigated by laser Doppler perfusion imaging during iontophoresis of acetylcholine (ACh) and sodium nitroprusside (SNP) to assess endothelium-dependent and -independent microvascular vasodilatation, respectively. Fetal growth was measured at study inclusion and birth-weight centile was calculated after delivery.

RESULTS

FMD and GTN-induced vasodilatation were both associated with birth-weight centile. On multivariate analysis (adjusted for brachial artery diameter at rest, blood pressure, maternal age and heart rate), for FMD β = 1.7 (95% CI, 0.06-3.34), r²  = 0.26 and P = 0.042, and for GTN-induced vasodilatation β = 2.6 (95% CI, 0.44-4.68), r²  = 0.15 and P = 0.02. Endothelium-dependent and -independent microvascular reactivity were also associated with birth-weight centile: for ACh β = 7.82 (95% CI, 1.81-13.83), r²  = 0.12 and P = 0.029, and for SNP β = 6.27 (95% CI, 1.20-11.34), r²  = 0.11 and P = 0.016.

CONCLUSION

First-trimester maternal vascular dilatation capacity (rather than endothelial function alone) is associated with fetal growth. These findings were consistent in both the brachial artery and the forearm skin microcirculation. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.

Late Results after Thrombectomy for Ilio-Femoral Venous Thrombosis

Sixty-three of 68 patients who underwent thrombectomy with a temporary arteriovenous fistula for ilio-femoral venous thrombosis were followed-up after a mean time of 66 months (range 15–130). Fifty-four were women with a mean age of 29 years (range 13–66). A primary successful operation was performed in 54 patients (86%); at 16 months 34 (54%) were judged to have a patent ilac vein. At long-term follow-up 23 patients had no symptoms, 17 had leg swelling, venous claudication and/or present or previous ulcer while 23 had leg swelling only. Fourteen (22%) had noticed a decreased capacity to perform their job and 21 (33%) had to compensate daily for the discomfort of the diseased leg. Recurrent thrombotic disease occurred in eight patients and did not seem to be associated with symptoms at follow-up. The results of the operated patients seem to be favourable compared to other reports of conservative treatment, especially for fertile women and with a reduced risk of future venous insufficiency. In young patients with a long life expectancy this is particularly important.

Heavy menstrual bleeding and health-associated quality of life in women with von Willebrand's disease

Women with the inherited bleeding disorder von Willebrand's disease (VWD) face gender-specific hemostatic challenges during menstruation. Heavy menstrual bleeding (HMB) can negatively affect their overall life activities and the health-associated quality of life. The purpose of the present study was to investigate whether women with VWD experienced HMB and an impaired health-associated quality of life. The study subjects were recruited from the Coagulation Unit of Karolinska University Hospital. Information was retrieved from various self-administered forms and medical records. Of the 30 women (18-52 years) that were included in the present study, 50% suffered from HMB, although the majority received treatment for HMB. In addition, almost all the included women perceived limitations in the overall life activities due to menstruation. The health-associated quality of life for women with HMB was significantly lower (P<0.10) with regards to 'bodily pain' compared with Swedish women of the general population. In conclusion, women with VWD experienced reduced health-associated quality of life as a result of HMB. Therefore, preventing limitations in overall life activities and improving their health-associated quality of life thorough counseling on menstrual bleeding is important for women with VWD.

Inflammatory and endothelial markers during the menstrual cycle

BACKGROUND

The menstrual cycle exhibits a pattern of repeated inflammatory activity. The present study aims to evaluate inflammatory and endothelial markers during the two phases of a menstrual cycle.

METHODS

The study cohort consisted of 102 women with regular menstrual cycles. Inflammatory and endothelial markers (interleukin-6 [IL-6], pentraxin-3 [PTX-3], hs-C reactive protein [hs-CRP], sE-selectin, sP-selectin, intracellular and vascular cell adhesion molecules [ICAM-1 and VCAM-1] and cathepsins L, B and S) were measured during the early follicular and the late luteal phase of a normal menstrual cycle.

RESULTS

Pentraxin-3 (PTX-3) and hs-CRP were significantly higher during the follicular phase compared to the luteal phase (p < 0.001 respectively p = 0.025). The other inflammatory and endothelial markers, with the exception of cathepsin B, were higher, albeit not significantly, during the follicular phase.

CONCLUSIONS

Inflammatory activity, expressed mainly by members of the pentraxin family, is higher during the early follicular compared to the luteal phase. This could be associated to menstruation but the exact mechanisms behind this pattern are unclear and might involve the ovarian hormones or an effect on hepatocytes.

The efficacy of hydroxychloroquine for obstetrical outcome in anti-phospholipid syndrome: Data from a European multicenter retrospective study

In European multicenter study, we aimed to describe the real-life hydroxychloroquine use in APS patients during pregnancy and determine its benefit in refractory obstetrical APS. We analyzed the outcome of pregnancies treated by hydroxychloroquine in patients with APS or asymptomatic antiphospholipid (aPL) antibodies carriers. Thirty patients with APS with 35 pregnancies treated by hydroxychloroquine were analyzed. Comparing the outcome of pregnancies treated by the addition of hydroxychloroquine to previous pregnancies under the conventional treatment, pregnancy losses decreased from 81% to 19% (p<0.05), without differences in the associated treatments. The univariate analysis showed that the previous intrauterine deaths and higher hydroxychloroquine amount (400mg per day) were the factors associated with pregnancy outcome. Considering 14 patients with previous refractory obstetrical APS (n=5 with obstetrical and thrombotic primary APS and n=9 with purely obstetrical APS), all with previous pregnancy losses under treatment (aspirin with LMWH in 11 cases and LMWH in 3 cases), the addition of hydroxychloroquine resulted in live born babies in 11/14 (78%) cases (p<0.05). Our study shows the benefit of hydroxychloroquine addition in patients with refractory obstetrical APS and raises the need of prospective studies to confirm our preliminary study.

Association between trefoil factor 3 gene variants and idiopathic recurrent spontaneous abortion

Trefoil factor 3 (TFF3) gene is an inflammatory mediator expressed in human endometrium during the window of implantation. The aim of this study was to evaluate the possible genetic association of TFF3 variants in recurrent spontaneous abortion. Women with a history of recurrent spontaneous abortion (n = 164) and healthy pregnant women (n = 143) were genotyped for five TFF3 polymorphisms (rs225439 G/A, rs533093 C/T, rs225361 A/G, rs11701143 T/C and rs77436142 G/C). In addition, haplotypes formed within the gene were analysed. Within the recurrent spontaneous abortion group, women who at some point had given birth and childless women had 4.19 ± 1.75 and 5.34 ± 3.42 consecutive spontaneous abortions, respectively. Women who had experience recurrent spontaneous abortions had a lower allele frequency of the rs11701143 promoter region minor C allele compared with fertile women (0.02 versus 0.05, P = 0.015). Patients with rs225361 AG genotype had significantly more successful pregnancies before spontaneous abortion than those with homozygous AA and GG genotypes (P = 0.014). No significant differences in haplotype frequencies between patients and controls were detected. Possible genetic risk factors identified that might contribute to the pathogenesis of idiopathic recurrent spontaneous abortion were TFF3 gene variants.

The histidine-rich glycoprotein A1042G polymorphism and recurrent miscarriage: a pilot study

BACKGROUND

Histidine-rich glycoprotein (HRG) has previously been shown to have an impact on implantation and fertility. The aim of this study was to investigate if there is an association between the HRG A1042G single nucleotide polymorphism (SNP) and recurrent miscarriage.

METHODS

The study was designed as a case-control study and the women were included at University Hospitals in Sweden. 186 cases with recurrent miscarriage were compared with 380 pregnant controls with no history of miscarriage. Each woman was genotyped for the HRG A1042G SNP.

RESULTS

The results indicated that the frequency of heterozygous HRG A1042G carriers was higher among controls compared to cases (34.7% vs 26.3%; p<0.05). In a bivariate regression analysis, a negative association was found between recurrent miscarriage and heterozygous A/G carriers both in the entire study population (OR 0.67, 95% CI 0.45 - 0.99; p<0.05) as well as in a subgroup of women with primary recurrent miscarriage (OR 0.37, 95% CI 0.16 - 0.84; p<0.05). These results remained even after adjustment for known confounders such as age, BMI and thyroid disease (OR 0.36, 95% CI 0.15 - 0.84; p<0.05).

CONCLUSIONS

Women who are heterozygous carriers of the HRG A1042G SNP suffer from recurrent miscarriage more seldom than homozygous carriers. Thus, analysis of the HRG A1042G SNP might be of importance for individual counseling regarding miscarriage.

Treatment strategies and pregnancy outcomes in antiphospholipid syndrome patients with thrombosis and triple antiphospholipid positivity. A European multicentre retrospective study

Previous thrombosis, diagnosis of systemic lupus erythematosus (SLE) and triple antiphospholipid (aPL) antibody positivity have recently been found to be independent factors associated to pregnancy failure during conventional therapy in women with antiphospholipid syndrome (APS). This study aimed to assess the effect of various treatment strategies on pregnancy outcomes in women with APS and the risk factors for pregnancy failure. One hundred ninety-six pregnancies of 156 patients diagnosed with APS were analysed: 118 (60.2%) of these had previous thrombosis, 81 (41.3%) were diagnosed with SLE, and 107 (54.6%) had triple aPL positivity. One hundred seventy-five (89.3%) were treated with conventional therapies (low-dose aspirin [LDA] or prophylactic doses of heparin + LDA or therapeutic doses of heparin + LDA), while 21 (10.7%) were prescribed other treatments in addition to conventional therapy. The pregnancies were classified into seven risk profiles depending on the patients' risk factors - thrombosis, SLE, and triple aPL positivity - and their single, double or triple combinations. It was possible to find significant difference in outcomes correlated to treatments only in the thrombosis plus triple aPL positivity subset, and logistic regression analysis showed that additional treatments were the only independent factor associated to a favourable pregnancy outcome (odds ratio=9.7, 95% confidence interval=1.1-88.9, p-value<0.05). On the basis of this retrospective study, we found that APS pregnant patients with thrombosis and triple aPL positivity treated with additional therapy had a significant higher live-birth rate with respect to those receiving conventional therapy alone.

Pre-eclampsia affects cord blood NK cell expression of activation receptors and serum cytokine levels but not CB monocyte characteristics

PROBLEM

Maternal immunopathology in pre-eclampsia is well studied; however, less is known regarding the immunological effects on the newborns. Increased inflammation and activation of immune cells at the fetal-maternal interface in pre-eclampsia could influence the neonatal immune compartment.

METHOD OF STUDY

Monocytes and natural killer (NK) cells from cord blood (CB) of children with pre-eclamptic or healthy mothers were analyzed by flow cytometry for surface markers and intracellular cytokines. In addition, serum cytokine profiles were investigated using ELISA or cytometric bead array.

RESULTS

Neonates born to pre-eclamptic mothers had an inflammatory serum cytokine profile. While CB monocyte characteristics seemed unaffected, CB NK cells from pre-eclamptic pregnancies had higher NKp30, but borderline lower NKG2D expression.

CONCLUSION

In utero inflammatory priming of neonatal innate immunity taking place in pre-eclamptic pregnancies might influence specific NK cell functions in newborns.

Histidine-rich glycoprotein gene polymorphism in patients with recurrent miscarriage

Association between the histidine-rich glycoprotein (HRG) C633T single nucleotide polymorphism (SNP) and recurrent miscarriage was investigated in a case-control study. The cases constituted 187 women with recurrent miscarriage that were compared with 395 controls who had delivered a child and had no history of miscarriage. Blood samples were collected from each woman, genomic DNA was extracted and genotyped for the HRG C633T SNP. In the whole study population, the percentage of miscarriage was the same, regardless of genotype (C/C 31.2%, C/T 32.9% and T/T 32.5%). However, an association between homozygous T/T carriers and recurrent miscarriage was detected in a subgroup of women with primary recurrent miscarriage (odds ratio 2.44, 95% CI 1.01-5.92). Our results indicate an important role for the HRG C633T SNP in the occurrence of recurrent miscarriage.

Endogenous thrombin potential is higher during the luteal phase than during the follicular phase of a normal menstrual cycle

STUDY QUESTION

Do thrombin generation and haemostatic parameters differ during the two phases of the menstrual cycle?

SUMMARY ANSWER

Total thrombin concentration is higher during the luteal phase compared with the follicular phase of the menstrual cycle.

WHAT IS KNOWN ALREADY

The coagulation cascade is affected by many variables, such as fluctuations in the levels of sex hormones. The studies on the variations in haemostatic parameters during the menstrual cycle have produced diverse results.

STUDY DESIGN, SIZE, DURATION

Thrombin generation and selected haemostatic parameters (fibrinogen, factor II, factor VII, factor VIII, factor X, von Willebrand factor, antithrombin and D-dimer) were measured during the two phases of a normal menstrual cycle in 102 healthy women not taking any form of hormone medication.

PARTICIPANTS/MATERIALS, SETTING, METHODS

The study cohort consisted of 102 healthy women with regular menstrual cycles. Thrombin generation was measured by the calibrated automated thrombogram method. Progesterone and sex hormone-binding globulin were measured by chemiluminescence enzyme immunoassays. Estradiol was measured by a sensitive radioimmunoassay. Fibrinogen was measured by a clotting method, antithrombin was measured by a chromogenic method and factor II, factor VII, factor VIII, factor X, von Willebrand factor and D-dimer were measured by photometric methods.

MAIN RESULTS AND THE ROLE OF CHANCE

It was shown that the total amount of generated thrombin (Endogenous Thrombin Potential) was significantly higher during the luteal compared with the follicular phase (P = 0.027). Factor X was significantly higher during the follicular phase (P = 0.028). Progesterone exhibited significant associations (measured by the least squares regression analysis) with fibrinogen and factor X during the follicular phase (P = 0.043 and P = 0.033, respectively) and with factors II and VII during the luteal phase (P = 0.034 and P = 0.024, respectively). The validity of the results from the regression analysis was further confirmed by performing correlation analyses (Pearson correlation matrix) for haemostatic markers for the luteal and follicular phases (accepted correlation level >0.8).

LIMITATIONS, REASONS FOR CAUTION

The wide confidence interval for the differences in endogenous thrombin potential during the two phases could imply that the size of the cohort may not be sufficient to fully evaluate the biological variations. Additionally, the haemostatic markers were not shown to have significant associations with thrombin generation, suggesting that the increased thrombin concentration during the luteal phase would be mediated by another mechanism, as yet unidentified.

WIDER IMPLICATIONS OF THE FINDINGS

The associations between progesterone and the haemostatic markers, as shown for both phases of the menstrual cycle, suggest a previously unknown or undefined yet potentially significant role for progesterone in the coagulation system. However, it has been shown that the use of progestogen-only preparations does not affect the coagulation system, which is partly the reason why they are considered safe for women with thrombophilia or previous thrombotic event. Further studies are required in order to demonstrate whether our results can be extrapolated for synthetic progestins, which might have significant implication on the indications for their use.

Phosphodiesterase 8B gene polymorphism in women with recurrent miscarriage: a retrospective case control study

Background

Recurrent miscarriage affects approximately 1% of all couples. There is a known relation between hypothyroidism and recurrent miscarriage. Phosphodiesterase 8B (PDE8B) is a regulator of cyclic adenosine monophosphate (cAMP) with important influence on human thyroid metabolism. Single nucleotide polymorphism (SNP) rs 4704397 in the PDE8B gene has been shown to be associated with variations in serum Thyroid Stimulating Hormone (TSH) and thyroxine (T4) levels. The aim of this study was to investigate whether there is an association between the SNP rs 4704397 in the PDE8B gene and recurrent miscarriage.

Methods

The study was designed as a retrospective case control study. 188 cases with recurrent miscarriage were included and compared with 391 controls who had delivered at least once and with no history of miscarriage or assisted reproduction.

Results

No difference between cases and controls concerning age was found. Bivariate associations between homozygous A/A (OR 1.57, 95% CI 0.98-2.52) as well as G/G carriers (OR 1.52, 95% CI 1.02-2.25) of SNP rs 4704397 in PDE8B and recurrent miscarriage were verified (test for trend across all 3 genotypes, p = 0.059). After adjustment for known confounders such as age, BMI and smoking the association between homozygous A/A (AOR 1.63, 95% CI 1.01 - 2.64, p = 0.045) and G/G (AOR 1.52, 95% CI 1.02 - 2.27, p = 0.039) carriers of SNP rs 4704397 in PDE8B and recurrent miscarriage remained.

Conclusions

Our findings suggest that there is an association between homozygous A/A as well as homozygous G/G carriers of SNP rs 4704397 in PDE8B and recurrent miscarriage.

Studies of microparticles in patients with the antiphospholipid syndrome (APS)

OBJECTIVES

To study circulating platelet, monocyte and endothelial microparticles (PMPs, MMPs and EMPs) in patients with antiphospholipid syndrome (APS) in comparison with healthy controls.

MATERIAL AND METHOD

Fifty-two patients with APS and 52 healthy controls were investigated. MPs were measured on a flow cytometer (Beckman Gallios) and defined as particles sized < 1.0 µm, negative to phalloidin, positive to lactadherin and positive to either CD42a (PMPs), CD144 (EMPs) or CD14 (MMPs). Exposure of CD142 (TF) was measured on CD144 positive MPs.

RESULTS

Total number of MPs (i.e. lactadherin positive particles) was higher in APS patients versus controls (p < 0.001). An increased number of EMPs (p < 0.001), increased TF-positive EMPs (p < 0.001) and increased MMPs (p < 0.001) were also observed. PMP numbers did not differ between the groups. None of the MP types differed in numbers between obstetric and thrombotic APS patients.

CONCLUSION

We observed a high number of EMPs expressing TF in APS patients. The numbers of MMPs and total EMPs were also higher as compared with healthy controls but in contrast to previous reports, the number of PMPs did not differ between groups.

Efficacy of obstetric thromboprophylaxis and long-term risk of recurrence of venous thromboembolism

OBJECTIVE

To study the efficacy of thromboprophylaxis with low molecular weight heparin (LMWH) in pregnant women with one previous venous thromboembolic event (VTE). Secondary aims were to study the long-term risk of secondary recurrence, bleeding and obstetric complications.

DESIGN

A prospective national study of long-term LMWH thromboprophylaxis in Sweden.

SETTINGS

All hospitals in Sweden during January 1998-December 2002,

PARTICIPANTS

Pregnant women with one previous VTE and controls drawn from the Swedish Medical Birth Registry. The women were cross-matched with the Swedish Hospital Discharge Register to identify all recurrences and to ascertain the annual risk of recurrence.

MAIN OUTCOME MEASURES

Recurrence of VTE, bleeding complications at delivery and obstetric complications.

RESULTS

326 of 393 registered women could be evaluated. The relative risk reduction in VTE was 88%. There was an absolute increased risk of VTE during the thromboprophylaxis period: 1.2% compared to 0.2% among controls (p<0.001). The risk during the immediate post-treatment period (43-100 days post-partum) was increased 28-fold. The annual incidence of VTE after delivery was 1%. The risk of hematoma and major blood loss at delivery was increased during thromboprophylaxis (p<0.001). There were no differences in the incidences of preeclampsia, intrauterine growth restriction or placental abruption.

CONCLUSIONS

The relative risk reduction in VTE during thromboprophylaxis was 88%. After pregnancy, the annual long-term risk of recurrence was 1%. The risk was most pronounced in the post-treatment period. There was an increased risk of bleeding complications among women given LMWH, but there was no effect on obstetric complications.