Histological Features of Shallow Placental Implantation Unify Early-Onset and Late-Onset Preeclampsia

Common pathogenesis of early and late preeclampsia: evidence from recurrences and review of the literature

OBJECTIVE

To investigate whether there is an association between the gestational age at the onset of preeclampsia in recurrent cases and the gestational age at the onset of preeclampsia in previous pregnancies.

METHODS

This retrospective nested case-control study was designed to investigate whether gestational age at diagnosis and at delivery in recurrent cases of preeclampsia correlates with gestational age at diagnosis and delivery in the previous cases of preeclampsia in the same individuals. The database of a Ukrainian research network was used to find patients with the diagnosis of preeclampsia between 2019 and 2021. The database was further queried to identify those with a history of preeclampsia in a previous pregnancy. The comparison was made using the Pearson correlation coefficient.

RESULTS

One hundred and three patients who were diagnosed with preeclampsia were identified. Of those, 15 had recurrent preeclampsia, 2 of whom had preeclampsia in 2 previous pregnancies. There was no statistically significant correlation: based on gestational age at delivery R = - 0.28 (P = 0.30; 95% confidence interval (- 0.69 to 0.28) and based on gestational age at the time of diagnosis R = - 0.14 (P = 0.62; - 0.60 to 0.41).

CONCLUSION

Our data do not find an association between the gestational age of recurrent preeclampsia and preeclampsia diagnosed in a previous pregnancy. This supports the idea that there is single pathogenesis for preeclampsia regardless of the gestational age. It suggests that there are variations in the course of preeclampsia that may be determined by the capacity of the compensatory mechanisms.

Late-onset fetal growth restriction management: a national survey

BACKGROUND

Fetal growth restriction (FGR) is an obstetric condition that increases the risk of adverse neonatal outcomes. FGR antenatal care aims to decrease fetal morbidity and mortality through optimal fetal monitoring. However, no univocal strategies for late-onset FGR outpatient management are available, and this survey investigated gynaecologists' attitudes concerning outpatient frequency tests.

METHODS

We mailed a survey to 429 Italian gynaecologists. The primary purpose was the ambulatory care of late-onset FGR without doppler alterations evaluation. The queries estimated the self-reported medical practice regarding cardiotocography (CTG) and obstetric ultrasound exams before hospitalization. Statistical analysis was performed with Stata 14.1 (Stata corp., College Station, TX, USA) for symmetrically distributed continuous variables, and the mean differences were analyzed using the t-test. Where appropriate, the proportions between the groups were evaluated using Fisher's exact or χ2 test. All P value <0.05 were considered statistically significant.

RESULTS

128 responses (29.8%) from the 429 SCCAL members were available for the survey. 39.9% of respondents had a late FGR standardized protocol. Regarding non-severe FGR with normal fetal doppler, 70.8% suggested a fetal doppler study after one week (92/128), 13.8% (18/128) and 6.9% (9/128) proposed the exam, respectively, two and three times for a week. 0.8% (1/128) of respondents had a daily doppler exam, 7.7% (10/128) did not answer, and 3.1% (4/128) repeated the ultrasound exam to time for a week. The antenatal CTG was offered: 70.8% (92/128) of gynaecologists recommended one weekly CTG, whereas 13.8% (18/128) suggested two. 6.9% (9/128) recommended three weekly tests and 0.8% a daily test. 7.7% (10/128) of gynaecologists did not respond. At least, we investigated the gynaecologist's recommendations for outpatient EFW evaluation: 59.4% (76/128) repeated EFW after two weeks, 31.3% (40/128) after one week. 3.9% (4/128) and 3.1 (4/128) recommended EFW after three weeks and twice a week.

CONCLUSIONS

Gynaecologists recommend unnecessary cardiotocography and ultrasound Doppler exams for non-severe late-onset FGR with normal doppler. However, additional studies and comprehensive surveys are needed to support a standardized protocol and assess the feto-maternal outcomes impact.

Comparison of immune-related gene signatures and immune infiltration features in early- and late-onset preeclampsia

BACKGROUND

Preeclampsia, a severe pregnancy syndrome, is widely accepted divided into early- and late-onset preeclampsia (EOPE and LOPE) based on the onset time of preeclampsia, with distinct pathophysiological origins. However, the molecular mechanism especially immune-related mechanisms for EOPE and LOPE is currently obscure. In the present study, we focused on placental immune alterations between EOPE and LOPE and search for immune-related biomarkers that could potentially serve as potential therapeutic targets through bioinformatic analysis.

METHODS

The gene expression profiling data was obtained from the Gene Expression Omnibus database. ESTIMATE algorithm and Gene Set Enrichment Analysis were employed to evaluate the immune status. The intersection of differentially expressed genes in GSE74341 series and immune-related genes set screened differentially expressed immune-related genes. Protein-protein interaction network and random forest were used to identify hub genes with a validation by a quantitative real-time PCR. Kyoto Encyclopedia of Genes and Genomes pathways, Gene Ontology and gene set variation analysis were utilized to conduct biological function and pathway enrichment analyses. Single-sample gene set enrichment analysis and CIBERSORTx tools were employed to calculate the immune cell infiltration score. Correlation analyses were evaluated by Pearson correlation analysis. Hub genes-miRNA network was performed by the NetworkAnalyst online tool.

RESULTS

Immune score and stromal score were all lower in EOPE samples. The immune system-related gene set was significantly downregulated in EOPE compared to LOPE samples. Four hub differentially expressed immune-related genes (IL15, GZMB, IL1B and CXCL12) were identified based on a protein-protein interaction network and random forest. Quantitative real-time polymerase chain reaction validated the lower expression levels of four hub genes in EOPE compared to LOPE samples. Immune cell infiltration analysis found that innate and adaptive immune cells were apparent lacking in EOPE samples compared to LOPE samples. Cytokine-cytokine receptor, para-inflammation, major histocompatibility complex class I and T cell co-stimulation pathways were significantly deficient and highly correlated with hub genes. We constructed a hub genes-miRNA regulatory network, revealing the correlation between hub genes and hsa-miR-374a-5p, hsa-miR-203a-3p, hsa-miR-128-3p, hsa-miR-155-3p, hsa-miR-129-2-3p and hsa-miR-7-5p.

CONCLUSIONS

The innate and adaptive immune systems were severely impaired in placentas of EOPE. Four immune-related genes (IL15, GZMB, IL1B and CXCL12) were closely correlated with immune-related pathogenesis of EOPE. The result of our study may provide a new basis for discriminating between EOPE and LOPE and acknowledging the role of the immune landscape in the eventual interference and tailored treatment of EOPE.

Outcome-Based Risk Stratification Model for the Diagnosis of Placental Maternal Vascular Malperfusion

The Amsterdam Consensus Statement introduced the term maternal vascular malperfusion (MVM) to group a constellation of findings associated with impaired maternal-placental circulation. In isolation, these findings are relatively common in placentas from normal gestations, and there is uncertainty on how many, and which, are required. We aimed to determine the criteria essential for MVM diagnosis in correlation with obstetrical outcomes. A total of 200 placentas (100 with a reported diagnosis of MVM and 100 controls matched by maternal age and gravida-para-abortus status) were reviewed to document MVM features. Obstetrical outcomes in the current pregnancy were recorded including hypertension, pre-eclampsia with or without severe features, gestational diabetes, prematurity, fetal growth restriction, and intrauterine fetal demise. On univariate logistic regression analysis, adverse outcome was associated with low placental weight (LPW, <10% percentile for gestational age), accelerated villous maturation (AVM), decidual arteriopathy (DA), infarcts (presence and volume), distal villous hypoplasia, and excess multinucleated trophoblast in basal plate ≥2 mm (all P < .01) but not with retroplacental hemorrhage. In a multivariable model DA, infarcts and AVM were significantly associated with adverse outcomes, whereas LPW showed a trend toward significance. A receiver-operating characteristic curve including these 4 parameters showed good predictive ability (area under the curve [AUC], 0.8256). Based on the probability of an adverse outcome, we recommend consistent reporting of DA, AVM, infarcts, and LPW, summarizing them as "diagnostic of MVM" (DA or AVM plus any other feature, yielding a probability of 65%-97% for adverse obstetrical outcomes) or "suggestive of MVM" (if only 1 feature is present, or only 2 features are infarcts plus LPW, yielding a probability of up to 52%). Other features such as distal villous hypoplasia, excess (≥2 mm) multinucleated trophoblast, and retroplacental hemorrhage can also be reported, and their role in MVM diagnosis should be further studied.

Shallow Placentation: A Distinct Category of Placental Lesions

OBJECTIVE

Shallow placental implantation (SPI) features placental maldistribution of extravillous trophoblasts and includes excessive amount of extravillous trophoblasts, chorionic microcysts in the membranes and chorionic disc, and decidual clusters of multinucleate trophoblasts. The histological lesions were previously and individually reported in association with various clinical and placental abnormalities. This retrospective statistical analysis of a large placental database from high-risk pregnancy statistically compares placentas with and without a composite group of features of SPI.

STUDY DESIGN

Twenty-four independent abnormal clinical and 44 other than SPI placental phenotypes were compared between 4,930 placentas without (group 1) and 1,283 placentas with one or more histological features of SPI (composite SPI group; group 2). Placentas were received for pathology examination at a discretion of obstetricians. Placental lesion terminology was consistent with the Amsterdam criteria, with addition of other lesions described more recently.

RESULTS

Cases of group 2 featured statistically and significantly (p < 0.001after Bonferroni's correction) more common than group 1 on the following measures: gestational hypertension, preeclampsia, oligohydramnios, polyhydramnios, abnormal Dopplers, induction of labor, cesarean section, perinatal mortality, fetal growth restriction, stay in neonatal intensive care unit (NICU), congenital malformation, deep meconium penetration, intravillous hemorrhage, villous infarction, membrane laminar necrosis, fetal blood erythroblastosis, decidual arteriopathy (hypertrophic and atherosis), chronic hypoxic injury (uterine and postuterine), intervillous thrombus, segmental and global fetal vascular malperfusion, various umbilical cord abnormalities, and basal plate myometrial fibers.

CONCLUSION

SPI placentas were statistically and significantly associated with 48% abnormal independent clinical and 51% independent abnormal placental phenotypes such as acute and chronic hypoxic lesions, fetal vascular malperfusion, umbilical cord abnormalities, and basal plate myometrial fibers among others. Therefore, SPI should be regarded as a category of placental lesions related to maternal vascular malperfusion and the "Great Obstetrical Syndromes."

KEY POINTS

· SPI reflects abnormal distribution of extravillous trophoblasts.. · SPI features abnormal clinical and placental phenotypes.. · SPI portends increased risk of complicated perinatal outcome..

Patterns of placental pathology associated with preeclampsia

INTRODUCTION

Maternal vascular malperfusion (MVM) is commonly observed in early onset preeclampsia, but less prevalent in late onset preeclampsia. The purpose of our analysis was to investigate patterns of placental pathology in preeclampsia.

METHODS

Electronic health records for all singleton livebirths from 2009 to 2018 at a single institution with a diagnosis of preeclampsia were obtained. Text searching was used to obtain placental data from pathology reports, including lesions of MVM, fetal vascular malperfusion (FVM), chronic inflammation (CI), and acute inflammation (AI). Placental pathology was compared based on timing of delivery and latent class analysis (LCA) was used to investigate subtypes of preeclampsia based on 22 placental variables.

RESULTS

728 patients were included in the analysis. Prevalence of MVM decreased with advancing gestation (95.4% at <34 weeks, 69.8% at 34-36 weeks, and 50%, ≥37 weeks; p < 0.01). LCA identified five classes based on placental pathology: (1) high grade MVM, (2) CI and FVM, (3) low grade MVM, (4) AI, (5) other. Preterm birth varied across the classes (p < 0.01), with the highest prevalence observed among the classes characterized by MVM (high grade: 87.6%; low grade: 63.0%) and the lowest prevalence among the class characterized by AI (23.5%).

DISCUSSION

Placental pathology in preeclampsia differs based on gestational age at delivery with MVM seen in nearly all early onset preeclampsia cases. Latent classes largely grouped by previously defined patterns of placental injury (MVM, CI, FVM, AI), and again revealed the highest likelihood of preterm birth in classes characterized by MVM. Results suggest there may be multiple mechanisms leading to the clinical manifestations of preeclampsia.

Placental lesions attributed to shallow implantation, excess extravillous trophoblast and decidual hypoxia: Correlation with maternal vascular malperfusion and related obstetric conditions

INTRODUCTION

Maternal vascular malperfusion (MVM) is one of four main patterns of placental injury defined by the Amsterdam consensus statement and is associated with adverse fetal and maternal outcomes. Laminar decidual necrosis (DLN), extravillous trophoblast islands (ETIs), placental septa (PS), and basal plate multinucleate implantation-type trophoblasts (MNTs) are lesions attributed to decidual hypoxia, excess trophoblast, and shallow implantation, but are not included in the current MVM diagnostic criteria. We aimed to investigate the relationship between these lesions and MVM.

METHODS

A case-control model was used to evaluate for DLN, ETIs, PS, and MNTs. Placentas with MVM on pathologic examination (defined as ≥2 related lesions) constituted the case group, and maternal age- and GPA-status-matched placentas with less than 2 lesions constituted the control group. MVM-related obstetric morbidities were recorded, including hypertension, preeclampsia, and diabetes. These were correlated with the lesions of interest.

RESULTS

200 placentas were reviewed: 100 MVM cases and 100 controls. MNTs and PS showed significant enrichment in the MVM group (p < .05). Furthermore, larger foci of MNTs (>2 mm linear extent) were significantly associated with chronic or gestational hypertension (OR = 4.10; p < .05) and preeclampsia (OR = 8.14; p < .05). DLN extent correlated with placental infarction, but DLN and ETIs (including size and number) lacked association with MVM-related clinical conditions.

DISCUSSION

As a marker of abnormally shallow placentation and related maternal morbidities, MNT merits inclusion within the MVM pathologic spectrum. Consistent reporting of MNTs >2 mm in size is recommended, as these lesions correlate with other MVM lesions and MVM-predisposing morbidities. Other lesions, particularly DLN and ETI, lacked such association questioning their diagnostic utility.

Cesarean section per se is not a risk factor for non-anatomical placenta creta

OBJECTIVE

To investigate whether mild forms of placenta creta (MPC) are more common in placentas delivered by cesarean section for non-anatomical indications than in placentas from vaginal deliveries.

METHODS

This is a retrospective clinical study in which MPC was diagnosed histologically by the presence of myometrial fibers in the decidua basalis or parietalis or in direct contact with the Rohr fibrinoid or chorionic villi. After excluding 111 cases at high risk for anatomical PC, placentas from 830 consecutive cesarean deliveries (group 1) were retrospectively statistically compared with 907 placentas from vaginal deliveries (group 2).

RESULTS

Statistically significant differences were found in six independent clinical and seven placental phenotypes. More frequently, pre-eclampsia, abnormal fetal heart rate tracing and umbilical artery Dopplers, hypercoiled umbilical cord, diffuse postuterine pattern of chronic hypoxic placental injury, and clusters of avascular or mineralized chorionic villi were found in group 1, while preterm delivery, induction of labor, and histological patterns related to stillbirth were observed in group 2.

CONCLUSION

MPC diagnosed in placentas from cesarean sections performed for non-anatomical indications is not statistically significantly more common than in those after vaginal delivery. Therefore, MPC may feature similar diagnostic correlations and portend a similar prognosis for future pregnancies.

Clinical Utility of the Prenatal Ultrasound Score of the Placenta Combined with Magnetic Resonance Imaging in Diagnosis of Placenta Accreta during the Second and Third Trimester of Pregnancy

Objective. The aim is to explore the clinical utility of the prenatal ultrasound score of the placenta combined with magnetic resonance imaging (MRI) in diagnosis of placenta accreta during the second and third trimester of pregnancy. Materials and Methods. A total of 108 pregnant women with suspected placenta accreta treated in Wuhan Hankou Hospital and Yantaishan Hospital of Yantai from January 2019 to January 2022 were retrospectively analyzed, the enrolled pregnant women received MRI examination because of suspected results of ultrasonic diagnosis, and by taking pathologic findings as the gold standard, the diagnostic efficacy of the ultrasound score, MRI, and their combination to placenta accreta during the second and third trimester of pregnancy was analyzed, and the diagnostic sensitivity, specificity, the positive predictive value, and the negative predictive value of these diagnostic modalities were evaluated. Results. Among 108 patients with suspected placenta accreta, 75 with pathologically confirmed placenta accreta were included in the accreta group, and 33 without placenta accreta were included in the non-accreta group; no statistical between-group differences in the patients’ age, gestational weeks, educational degree, and other general data were observed ( $P>0.05$ ), but the history of cesarean section, history of induced abortion, and incidence rate of placenta praevia were significantly higher in the accreta group than in the non-accreta group ( $P<0.05$ ); the ultrasound score was significantly higher in the accreta group than in the non-accreta group ( $P<0.05$ ); the incidence rates of signs of “placental heterogeneity” and “bulge of lower segment of the uterus and local thickening of the placenta” were obviously higher in the accreta group than in the non-accreta group ( $P<0.05$ ); according to the comparison with pathologic findings, the accuracy rate, sensitivity, specificity, the positive predictive value, and the negative predictive value of combined diagnosis were significantly higher than those of single application of the ultrasound score and MRI diagnosis ( $P<0.05$ ); and ROC analysis found that the area under the curve of combined diagnosis was obviously larger than that of the ultrasound score and MRI diagnosis ( $P<0.05$ ). Conclusion. A combining prenatal ultrasound score of the placenta with MRI plays an important role in the diagnosis of placenta accreta during the second and third trimester of pregnancy, which can further improve the diagnostic accuracy rate of placenta accreta and provide significant guidance in preventing high-risk complications during the perinatal period.

The etiology of preeclampsia

Preeclampsia is one of the "great obstetrical syndromes" in which multiple and sometimes overlapping pathologic processes activate a common pathway consisting of endothelial cell activation, intravascular inflammation, and syncytiotrophoblast stress. This article reviews the potential etiologies of preeclampsia. The role of uteroplacental ischemia is well-established on the basis of a solid body of clinical and experimental evidence. A causal role for microorganisms has gained recognition through the realization that periodontal disease and maternal gut dysbiosis are linked to atherosclerosis, thus possibly to a subset of patients with preeclampsia. The recent reports indicating that SARS-CoV-2 infection might be causally linked to preeclampsia are reviewed along with the potential mechanisms involved. Particular etiologic factors, such as the breakdown of maternal-fetal immune tolerance (thought to account for the excess of preeclampsia in primipaternity and egg donation), may operate, in part, through uteroplacental ischemia, whereas other factors such as placental aging may operate largely through syncytiotrophoblast stress. This article also examines the association between gestational diabetes mellitus and maternal obesity with preeclampsia. The role of autoimmunity, fetal diseases, and endocrine disorders is discussed. A greater understanding of the etiologic factors of preeclampsia is essential to improve treatment and prevention.

Chronic Villitis of unknown etiology (VUE): Obstetrical features, outcome and treatment

Villitis of unknown etiology (VUE) is characterized by lympho-histiocytic infiltrates, which are predominant within the villous stroma. VUE can be of low grade i.e. affecting less than 10 contiguous villi or high grade with either patchy or diffuse subgroups (the later concerning more than 30 % of distal villi). Several other placental lesions could be associated with VUE, in particular in diffuse subgroups, such as diffuse perivillous fibrin deposition and chronic intervillositis. One of the most characteristic features of VUE is the late onset of fetal growth restriction after 32 weeks of gestation, and earlier detection of villitis should first raise an infectious origin. High grade VUE has been associated with fetal growth restriction, prematurity, fetal deaths, recurrent pregnancy loss, central nervous system injury and is characterized by relatively high risk of recurrence (25-50 %). Prospective and well-designed studies are necessary to determine the real prevalence of these adverse pregnancy events associated with VUE. Data about the management of VUE are extremely scarce and thus no recommendation based on the literature review could be actually done.

Screening of differentially expressed proteins in placentas from patients with late-onset preeclampsia

PURPOSE

Preeclampsia (PE) is a severe disease that endangers the safety of mothers and fetuses worldwide. In the absence of specific treatments, more studies on novel predictive and diagnostic biomarkers for PE are required.

EXPERIMENTAL DESIGN

Data-independent acquisition proteomics, with five biological replicates, was used to investigate the protein expression profiles of placental tissues from patients with PE and normal pregnant women.

RESULTS

In total, 52 differentially expressed proteins (DEPs) were identified, 34 of them were upregulated and 18 downregulated. Bioinformatics analyses revealed that PE was associated with multiple GO terms and KEGG pathways. Arginase-1 (ARG1), ferritin light chain (FTL), and RNA cytidine acetyltransferase (NAT10) were identified as hub proteins, which were further validated in placental tissues and maternal plasma by western blot and ELISA.

CONCLUSIONS AND CLINICAL RELEVANCE

FTL expression was significantly lower in the placental tissues and early and late pregnancy plasma of patients with PE compared to that in normal pregnant women. This study is the first to propose that FTL may be a potential predictive and diagnostic biomarker for PE; it provides a proteomics insight for understanding the pathological mechanism of this disease.

Long-Term Cardiovascular Disease Risk in Women After Hypertensive Disorders of Pregnancy: Recent Advances in Hypertension

Patients with a history of hypertensive disorders of pregnancy (HDP) suffer higher rates of long-term cardiovascular events including heart failure, coronary artery disease, and stroke. Cardiovascular changes during pregnancy can act as a natural stress test, subsequently unmasking latent cardiovascular disease in the form of HDP. Because HDP now affect 10% of pregnancies in the United States, the American Heart Association has called for physicians who provide peripartum care to promote early identification and cardiovascular risk reduction. In this review, we discuss the epidemiology, pathophysiology, and outcomes of HDP-associated cardiovascular disease. In addition, we propose a multi-pronged approach to support cardiovascular risk reduction for women with a history of HDP. Additional research is warranted to define appropriate blood pressure targets in the postpartum period, optimize the use of pregnancy history in risk stratification tools, and clarify the effectiveness of preventive interventions. The highest rates of HDP are in populations with poor access to resources and quality health care, making it a major risk for inequity of care. Interventions to decrease long-term cardiovascular disease risk in women following HDP must also target disparity reduction.

Building a stem cell-based primate uterus

The uterus is the organ for embryo implantation and fetal development. Most current models of the uterus are centred around capturing its function during later stages of pregnancy to increase the survival in pre-term births. However, in vitro models focusing on the uterine tissue itself would allow modelling of pathologies including endometriosis and uterine cancers, and open new avenues to investigate embryo implantation and human development. Motivated by these key questions, we discuss how stem cell-based uteri may be engineered from constituent cell parts, either as advanced self-organising cultures, or by controlled assembly through microfluidic and print-based technologies.

Serum survivin is decreased in women with preeclampsia

Objective: To evaluate the serum survivin level in preeclampsia.Methods: Eighty-eight pregnancies complicated with preeclampsia and 88 gestational-age (GA)-matched uncomplicated pregnancies were evaluated.Results: Mean serum survivin was detected to be significantly decreased in the early- (EOPE) and late-onset (LOPE) preeclampsia subgroups than the GA-matched control-groups; and were comparable in EOPE- and LOPE-groups after correction for GA. Serum survivin had weak negative correlations with systolic and diastolic arterial blood pressure.Conclusion: The serum survivin level was decreased in preeclamptic patients than the GA-matched controls. More comprehensive studies are needed to clarify the timing and extent of placental apoptosis in preeclampsia.

The Role of NF-κB in Uterine Spiral Arteries Remodeling, Insight into the Cornerstone of Preeclampsia

Preeclampsia is one of the three leading causes of maternal morbidity and mortality worldwide. It afflicts 2-8% of pregnancies and is the most common cause of gestational hypertension. This article is focused on nuclear factor kappa B (NF-κB), its role in normal and pathological spiral arteries remodelling and development of preeclampsia, with evaluation if it is a promising therapeutic target. NF-κB is a key mediator of placentation. Since insemination, it stimulates production of proinflammatory cytokines by the uterine epithelium, which leads to activation of macrophages, uterine natural killer cells (uNKs), and other leukocytes. The trophoblast/uNK/macrophage crosstalk is crucial for implantation and spiral arteries remodeling, and NF-κB regulates that process through modification of cytokine expression, as well as cell phenotype and function. In the course of preeclampsia, the remodeling processes is disturbed by excessive inflammation and increased NF-κB activation. The pathological remodeling leads to uteroplacental dysfunction, release of proinflammatory cytokines into the maternal circulation, endothelial stress, and development of preeclampsia. The analysis of genetic and environmental inductors of NF-κB helps to distinguish preeclampsia risk groups. Furthermore, a selective inhibition of NF-κB or NF-κB activating pathways alleviates symptoms of preeclampsia in rat models; therefore, this could be an efficient therapeutic option.

Pathological investigation of placentas in preeclampsia (the PEARL study)

INTRODUCTION: Preeclampsia (PE), but mainly preterm PE, is associated with deep placentation disorders. We aimed to compare placental pathologies in pregnancies affected by term and preterm PE compared to normal pregnancies. METHODS: We performed a prospective case-cohort study. Low-risk nulliparous women were recruited in the first trimester and women who developed PE were recruited at diagnosis. Placental pathologies were reported according to the Amsterdam Placental Workshop Group Consensus Statement and were compared between cases and controls. PE cases stratified as term (≥37 weeks) and preterm PE (<37 weeks). Our primary outcome was maternal vascular malperfusion (MVM). RESULTS: Twenty-four women who developed preterm PE were compared to 10 women who developed term PE and 41 women without PE. Preterm PE (92%) was associated with more MVM than term PE (10%, p < 0.01) and controls (4%, p < 0.01), but the rate of MVM was similar between term PE and controls (p = 0.56). Preterm PE was also associated with more placental infarcts (65% vs. 20% vs. 15%); advanced villous maturation (91% vs. 30% vs. 1%); and hypoplastic villous maturation (70% vs. 10% vs. 3%); and moderate to severe decidual vasculopathy (56% vs. 10% vs. 3%) than term PE and controls (all p < 0.05). CONCLUSION: Most cases of preterm PE are associated with MVM, placental infarcts, advanced and/or hypoplastic villous maturation, and moderate to severe decidual vasculopathy, while it is infrequent in term PE and pregnancies without PE. Preterm and term preeclampsia have a different pathologic process that should be considered for their prevention and clinical management.

Maternal serum endothelial cell-specific molecule-1 level and its correlation with severity of early-onset preeclampsia

Preeclampsia (PE), the primary pathology of which is endothelial cell (EC) dysfunction, has long-lasting effects such as cardiovascular disease. Therefore, it was decided to investigate the maternal serum concentrations of EC-specific molecule-1 in patients with early-onset preeclampsia (E-PE). This study was conducted on 33 pregnant women with E-PE and 35 healthy pregnant women matched for gestational age. EC-specific molecule-1 level was measured using a commercially available enzyme-linked immunosorbent assay kit. The mean EC-specific molecule-1 concentrations were not significantly different between the groups (651.7 ± 632.2 pg/mL vs. 425.9 ± 263.0 pg/mL, p=.056). Among women with E-PE, the median EC-specific molecule-1 concentration did not differ significantly by disease severity (p=.115). EC-specific molecule-1 is not involved in the pathogenesis of E-PE. However, some studies in the literature report that EC-specific molecule-1 concentrations increased during the diagnosis of PE. Therefore, well-designed studies with a large sample are needed in cases of E-PE.Impact StatementWhat is already known on this subject? There is an increased risk of cardiovascular disease (CVD) in early-onset preeclampsia (E-PE) which is linked with endothelial dysfunction. Endothelial cell (EC)-specific molecule-1 stands out as an important marker in EC dysfunction related conditions such as preeclampsia.What the results of this study add? This study showed that EC-specific molecule-1 is not associated with the CVDs risk linked with endothelial dysfunction in E-PE. Additionally, there was also no significant relationship was detected between the severity of E-PE and EC-specific molecule-1 concentrations.What the implications are of these findings for clinical practice and/or further research? Endothelial cell-specific molecule-1 is not involved in the pathogenesis of E-PE. Moreover, advantageous and easy-to-measure markers are needed in larger sample studies to better understand the aetiology of E-PE.

Placenta Creta: A Spectrum of Lesions Associated with Shallow Placental Implantation

Background

On placental histology, placenta creta (PC) ranges from clinical placenta percreta through placenta increta and accreta (clinical and occult) to myometrial fibers with intervening decidua. This retrospective study aimed to investigate the clinicopathologic correlations of these lesions.

Methods

A total of 169 recent consecutive cases with PC (group 1) were compared with 1661 cases without PC examined during the same period (group 2). The frequencies of 25 independent clinical and 40 placental phenotypes were statistically compared between the groups using chi-square test or analysis of variance where appropriate.

Results

Group 1 placentas, as compared with group 2 placentas, were statistically significantly (p < 0.05) associated with caesarean sections (11.2% vs. 7.5%), antepartum hemorrhage (17.7% vs 11.6.%), gestational hypertension (11.2% vs 4.3%), preeclampsia (11.8% vs 2.6%), complicated third stage of labor (18.9% vs 6.4%), villous infarction (14.2% vs 8.9%), chronic hypoxic patterns of placental injury, particularly the uterine pattern (14.8%, vs 9.6%), massive perivillous fibrin deposition (9.5% vs 5.3%), chorionic disc chorionic microcysts (21.9% vs 15.9%), clusters of maternal floor multinucleate trophoblasts (27.8% vs 21.2%), excessive trophoblasts of chorionic disc (24.3% vs 17.3%), segmental fetal vascular malperfusion (27.8% vs 19.9%), and fetal vascular ectasia (26.2% vs 15.2%).

Conclusion

Because of the association of PC with gestational hypertensive diseases, acute and chronic placental hypoxic lesions, increased extravillous trophoblasts in the chorionic disc, chorionic microcysts, and maternal floor trophoblastic giant cells, PC should be regarded as a lesion of abnormal placental implantation and abnormal trophoblast invasion rather than decidual deficiency only.

CXCR4 signaling at the fetal-maternal interface may drive inflammation and syncytia formation during ovine pregnancy†

Early pregnancy features complex signaling between fetal trophoblast cells and maternal endometrium directing major peri-implantation events including localized inflammation and remodeling to establish proper placental development. Proinflammatory mediators are important for conceptus attachment, but a more precise understanding of molecular pathways regulating this process is needed to understand how the endometrium becomes receptive to implantation. Both chemokine ligand 12 (CXCL12) and its receptor CXCR4 are expressed by fetal and maternal tissues. We identified this pair as a critical driver of placental angiogenesis, but their additional importance to inflammation and trophoblast cell survival, proliferation, and invasion imply a role in syncytia formation at the fetal-maternal microenvironment. We hypothesized that CXCL12 encourages both endometrial inflammation and conceptus attachment during implantation. We employed separate ovine studies to (1) characterize endometrial inflammation during early gestation in the ewe, and (2) establish functional implications of CXCL12 at the fetal-maternal interface through targeted intrauterine infusion of the CXCR4 inhibitor AMD3100. Endometrial tissues were evaluated for inflammatory mediators, intracellular signaling events, endometrial modifications, and trophoblast syncytialization using western blotting and immunohistochemistry. Endometrial tissue from ewes receiving CXCR4 inhibitor demonstrated dysregulated inflammation and reduced AKT and NFKB, paired with elevated autophagic activity compared to control. Immunohistochemical observation revealed an impairment in endometrial surface remodeling and diminished trophoblast syncytialization following localized CXCR4 inhibition. These data suggest CXCL12-CXCR4 regulates endometrial inflammation and remodeling for embryonic implantation, and provide insight regarding mechanisms that, when dysregulated, lead to pregnancy pathologies such as intrauterine growth restriction and preeclampsia.

Placental Findings in Postpartum Preeclampsia: A Comparative Retrospective Study

OBJECTIVE

Preeclampsia is a multifactorial placental disease that can occur after delivery. The pathophysiology of postpartum preeclampsia remains unknown. The objective was to describe placental findings in postpartum preeclampsia.

STUDY DESIGN

This is a case-control study, comparing the placental histologic findings in four groups of 30 patients with postpartum preeclampsia, early-onset preeclampsia, late-onset preeclampsia, and normotensive controls.

RESULTS

Placentas of postpartum preeclampsia had a mean placental weight not different from that of late-onset preeclampsia at a similar gestational age (479.0 ± 152.7 vs. 521.3 ± 144.1 g, p = 0.07); they showed a higher rate of acute deciduitis of 42.4% than early preeclampsia (5.7%, p < 0.01) or in controls (3.2%, p < 0.01); 18.2% had decidual arteriolopathy, with no significant difference with other groups. These placentas had fewer villous infarcts as compared with early preeclampsia (9.1 vs. 62.9%, p < 0.01) and less accelerated maturation of villi (24.2 vs. 74.3%, p < 0.01).

CONCLUSION

There were no significant differences for decidual arteriolopathy and villous infarcts among postpartum preeclampsia, late-onset preeclampsia, and the controls. This suggests that postpartum preeclampsia is more of a maternal disease in which the placenta may act as a priming effect in predisposed mothers and becomes clinically apparent after delivery.

Temporal heterogeneity of placental segmental fetal vascular malperfusion: timing but not etiopathogenesis

Clinicopathologic correlations of segmental villous avascularity and other histological lesions of segmental fetal vascular malperfusion (SFVM) were analyzed retrospectively to determine whether lesions of various durations reflect different etiopathogeneses. The frequencies of 25 independent clinical and 43 placental phenotypes were statistically compared by ANOVA or Chi-square among 3 groups containing a total of 378 placentas with SFVM: group 1 contained 44 cases of recent SFVM (endothelial fragmentation, villous hypovascularity by CD34 immunostain, and/or stromal vascular karyorrhexis); group 2 contained 264 cases of established SFVM (clusters of avascular villi); and group 3 contained 70 cases of remote SFVM (villous mineralization). Statistically significant differences among the three study groups (p Bonferroni < 0.002) were found in four clinical variables (gestational age, frequencies of macerated stillbirth, induction of labor, and cesarean section) and in five placental variables (frequencies of fetal vascular ectasia, stem vessel luminal vascular abnormalities, diffusely increased extracellular matrix in chorionic villi, chorionic disk extravillous trophoblast microcysts, and excessive extravillous trophoblasts in the chorionic disc). In summary, the absence of statistically significant differences between the study groups regarding the most common causes of SFVM (hypertensive conditions of pregnancy, diabetes mellitus, fetal anomalies, and clinical and pathological features of umbilical cord compromise) is evidence that the three types of SFVM reflect temporal heterogeneity rather than etiopathogenesis. This evidence can be used to date the onset of fetal vascular malperfusion before delivery or stillbirth. The coexistence of different SVFM lesions of various durations indicates ongoing or repeat occurrences of FVM rather than single episodes.

The relationship among vitamin D, TLR4 pathway and preeclampsia

Preeclampsia is a pregnancy-specific syndrome that has been the greatest cause of maternal and fetal morbidity and mortality. The impaired outcomes are related to maternal and the offspring healthy in the short and long-term. Although preeclampsia origins remain unclear, it is well known that there is impaired trophoblast invasion with culminant abnormal immune response. The early and late-onset preeclampsia have been studied, the subtypes have the same difference in the placentation and inflammatory features. Dietary compounds can stimulate or inhibit the activation of immune cells. Low vitamin D intake has been linked to impaired fetal development, intrauterine growth restriction, and preeclampsia. Vitamin D has been described as an anti-inflammatory effect. It can downregulate pro-inflammatory cytokines expression by the inhibition of the Nuclear Factor-ĸB pathway signaling cascade. High vitamin D levels could attenuate the immune response. On the other hand, vitamin D deficiency may contribute to increasing pro-inflammatory state. In preeclampsia, there is a reduced expression of vitamin D receptor and its metabolism is disrupted. In this review, we aimed to discuss the role of vitamin D as an anti-inflammatory agent in relation to the pro-inflammatory process of preeclampsia through the activation of the TLR4 pathway. Although there are limited studies showing the relation between vitamin D and lower risk of preeclampsia, the maternal status of vitamin D seems to influence the risk of PE development. Therefore, vitamin D supplementation in women may be a strategy to improve pregnancy outcomes.

Placental histopathology in IVF pregnancies resulting from the transfer of frozen-thawed embryos compared with fresh embryos

PURPOSE

To study whether placentas of singleton pregnancies conceived after fresh embryo transfer (ET) contain more histopathological lesions compared with placentas of singleton pregnancies conceived after frozen-thawed embryo transfer (FET).

METHODS

A prospective cohort study of placental histopathology in 131 women with singleton IVF pregnancies who delivered at a single medical center, between December 2017 and May 2019. The prevalence of different placental histopathology lesions was compared between women who conceived after fresh ET and FET.

RESULTS

Women who conceived after fresh ET (n = 74) did not differ from women who conceived after FET (n = 57) with regard to maternal age, BMI, nulliparity, or infertility diagnosis. Gestational week at delivery was lower in pregnancies conceived after fresh ET (38.5 vs. 39.2 weeks, respectively, p = 0.04), and a trend for a lower birthweight following fresh ET was noted (3040 vs. 3216 g, respectively, p = 0.053). However, placental histopathology analysis from pregnancies conceived after fresh ET was comparable to pregnancies conceived after FET, with regard to the prevalence of maternal vascular malperfusion lesions (45.9% vs. 50.9%, respectively, p = 0.57), fetal vascular malperfusion lesions (17.6% vs. 21.1, p = 0.61), acute inflammatory response lesions (28.4% vs. 28.1%, respectively, p = 0.96), and chronic inflammatory response lesions (13.5% vs. 8.8%, respectively, p = 0.48).

CONCLUSION

Placental histopathology did not differ between IVF pregnancies conceived after fresh and frozen ET. These results are reassuring for clinicians and patients who wish to pursue with transferring fresh embryos.

Expression of ACKR2 in placentas from different types of preeclampsia

OBJECTIVE

The purpose of this study was to investigate the expression of atypical chemokine receptor 2 (ACKR2, D6) in different types of preeclampsia (PE) and its effects on trophoblast proliferation and apoptosis.

METHODS

The subjects were divided into four groups: early-onset PE group (EOPE, n = 30), late-onset PE group (LOPE, n = 30), preterm birth group (PB, n = 30), and normal group (N, n = 30). The expression of ACKR2 in placentas was evaluated using immunohistochemistry, qRT-PCR, and Western blot. The trophoblast cell line JAR was cultured to detect the expression of ACKR2 after simulating hypoxic conditions with cobalt chloride (CoCl₂). The effects on cell proliferation, apoptosis, and expression of the chemokine CCL2 were analyzed after silencing ACKR2 with siRNA.

RESULTS

ACKR2 was decreased in placentas of EOPE and PB groups at the protein and mRNA level，compared to the normal group. No statistical differences were found between EOPE and PB groups, or between LOPE and normal groups. In our in vitro work, we found that the expression of ACKR2 decreased after treatment with 150 μmol/L, 200 μmol/L, and 250 μmol/L of CoCl₂. After ACKR2 was silenced, the degree of cellular proliferation decreased, while apoptosis and CCL2 expression increased.

CONCLUSION

The changes of ACKR2 expression in placentas of PE may be related to gestational weeks. Hypoxia inhibits the expression of ACKR2 in placentas. Abnormal expression of ACKR2 in PE may lead to dysfunction of trophoblast, and ACKR2 is an essential player in the immunoregulation of the placental chemokine CCL2.

Patterns of Placental Injury in Congenital Anomalies in Second Half of Pregnancy

BACKGROUND

Placental pathology in fetal congenital anomalies in second half of pregnancy is largely unknown.

METHODS

Twenty-six clinical and 45 independent placental phenotypes from pregnancies ≥20 weeks of gestation with congenital anomalies divided into 4 groups were retrospectively compared with analysis of variance or χ ² with 3 degrees of freedom and with Bonferroni correction for multiple comparisons: group 1 : 112 cases with heart malformations (with or without chromosomal anomalies), group 2 : 41 cases with abnormal karyotypes and anomalies other than heart malformations, group 3 : 87 cases with intrathoracic or intraabdominal mass-forming anomalies (mostly congenital diaphragmatic hernias and adenomatoid airway malformation), and group 4 : 291 miscellaneous cases with mostly skeletal, renal, and central nervous system anomalies not fulfilling the criteria of inclusion into groups 1 to 3.

RESULTS

Eight of 26 clinical (30.8%) and 16 of 45 (35.5%) placental phenotypes varied statistically significantly among the 4 groups (P <  .05), of those, 7 (26.9%) and 4 (8.9%), respectively, remained statistically significant after Bonferroni correction (P Bonferroni ≤  .002). Those placental phenotypes were placental weight, chorionic disc chorionic microcysts, fetal vascular ectasia, and luminal vascular abnormalities of chorionic villi.

CONCLUSIONS

Fetal anomalies in second half of pregnancy feature abnormal clinical phenotypes much more frequently than abnormal placental phenotypes. Chromosomal abnormalities with or without heart malformations tend to feature villous edema, and erythroblastosis of fetal blood, likely due to fetal heart failure. Mass-forming fetal anomalies feature placental histological lesions of shallow placental implantation, diffuse chronic hypoxic patterns of placental injury, and lesions of fetal vascular malperfusion, likely stasis-induced.

Increased levels of serum serglycin and agrin is associated with adverse perinatal outcome in early onset preeclampsia

Goal: Our aim was to determine whether alterations in serum serglycin and agrin levels in early-onset preeclampsia (EOPE) are useful in predicting adverse perinatal outcomes such as fetal growth restriction (FGR), intrauterine fetal demise (IUFD), preterm delivery and/or neonatal unit admission. Materials and Methods: A prospective case-controlled study enrolled 88 pregnant patients (44 EOPE and 44 controls). Maternal serum serglycin and agrin levels were determined before the 34th gestational week by enzyme-linked immunosorbent assay. Results: Compared with controls, women with EOPE had significantly higher serglycin and agrin levels (p = .018; p = .048). Multivariable logistic regression analysis revealed serglycin was independently associated with FGR in EOPE (OR 0.866; 95% CI 0.779-0.953). Agrin was independently associated with IUFD in EOPE (OR 0.757, 95% CI 0.636-0.879). Conclusions: The current study suggests that increased maternal serum serglycin is associated with FGR, and increased maternal serum agrin is associated with IUFD in EOPE.

Segmental villous mineralization: A placental feature of fetal vascular malperfusion

INTRODUCTION

This retrospective analysis was performed to find out if clusters of mineralized chorionic villi can be regarded as an independent feature of fetal vascular malperfusion (FVM).

METHODS

Of all 1698 placentas reviewed by the author during the last 10 years, 39 (2.3%) showed clusters of mineralized chorionic villi (Group 1), 100 cases (5.9%) showed randomly scattered mineralized chorionic villi with without clustering (Group 2), and the remaining 1559 placentas showed no villous mineralization (comparative Group 3). In doubtful cases, histochemistry stains were performed to determine the pattern of villous mineralization. Twenty three independent clinical and 43 placental variables were statistically compared among the groups: descriptive statistics (Chi-square, Fisher test or signed rank test), and logistics regression model.

RESULTS

Clinically, Group 1 featured shorter gestational age than Group 2, and in addition to shorter gestational age, more common oligohydramnios, polyhydramnios, induction of labor, macerated stillbirth and fetal growth restriction than Group 3. Of placental variables, fetal vascular ectasia, and clusters of avascular chorionic villi were more common in Group 1 than in Group 2, and in addition, segmental villous stromal vascular karyorrhexis was more common than in Group 3. By the logistics regression mode, segmental villous mineralization was independently associated with other histological features of FVM as a group and particularly with clusters of sclerotic chorionic villi.

DISCUSSION

FVM is characterized by temporal heterogeneity, i.e. coexistence of lesions of various duration, and strongly and independently correlates with clusters of mineralized chorionic villi. Therefore, segmental villous mineralization should be included into the category of segmental FVM. It can be seen even in totally fibrotic placentas of prolonged stillbirth when other histological features of segmental vascular malperfusion can be obscured by global villous sclerosis.

Interactions between the complement and endothelin systems in normal pregnancy and following placental ischemia

Preeclampsia is characterized by new onset hypertension and fetal growth restriction and is associated with aberrant activation of the innate immune complement system and stressed or ischemic placenta. Previous studies have suggested a role for both endothelin and complement system activation products in new onset hypertension in pregnancy, but inter-relationships of the pathways are unclear. We hypothesized that complement activation following placental ischemia stimulates the endothelin pathway to cause hypertension and impair fetal growth. The Reduced Uterine Perfusion Pressure (RUPP) model results in hypertension and fetal growth restriction in a pregnant rat due to placental ischemia caused by mechanical obstruction of blood flow to uterus and placenta. The effect of inhibitor of complement activation soluble Complement Receptor 1 (sCR1) and endothelin A receptor (ET_A) antagonist atrasentan on hypertension, fetal weight, complement activation (systemic circulating C3a and local C3 placental deposition) and endothelin [circulating endothelin and message for preproendothelin (PPE), ET_A and endothelin B receptor (ET_B) in placenta] in the RUPP rat model were determined. Following placental ischemia, sCR1 attenuated hypertension but increased message for PPE and ET_A in placenta, suggesting complement activation causes hypertension via an endothelin independent pathway. With ET_A antagonism the placental ischemia-induced increase in circulating C3a was unaffected despite inhibition of hypertension, indicating systemic C3a alone is not sufficient. In normal pregnancy, inhibiting complement activation increased plasma endothelin but not placental PPE message. Atrasentan treatment increased fetal weight, circulating endothelin and placental ET_A message, and unexpectedly increased local complement activation in placenta (C3 deposition) but not C3a in circulation, suggesting endothelin controls local placental complement activation in normal pregnancy. Atrasentan also significantly decreased message for endogenous complement regulators Crry and CD55 in placenta and kidney in normal pregnancy. Results of our study indicate that complement/endothelin interactions differ in pregnancies complicated with placental ischemia vs normal pregnancy, as well as locally vs systemically. These data clearly illustrate the complex interplay between complement and endothelin indicating that perturbations of either pathway may affect pregnancy outcomes.

Neurological manifestations and neuroimaging presentations in patients with severe preeclampsia: predisposing factors and clinical implications

BACKGROUND AND PURPOSE

Neurological manifestations and neuroimaging abnormalities are common in patients with severe preeclampsia; however, the differences between these abnormal features occurring during early- and late-onset severe preeclampsia are unclear, and the factors associated with abnormal imaging changes in patients with neurological manifestations have not yet been fully elucidated.

MATERIALS AND METHODS

A retrospective study was conducted on 172 patients with severe preeclampsia from January 2017 to June 2018 in the Department of Neurology and Obstetrics, Shengjing Hospital of China Medical University. The neurological manifestations, clinical parameters, laboratory, and neuroimaging findings were analyzed.

RESULTS

Early- and late-onset preeclampsia were diagnosed in 83 and 89 patients, respectively. Headache and dizziness were more common in patients with early-onset preeclampsia than in patients with late-onset preeclampsia (p = 0.013, p = 0.004, respectively). Serum uric acid, creatinine, and urea nitrogen were significantly elevated in the patients with early-onset preeclampsia (p < 0.001, p = 0.004, and p = 0.005, respectively). Neuroimaging was performed in 81 patients, of which 57 were positive. Findings indicating cerebral edema were the most common neuroimaging abnormality. Gestational weeks (p = 0.014), headache (p < 0.001), and blood urea nitrogen level (p = 0.027) may be associated with positive imaging findings. By multiple logistic regression, headache (OR = 10.2, 95% CI, 2.4-42.7; p = 0.002) proved to be an independent factor associated with neuroimaging abnormality.

CONCLUSIONS

Neurological symptoms such as headache and dizziness were more common in patients with early-onset preeclampsia. Renal dysfunction may also associate with early-onset severe preeclampsia. Cerebral edema was the most common neuroimaging abnormality, and headache might be independently associated with abnormal imagine changes.