Platelet-derived factors dysregulate placental sphingosine-1-phosphate receptor 2 in human trophoblasts.

RESEARCH QUESTION: Sphingosine-1-phosphate (S1P) is an essential and bioactive sphingolipid with various functions, which acts through five different G-protein-coupled receptors (S1PR1-5). What is the localization of S1PR1-S1PR3 in the human placenta and what is the effect of different flow rates, various oxygen concentrations and platelet-derived factors on the expression profile of S1PR in trophoblasts? DESIGN: Expression dynamics of placental S1PR1-S1PR3 were determined in human first trimester (n = 10), pre-term (n = 9) and term (n = 10) cases. Furthermore, the study investigated the expression of these receptors in different primary cell types isolated from human placenta, verified the findings with publicly available single-cell RNA-Seq data from first trimester and immunostaining of human first trimester and term placentas. The study also tested whether the placental S1PR subtypes are dysregulated in differentiated BeWo cells under different flow rates, different oxygen concentrations or in the presence of platelet-derived factors. RESULTS: Quantitative polymerase chain reaction revealed that S1PR2 is the predominant placental S1PR in the first trimester and reduces towards term (P < 0.0001). S1PR1 and S1PR3 increased from first trimester towards term (P < 0.0001). S1PR1 was localized in endothelial cells, whereas S1PR2 and S1PR3 were predominantly found in villous trophoblasts. Furthermore, S1PR2 was found to be significantly down-regulated in BeWo cells when co-incubated with platelet-derived factors (P = 0.0055). CONCLUSION: This study suggests that the placental S1PR repertoire is differentially expressed across gestation. S1PR2 expression in villous trophoblasts is negatively influenced by platelet-derived factors, which could contribute to down-regulation of placental S1PR2 over time of gestation as platelet presence and activation in the intervillous space increases from the middle of the first trimester onwards.

Placental Endocrine Activity: Adaptation and Disruption of Maternal Glucose Metabolism in Pregnancy and the Influence of Fetal Sex.

The placenta is an endocrine fetal organ, which secretes a plethora of steroid- and proteo-hormones, metabolic proteins, growth factors, and cytokines in order to adapt maternal physiology to pregnancy. Central to the growth of the fetus is the supply with nutrients, foremost with glucose. Therefore, during pregnancy, maternal insulin resistance arises, which elevates maternal blood glucose levels, and consequently ensures an adequate glucose supply for the developing fetus. At the same time, maternal ß-cell mass and function increase to compensate for the higher insulin demand. These adaptations are also regulated by the endocrine function of the placenta. Excessive insulin resistance or the inability to increase insulin production accordingly disrupts physiological modulation of pregnancy mediated glucose metabolism and may cause maternal gestational diabetes (GDM). A growing body of evidence suggests that this adaptation of maternal glucose metabolism differs between pregnancies carrying a girl vs. pregnancies carrying a boy. Moreover, the risk of developing GDM differs depending on the sex of the fetus. Sex differences in placenta derived hormones and bioactive proteins, which adapt and modulate maternal glucose metabolism, are likely to contribute to this sexual dimorphism. This review provides an overview on the adaptation and maladaptation of maternal glucose metabolism by placenta-derived factors, and highlights sex differences in this regulatory network.

The Fetal Posterior Fossa on Prenatal Ultrasound Imaging: Normal Longitudinal Development and Posterior Fossa Anomalies.

Fetal neurosonography and the assessment of the posterior fossa have gained in importance during the last 2 decades primarily due to the development of high-resolution ultrasound probes and the introduction of 3 D sonography. The anatomical development of the posterior fossa can be visualized well with the newest ultrasound technologies. This allows better knowledge of the anatomical structures and helps with understanding of the development of malformations of the posterior fossa. In this article the longitudinal development of the posterior fossa structures will be reviewed. The embryologic description will be compared with ultrasound descriptions. These embryologic and anatomic illustrations form the basis for the screening and diagnosis of malformations of the posterior fossa. During the first trimester, screening for open spina bifida as well as cystic malformations of the posterior fossa is possible. In the second and third trimester, malformations of the posterior fossa can be subdivided into 3 groups: fluid accumulation in the posterior fossa (Dandy-Walker malformation, Blake's pouch cyst, mega cisterna magna, arachnoid cyst, vermian hypoplasia), decreased cerebellar biometrics (volume) (cerebellar hypoplasia, pontocerebellar hypoplasia) and suspicious cerebellar anatomy (Arnold-Chiari malformation, rhombencephalosynapsis, Joubert syndrome). This algorithm, in combination with knowledge of normal development, facilitates the diagnostic workup of malformations of the posterior fossa.

The impact of severe preeclampsia on maternal quality of life.

PURPOSE: Preeclampsia (PE) is a serious life event that can change women's psychological profile. The aim of this study was to evaluate the physical and mental health-related quality of life (HR-QoL) in women after PE and the impact of contributing factors. METHODS: Ninety-five women who had suffered from PE answered the Short-Form-12 Health Survey on general state of health. Comparison was made with the reference values and among the study cohorts, namely mild (14.7 %), severe (74.7 %) and superimposed PE (10.5 %). Medical parameters were evaluated as additional factors, and age served as covariate. RESULTS: Quality of mental life was significantly worse in all patients (p < 0.01), especially in those after severe PE (p < 0.01) compared to the reference range. These women demonstrated significantly worse results than those affected by the mild form (p = 0.03). Women who had had superimposed PE were neither physically nor mentally impaired compared to the standard population values (p = 0.94 and p = 0.90, respectively). After controlling for medical parameters and age, differences remained statistically significant. Multiparous women scored significantly worse on the mental scale than primiparous (p = 0.02), and pregnant women scored significantly worse than non-pregnant women on the physical level (p = 0.04). CONCLUSIONS: This study shows that women who have suffered from severe PE are substantially reduced in their mental quality of life. An extensive medical care including HR-QoL parameters might improve pregnancy outcome.

Senescent Syncytiotrophoblast Secretion During Early Onset Preeclampsia.

BACKGROUND: Preeclampsia is a severe hypertensive disorder in pregnancy that causes preterm delivery, maternal and fetal morbidity, mortality, and life-long sequelae. Understanding the pathogenesis of preeclampsia is a critical first step toward protecting mother and child from this syndrome and increased risk of cardiovascular disease later in life. However, effective early predictive tests and therapies for preeclampsia are scarce. METHODS: To identify novel markers and signaling pathways for early onset preeclampsia, we profiled human maternal-fetal interface units (fetal villi and maternal decidua) from early onset preeclampsia and healthy controls using single-nucleus RNA sequencing combined with spatial transcriptomics. The placental syncytiotrophoblast is in direct contact with maternal blood and forms the barrier between fetal and maternal circulation. RESULTS: We identified different transcriptomic states of the endocrine syncytiotrophoblast nuclei with patterns of dysregulation associated with a senescence-associated secretory phenotype and a spatial dysregulation of senescence in the placental trophoblast layer. Elevated senescence markers were validated in placental tissues of clinical multicenter cohorts. Importantly, several secreted senescence-associated secretory phenotype factors were elevated in maternal blood already in the first trimester. We verified the secreted senescence markers, PAI-1 (plasminogen activator inhibitor 1) and activin A, as identified in our single-nucleus RNA sequencing model as predictive markers before clinical preeclampsia diagnosis. CONCLUSIONS: This indicates that increased syncytiotrophoblast senescence appears weeks before clinical manifestation of early onset preeclampsia, suggesting that the dysregulated preeclamptic placenta starts with higher cell maturation resulting in premature and increased senescence-associated secretory phenotype release. These senescence-associated secretory phenotype markers may serve as an additional early diagnostic tool for this syndrome.

The impact of resilience on psychological outcomes in women after preeclampsia: an observational cohort study.

BACKGROUND: Preeclampsia is a frequent obstetric complication which affects the mother`s and the fetus's health and can be life threatening. It also has an impact on psychological outcomes. There may be protective variables such as resilience shielding against psychosocial distress in women experiencing these pregnancy complications. The aim of this study was to examine differences in resilience in terms of quality of life, depression and post-traumatic stress symptoms in women after preeclampsia. METHODS: Four international validated questionnaires were used to measure the psychological outcomes (Medical Outcome Study Short-Form SF12, Edinburgh Postnatal Depression Scale EPDS, Resilience Scale RS13, Impact of Event Scale IES-R). Statistical analyses were performed using independent-samples t-test and chi-square test. RESULTS: 67 women with previous preeclampsia returned the questionnaires. Women with high resilience showed significantly less depression (p = 0.001) and better mental quality of life (p = 0.002) compared to women with low resilience. No group differences were found on the medical and socio-demographic characteristics. CONCLUSIONS: Resilience has an important impact on the psychological outcomes in women after preeclampsia. A screening for resilience, depression and quality of life may be appropriate to identify these women.

CD39 abrogates platelet-derived factors induced IL-1ß expression in the human placenta.

Tissue insults in response to inflammation, hypoxia and ischemia are accompanied by the release of ATP into the extracellular space. There, ATP modulates several pathological processes, including chemotaxis, inflammasome induction and platelet activation. ATP hydrolysis is significantly enhanced in human pregnancy, suggesting that increased conversion of extracellular ATP is an important anti-inflammatory process in preventing exaggerated inflammation, platelet activation and hemostasis in gestation. Extracellular ATP is converted into AMP, and subsequently into adenosine by the two major nucleotide-metabolizing enzymes CD39 and CD73. Here, we aimed to elucidate developmental changes of placental CD39 and CD73 over gestation, compared their expression in placental tissue from patients with preeclampsia and healthy controls, and analyzed their regulation in response to platelet-derived factors and different oxygen conditions in placental explants as well as the trophoblast cell line BeWo. Linear regression analysis showed a significant increase in placental CD39 expression, while at the same time CD73 levels declined at term of pregnancy. Neither maternal smoking during first trimester, fetal sex, maternal age, nor maternal BMI revealed any effects on placental CD39 and CD73 expression. Immunohistochemistry detected both, CD39 and CD73, predominantly in the syncytiotrophoblast layer. Placental CD39 and CD73 expression were significantly increased in pregnancies complicated with preeclampsia, when compared to controls. Cultivation of placental explants under different oxygen conditions had no effect on the ectonucleotidases, whereas presence of platelet releasate from pregnant women led to deregulated CD39 expression. Overexpression of recombinant human CD39 in BeWo cells decreased extracellular ATP levels after culture in presence of platelet-derived factors. Moreover, platelet-derived factors-induced upregulation of the pro-inflammatory cytokine, interleukin-1ß, was abolished by CD39 overexpression. Our study shows that placental CD39 is upregulated in preeclampsia, suggesting an increasing demand for extracellular ATP hydrolysis at the utero-placental interface. Increased placental CD39 in response to platelet-derived factors may lead to enhanced conversion of extracellular ATP levels, which in turn could represent an important anti-coagulant defense mechanism of the placenta.

Maternal Resilience and Postpartum Depression at the Neonatal Intensive Care Unit.

Background: The neonatal intensive care unit causes maternal stress and postpartum depressive symptoms in preterm and term mothers. Personal resources like maternal resilience are usually not considered in counselling these women. Objective: This study aims to evaluate the resilience and differences in postpartum depression after admission of newborns at the neonatal intensive care unit. Methods: This prospective pilot study was conducted in a single teaching hospital in Austria from December 2016 until December 2018. Sixty women completed two internationally validated questionnaires, the Edinburgh Postnatal Depression Scale (EPDS) to evaluate depressive symptoms and the Resilience Scale RS-13 to measure maternal resilience during the postpartum period (3 to 10 days postpartum). Additionally, women answered two open questions about burdens and relief. Results: Twenty women (34%) showed lower resilience scores. The 39 high-resilient women (66%) showed significantly less depression (p = 0.005). Women reported social support from their partner (n = 15), health professionals and psychologists (n = 15), family and friends (n = 12), and child-specific relief, e.g., spending time with the newborn and involvement in care (n = 7) as the most helpful variable during the first postpartum period. Conclusion: The experience of having a newborn at the neonatal intensive care unit is a challenging event for women. Women have different resilience parameters. Mothers with lower resilience will benefit from social support and emotional health-promoting activities.

Neonates in the Intensive Care Unit: Maternal Health-Related Quality of Life and Depression After Term and Preterm Births.

Background/Objective: To examine maternal physical and mental health-related quality of life (HRQoL) and depression after early and late preterm and term births in the early postpartum period. Method: In a prospective pilot study, three groups of women whose newborns had to be treated in the neonatal ward during the immediate postpartum period were established and compared with each other: 20 women with extremely to very preterm birth, 20 with moderate to late preterm birth and 20 women with term birth. All participants completed the Short Form-12 Health Survey (SF-12) to measure HRQoL, and the Edinburgh Postnatal Depression Scale (EPDS) to detect depressive symptoms combined with independently developed questions to evaluate anxiety and psychological distress. Results: Maternal psychological HRQoL was significantly worse in the very preterm birth group compared to moderate to late preterm birth (p < 0.001) and full-term birth groups (p = 0.004). There were no differences between the birth groups in depressive symptoms (p = 0.083), anxiety (p = 0.238), perceived stress (p = 0.340) and the general psychological distress values (p = 0.755). In the EPDS, the depression screening instrument 30 to 65% were beyond the cut-off-value to detect major depression. Conclusions: During the early postpartum period, an extensive medical care focussing on acute stress, HRQoL parameters and depression may be a good step to improving maternal well-being.

Comparison of mean platelet volume (MPV) and sFlt-1/PlGF ratio as predictive markers for preeclampsia.

INTRODUCTION: Preeclampsia is characterised by an increased platelet consumption with consecutive reduction of overall platelet count and a consecutive rise in mean platelet volume (MPV). MPV has therefore been suggested as a predictive marker for preeclampsia. We aimed to investigate MPV longitudinally in women with preeclampsia compared to healthy controls during pregnancy for potential early detection of preeclampsia and to compare potential MPV changes against the sFlt-1/PlGF ratio. STUDY DESIGN: This longitudinal study included 38 women with preeclampsia and 84 women with normal pregnancies, where MPV and sFlt-1 and PLGF levels were determined every 4 weeks, starting in early pregnancy. RESULTS: MPV was significantly higher in women who developed preeclampsia compared to women with normal pregnancies at 12, (p = .029), 24 (p = .011), 28 (p = .037), 32 (p = .002), and 36 weeks of gestation, respectively (p = .015). Further analysis revealed a cut-off point of 10.85 fl (sensitivity 65.6%, specificity 26.2%) for the prediction of preeclampsia. The sFlt-1/PlGF ratio was significantly higher in women who developed preeclampsia compared to women with normal pregnancies at the same time points (p = .001). The cut-off point for predicting preeclampsia was 10.3 (sensitivity 87.5%, specificity 11.9%). ROC curve analysis showed that MPV has a high predictive value for early-onset preeclampsia (p < .05) but not for late-onset preeclampsia. CONCLUSION: MPV is significantly elevated even in early pregnancy in women who develop preeclampsia and seems, therefore, a valuable predictor for preeclampsia even at early gestation. However, according to our results, MPV seems reliable in predicting early onset preeclampsia.

Maternal Angiotensin Increases Placental Leptin in Early Gestation via an Alternative Renin-Angiotensin System Pathway: Suggesting a Link to Preeclampsia.

[Figure: see text].

Preeclampsia before fetal viability in women with primary antiphospholipid syndrome- materno-fetal outcomes in a series of 7 cases.

INTRODUCTION: Preeclampsia complicates about 10-17 % of pregnancies with antiphospholipid syndrome (APS). It is often severe and might occur sometimes at early gestation. The development of preeclampsia before fetal viability is a huge challenge for obstetricians and demands an intensive discussion regarding the therapeutical options. PATIENTS AND METHODS: We retrospectively reviewed the data of 7 women with primary APS who developed preeclampsia before 24 weeks of gestation. Plasma exchange had been performed in four of the cases and two women received corticosteroids. One of the women had received 20 mg of pravastatin daily, starting at 18 weeks of gestation. Neonatal outcome was: live birth in four cases and IUFD in three cases. The main pediatric complications were noted in a 28-week-old premature born boy, who developed severe IRDS and thrombocytopenia. At the present time, the boy continues to have a retarded status. DISCUSSION: This retrospective analysis revealed that women with APS can develop severe preeclampsia even before 20 weeks of gestation. Several management options for prolongation of pregnancy such as plasma exchange, pravastatin, LMHW, hydroxychloroquine/HCQ, or TNF-alpha blocker should be discussed with the patients. Optimal management of preeclampsia before 24 weeks of gestation usually depends on weighing the maternal and fetal complications from expectant management with prolongation of pregnancy versus the predominant fetal and neonatal risks of extreme prematurity from "aggressive" management with immediate delivery.

Changes of platelet count throughout pregnancy in women with antiphospholipid syndrome.

OBJECTIVE: Antiphospholipid antibodies (aPL) activate several cell types, such as endothelial cells, monocytes, neutrophils, fibroblasts, trophoblasts and platelets, thus leading to thrombosis and obstetric complications in patients with antiphospholipid syndrome (APS). The aim of the present study was the longitudinal investigation of platelet count in women with APS. Additionally, platelet count in women with APS who developed preeclampsia during pregnancy were compared to women with APS and uncomplicated pregnancy for potential early detection of preeclampsia. MATERIAL AND METHODS: This longitudinal study included 65 women with APS, 38 women with preeclampsia and 84 women with normal pregnancies, where platelet count was determined every four weeks, starting in early pregnancy. RESULTS: Platelet count was significantly lower in women with APS compared to women who developed preeclampsia and normal pregnancies starting at 12 weeks of gestation. The areas under the curve (AUC) for platelet count were 0.765 at 12 weeks of gestation (95% of CI of 0.634-0.896), 0.747 at 20 weeks (95% of CI of 0.600-0.894), 0.719 at 24 weeks (95% of CI of 0.555-0.882), respectively. The cut off points for platelets were 216 at 12-14 weeks of gestation, 226.5 at 20 weeks of gestation, and 163.5 at 24 weeks of gestation, respectively. DISCUSSION: We demonstrated a significant lower platelet count in women with APS throughout gestation. Additionally, platelet count is significantly decreased in women with APS who developed preeclampsia. According to our results, platelet count seems to have a predictive value for the development of preeclampsia in these women.

Effect of Low-Dose Aspirin on Soluble FMS-Like Tyrosine Kinase 1/Placental Growth Factor (sFlt-1/PlGF Ratio) in Pregnancies at High Risk for the Development of Preeclampsia.

BACKGROUND: Soluble FMS-like Tyrosine Kinase 1 (sFlt-1) and placental growth factor (PlGF) have been reported to be highly predictive several weeks before the onset of preeclampsia. OBJECTIVE: To investigate longitudinal changes of serum levels sFlt-1 and PlGF in pregnant women at high risk for the development of preeclampsia and to reveal an impact of aspirin on maternal serum concentrations of sFlt-1 and PlGF. METHODS: This was a prospective longitudinal study in 394 women with various risk factors for the development of preeclampsia (chronic hypertension, antiphospholipid syndrome/APS or systemic lupus erythematosus/SLE, thrombophilia, women with a history of preeclampsia, pathologic first trimester screening for preeclampsia) and 68 healthy women. Serum levels of sFlt-1 and PlGF were measured prospectively at 4-week intervals (from gestational weeks 12 until postpartum). RESULTS: The sFlt-1/PlGF ratio was significantly higher in women with an adverse obstetric outcome compared to women with a normal pregnancy, starting between 20 and 24 weeks of gestation. There was no effect of aspirin on sFlt-1/PlGF ratio in women with chronic hypertension, APS/SLE, thrombophilia and controls. The use of aspirin showed a trend towards an improvement of the sFlt-1/PlGF ratio in women with preeclampsia in a previous pregnancy and a significant effect on the sFlt-1/PlGF ratio in women with a pathologic first trimester screening for preeclampsia. CONCLUSIONS: Our findings reveal an impact of aspirin on sFlt-1/PlGF ratio in women with a pathologic first trimester screening for preeclampsia, strongly supporting its prophylactic use.

Angiogenic factors in pregnancies of women with antiphospholipid syndrome and systemic lupus erythematosus.

OBJECTIVES: An imbalance of angiogenic placental factors such as endoglin, soluble fms-like tyrosine kinase 1(sFlt-1) and placental growth factor (PlGF) has been implicated in the pathophysiology of preeclampsia. This study aimed to evaluate serum levels of sFlt-1, PlGF and endoglin in women with primary and secondary antiphospholipid Syndrome (APS) and systemic lupus erythematosus (SLE) longitudinally through pregnancy. MATERIAL AND METHODS: Serum levels of sFlt-1, PlGF and endoglin were measured prospectively at 4-week intervals (from gestational weeks 12-36) in 17 women with primary APS (PAPS), 18 women with secondary APS (SAPS), and 23 women with SLE. RESULTS: 6/17 (35%) of women with PAPS, 3/18 (17%) of women with SAPS, and 2/23 (9%) of women with SLE developed early-onset preeclampsia. Women who developed preeclampsia had significantly higher mean sFlt-1 and endoglin levels, higher sFlt-1/PlGF ratios, and lower mean PlGF-levels than women who did not. These changes became statistically significant at 12 weeks for sFlt-1, PlGF and endoglin. DISCUSSION: Endoglin, sFlt-1 and PlGF are potential early screening parameters for the development of preeclampsia in pregnant women with autoimmune diseases like APS and SLE.

Risk assessment for preterm preeclampsia in first trimester: Comparison of three calculation algorithms.

OBJECTIVE: To better adjust the risk for preeclampsia, multifactorial models in first trimester of pregnancy have found the way in clinical practice. This study compares the available test algorithms. STUDY DESIGN: In a cross-sectional study between November 2013 and April 2016 we compared the tests results of three first trimester testing algorithms for preeclampsia in 413 women. Risk for preterm preeclampsia was calculated with three different algorithms: Preeclampsia Predictor™ Software by PerkinElmer (PERK), ViewPoint® Software by GE Healthcare (VP) and the online calculator of the Fetal Medicine Foundation (FMF).We analyzed the data descriptively and determined Cohen's Kappa to assess the agreement among the algorithms. RESULTS: VP classified 89(21.5%) women, PERK 43(10.4%) women and FMF 90 (21.8%) women as having high risk for preterm preeclampsia (<34 weeks of gestation for VP and PERK and <37 weeks of gestation for FMF). Agreement between tests ranged from moderate to substantial (PERK/VP: κ = 0.56, PERK/ FMF: κ = 0.50, and VP/ FMF: κ = 0.72). CONCLUSION: The three algorithms are similar but not equal. This may depend on chosen cut off, but also on test properties. This study cannot decide which algorithm is the best, but differences in results and cut offs should be taken into account.

Comparison of two-risk assessment algorithms for preeclampsia in first trimester with consecutive intake of low-dose aspirin in the high-risk group - an observational study.

We analyzed outcome of women screened for preeclampsia with two different multifactorial risk algorithms (Predictor®Software by PerkinElmer, PerkinElmer, Waltham, MA; PERK-group: n = 214 and Viewpoint® by GE Healthcare, Dornstadt, Germany; VIEW-group: n = 209) in first trimester. Women at high risk for developing preeclampsia were advised to take low-dose acetylsalicylic acid (LDA). Screening positive rates for early onset preeclampsia differed significantly between the two groups (7.9% versus 26.3%; p = 0.000). According the clinical use of screening test criteria, LDA was prescribed in 63 (29.4%) women in the PE-group and 55 (26.3%) in the VP-group (p = 0.516). There were no differences in onset of preeclampsia [4 (1.9%) versus 6 (2.9%); p = 0.540]. No early or severe preeclampsia occurred in the whole population.

Gestational diabetes: women's concerns, mood state, quality of life and treatment satisfaction.

OBJECTIVE: The aim of this observational cohort study was to explore concerns, mood state, quality of life (QoL) and treatment satisfaction of women treated for gestational diabetes (GDM). METHODS: Twenty-seven diet-treated and 18 insulin-treated women participated in a semi-structured interview and completed a series of three different questionnaires. RESULTS: Qualitative analysis identified "the baby's health" as dominant concern, but also as main motivational treatment factor. Treatment satisfaction was generally high and further increased, whereas QoL and mood state significantly dropped over time. CONCLUSIONS: Acknowledgment of women's concerns and precise information may improve treatment compliance and outcome.

Up-regulation of the endothelin receptor A in placental tissue from first trimester delayed miscarriages.

OBJECTIVE: This study tested the hypothesis that the endothelin (ET)/ET receptor (ETR) system in biologic fluids and in the human placenta is altered in delayed miscarriages as compared to apparently normal early pregnancies (reference group). METHODS: Immunoreactive ET (irET) concentrations were measured in plasma, urine, and cervical smears from 57 pregnant women in the weeks 6 to 14 of gestation (46 delayed miscarriages, 11 references) with radioimmunoassay (RIA). ET-1, ETR-A, and ETR-B mRNA, and ETR protein expression were measured in placental tissue of 45 early pregnancies (31 delayed miscarriages, 14 references) using semiquantitative reverse-transcription polymerase chain reaction (RT-PCR) and immunoblotting, respectively. RESULTS: irET levels in plasma, urine, and cervical smears did not differ between groups. Two prevailing ETR-A and ETR-B proteins were found at 45 and 55 kd, and were distributed similarly in delayed miscarriages and references. ETR-A protein and mRNA levels were 54% (P = .009) and threefold (P = .021) higher, respectively, in delayed miscarriages versus references. There was no difference in placental ETR-B and ET-1 mRNA levels between groups. CONCLUSION: Neither irET nor ET-1 mRNA levels differ between delayed miscarriages and normal early pregnancies. Pregnancies at risk for miscarriage cannot be identified by measurement of ET in plasma, urine, or cervical smears. Within the ET/ETR system, ETR-A is selectively up-regulated in placental tissue of delayed miscarriages as compared to normal pregnancies. ETR protein processing is similar in both groups.