The "Great Obstetrical Syndromes" are associated with disorders of deep placentation

The revolutionary role of placental derivatives in biomedical research

The human placenta is a transient yet crucial organ that plays a key role in sustaining the relationship between the maternal and fetal organisms. Despite its historical classification as "biowaste," placental tissues have garnered increasing attention since the early 1900s for their significant medical potential, particularly in wound repair and surgical application. As ethical considerations regarding human placental derivatives have largely been assuaged in many countries, they have gained significant attention due to their versatile applications in various biomedical fields, such as biomedical engineering, regenerative medicine, and pharmacology. Moreover, there is a substantial trend toward various animal product substitutions in laboratory research with human placental derivatives, reflecting a broader commitment to advancing ethical and sustainable research methodologies. This review provides a comprehensive examination of the current applications of human placental derivatives, explores the mechanisms behind their therapeutic effects, and outlines the future potential and directions of this rapidly advancing field.

Impact of Aspirin on Timing of Birth in Pregnancies With Clinical Manifestations of Placental Dysfunction: Evidence From a Multicentre Randomised Clinical Trial

OBJECTIVE

To examine whether aspirin delays gestational age at delivery (GAD) in pregnancies with placental dysfunction (PD) phenotypes (preeclampsia [PE], small-for-gestational-age [SGA], placental abruption and/or stillbirth).

DESIGN

A secondary analysis of a multicentre stepped-wedge cluster randomised trial.

SETTING

18 maternity/diagnostic units in Asia.

POPULATION

Singleton pregnancies examined at 11-13+6 weeks.

METHODS

A model in which the effect of aspirin is to delay the GAD in pregnancies with PD was developed.

MAIN OUTCOME MEASURES

GAD in pregnancies with PD.

RESULTS

Aspirin administration was associated with a significant reduction in PD < 32 weeks (adjusted relative risk 0.543, 95% CI: 0.330-0.864), with a trend for an increase of PD ≥ 32 weeks (test for trend, p-value = 0.0018). Similar findings were observed individually for PE, SGA and/or placental abruption. At 24 weeks, the aspirin-induced prolongation of pregnancies with PD was 2.85 weeks (95% CI: 0.44-5.40), and this effect was decreased by -0.19 weeks (95% CI: -0.33 to -0.05) for each week of gestation; therefore, at 28 and 32 weeks' gestation, the aspirin-induced prolongation was 2.09 and 1.33 weeks, respectively.

CONCLUSIONS

In this secondary analysis of a cluster randomised trial, women at high risk of PE who are destined to develop a clinical spectrum of PD may benefit from longer pregnancy duration through aspirin administration in early pregnancy. Aspirin may delay the GAD due to PD, particularly benefiting those deliveries that would occur at earlier gestations without aspirin administration.

Mechanism of microRNA-152 Regulating Decidual Natural Killer Cell Viability and Affecting Trophoblast Cell Invasiveness via the HLA-G/KIR2DL4 Axis

Trophoblast cells are specialized placental epithelial cells essential for pregnancy maintenance. miR-152 is implicated in trophoblast cell regulation and pregnancy failure. This study explores the role of miR-152 in decidual natural killer (dNK) cell viability and trophoblast cell invasion. HTR-8/SVneo cells were transfected with miR-152-mimics/inhibitor or their respective controls, followed by co-culture with dNK cells. RT-qPCR assessed transfection efficiency, while cytokine secretion (IL-8, IP-10, VEGF), cell viability, apoptosis, and invasion were evaluated via ELISA, CCK-8, flow cytometry, Western blot, and Transwell assays. The interaction between miR-152 and HLA-G was examined via dual-luciferase reporter assay, and HLA-G/sHLA-G levels were measured. Co-cultures of dNK cells and miR-152/HLA-G-overexpressing HTR-8/SVneo cells were established, and anti-KIR2DL4/IgG1 was used to block HLA-G/KIR2DL4 binding. Co-immunoprecipitation confirmed protein interactions. miR-152 overexpression suppressed dNK cell cytokine secretion, reduced HTR-8/SVneo cell viability and invasion, and promoted apoptosis. miR-152 inhibition had the opposite effect. miR-152 directly targeted HLA-G, and HLA-G overexpression rescued dNK function and trophoblast invasion. Blocking the HLA-G/KIR2DL4 binding counteracted the effects of miR-152. miR-152 inhibits dNK cell function and trophoblast invasion by targeting HLA-G, reducing HLA-G/KIR2DL4 interaction. These findings highlight a potential regulatory mechanism in pregnancy maintenance.

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.

Profiling neuroactive steroids in pregnancy. A non-derivatised liquid chromatography tandem mass spectrometry method for the quantitation of allopregnanolone and four related isomers in maternal serum

Neuroactive steroids are metabolites of progesterone, synthesised during pregnancy by the placenta. Here, we describe development of a novel liquid chromatography tandem mass spectrometry (LC-MS/MS) assay for quantitation of allopregnanolone, pregnanolone, isopregnanolone, epipregnanolone and allopregnan-20α-ol-3-one in maternal serum. Following addition of deuterated internal standards, 200 μL of serum was subjected to solid phase extraction. Chromatography was performed using a pentafluorophenyl column, and LC-MS/MS on a Sciex 6500+. Sample injection volume was 20 μL, and injection-to-injection time 10.0 min. The assay was validated according to published guidelines; assay linearity and lower limit of quantification were suitable for analysis of each steroid in maternal serum, for all analytes mean recoveries were 100 % ± 15 %, intra- and inter-assay imprecision <15 %, and matrix effects negligible, and specificity experiments confirmed nil interference from a wide range of endogenous metabolites of progesterone. The method was applied to human serum samples obtained from a large cohort of third trimester pregnancies which were subsequently characterised by normal fetal and maternal outcomes, and relationships between maternal neuroactive steroid concentrations and fetal gestational age assessed. Positive correlations between maternal serum concentration and fetal gestational age were observed for isopregnanolone, allopregnanolone and allopregnan-20α-ol-3-one. The LC-MS/MS method offers significant advantages over previously published approaches for quantitation of neuroactive steroids in human maternal serum, notably obviating the need for derivatisation, whilst achieving exceptional specificity. Characterisation of normal maternal neuroactive steroid concentrations will aid future research as dysregulated placental progesterone metabolism is observed in pregnancies with poor outcomes.

Pregnancy Complications and Risk of Autoimmune Disease in Women: A Systematic Review and Meta-Analysis

Background: Autoimmune diseases disproportionately impact women, and pregnancy-related events could play an underlying role. We summarized literature on the association between pregnancy complications and future risk of autoimmune disease. Materials and Methods: We systematically searched Medline, EMBASE, CINAHL Plus, and Web of Science from database inception to January 2024 for observational studies that reported on history of pregnancy complications (exposure), risk of newly diagnosed autoimmune disease (outcome), and included a comparison group of unaffected women. Two reviewers independently assessed study eligibility, extracted data, and rated risk of bias. We estimated pooled risk ratios (RRs) or odds ratios (ORs) and 95% confidence intervals (CIs) for pregnancy complications with ≥3 identified studies using DerSimonian and Laird random effects models and otherwise summarized findings following synthesis without meta-analysis (SWiM). Results: We screened 7,763 citations and included 25 studies (12 cohort, 13 case-control). Most studies were from Denmark (n = 10) or the United Kingdom (n = 5), with sample sizes ranging from 138 to >1.5 million women (median = 1,304 women). Risk of bias was moderate, serious, and critical in 10, 13, and 2 studies, respectively, with quality adversely impacted by potential unmeasured confounding. Meta-analyses indicated an elevated risk of autoimmune disease following preeclampsia (adjusted RR: 1.61, 95% CI: 0.98-2.65, I2 = 90.0%) and small fetal/infant size (adjusted OR: 2.02, 95% CI: 1.16-3.52, I2 = 28.4%), and possibly spontaneous pregnancy loss (adjusted RR: 1.58, 95% CI: 0.66-3.79, I2 = 99.4%) and stillbirth (adjusted RR: 2.18, 95% CI: 0.65-7.34, I2 = 99.2%), although estimates were often imprecise. SWiM findings generally supported a positive association between pregnancy complications and autoimmune disease; there were insufficient studies for gestational diabetes, placental disorders, and preterm birth. Conclusions: History of certain pregnancy complications may be a novel risk factor for autoimmune disease in women. Additional high-quality research with geographically diverse data sources would be valuable.

The Chromosome 19 miRNA Cluster Guards Trophoblasts Against Overacting Innate Immunity

To maintain pregnancy health, the human placenta delicately balances protection of the developing fetus from invading pathogens with suppression of excessive inflammation that could lead to fetal and neonatal autoimmune disorders. Previous research, including our own, has shown that small RNA products of the Chromosome 19 MicroRNA Cluster (C19MC) promote viral resistance in non-trophoblastic cells. However, the role of C19MC products in placental trophoblasts remained unclear. Here, we analyzed chromatin accessibility in the C19MC enhancer and identified a previously unknown regulatory domain. Deletion of this domain silenced the expression of C19MC microRNA and Alu elements in trophoblasts. This silencing unexpectedly led to marked activation of cellular innate immune response and strikingly increased Toll-like receptor 3 (TLR3)-mediated sensitivity to poly(I:C), a viral RNA mimic. Our data suggest that C19MC non-coding RNAs interfere with endosomal TLR3 activation in trophoblasts, highlighting a previously unrecognized mechanism for hindrance of excessive innate immune activation.

Hypertensive disorders of pregnancy trends in the United States post aspirin recommendation guidelines

OBJECTIVE

To evaluate changes in the rates of hypertensive disorders of pregnancy (HDP) in the US after the publication of aspirin (ASA) recommendation guidelines by the USPSTF and ACOG.

METHODS

A population-based retrospective cohort study was performed using the US Natality database. The pre-ASA group included births between 2010-2014. The post-ASA group were births between 2016-2021. Births in 2015 were excluded. Outcomes were rates of HDP. Univariate and multivariate analyses were performed. Using the 2010-2014 HDP trend, a projected trend was calculated and compared to the actual trend across the entire cohort.

RESULTS

There were 12,127,659 births in the pre-ASA group and 17,665,217 births in the post-ASA group. The post-ASA group had a significantly higher rate of overall HDP than the pre-ASA group (7.7 % vs 4.9 %; aOR 1.58, 95 % CI [1.57-1.59]). When stratified by gestational age at delivery, the post-ASA group had a significantly lower rate of preterm HDP prior to 37 weeks (21.6 % vs 23.7 %; aOR 0.90, 95 % CI [0.89-0.91]) and preterm HDP prior to 34 weeks (6.0 % vs 7.5 %; aOR 0.79, 95 % CI [0.78-0.81]). The actual HDP trend post-ASA recommendation was higher than projected for overall HDP and preterm HDP < 37 weeks but was not different for preterm HPD < 34 weeks.

CONCLUSION

While overall HDP is increasing, the rate of preterm births complicated by HDP has been decreasing. The actual trend for the overall HDP category and the two preterm HDP categories, however, remains either higher or no different compared to the projected trend post aspirin recommendation guidelines.

Placenta at single-cell resolution in early and late preeclampsia: insights and clinical implications

Preeclampsia, one of the great obstetrical syndromes, manifests through diverse maternal and fetal complications and remains a leading contributor to adverse perinatal outcomes. In this review, we describe our work on single-cell and single-nuclei RNA sequencing to elucidate the molecular mechanisms that underlie early- and late-onset preeclampsia. Analysis of 46 cell types, encompassing approximately 90,000 cells from placental tissues collected after delivery, demonstrated cellular dysregulation in early-onset preeclampsia, whereas late-onset preeclampsia showed comparatively subtle changes. These findings were observed in all cell lines, including all types of trophoblast, lymphoid, myeloid, stromal, and endothelial cells. Key findings in early-onset preeclampsia included disrupted syncytiotrophoblast and extravillous trophoblast angiogenic signaling, characterized by an up-regulation of FLT1 and down-regulation of PGF, consistent with an angiogenic imbalance. The stromal and vascular compartments exhibited stress-induced transcriptomic shifts. Both endothelial cells and pericytes showed evidence of stress, including up-regulation of heat shock proteins and markers of apoptosis. In addition, the inflammation- and stress-responsive states were more abundant in early-onset preeclampsia than in matched controls. Inflammatory pathways were markedly up-regulated in both the maternal and fetal immune cells; for example, we observed a marked increase in pro-inflammatory cytokines, including secreted phosphoprotein 1 and C-X-C motif chemokine ligand 2 and 3. Conversely, late-onset preeclampsia retained adaptive placental features with localized dysregulation of extracellular matrix remodeling and angiogenic markers, underscoring its possible maternal cardiovascular etiology. Single-cell and single-nuclei RNA sequencing investigations of placental tissues support the proposed classification of preeclampsia into a placental dysfunction type, primarily presenting early in pregnancy, and a maternal cardiovascular maladaptation type, primarily presenting later in pregnancy, each with distinct biomarkers, risk factors, and therapeutic targets. The early-onset preeclampsia findings advocate for interventions that target angiogenic pathways, such as RNA-based therapies that target specific cells of the placenta, to modulate soluble fms-like tyrosine kinase-1 levels. In contrast, late-onset preeclampsia management may benefit from maternal cardiovascular optimization, including individualized antihypertensive and metabolic treatments. These results underscore the heterogeneity of preeclampsia, emphasizing the need for individualized diagnostic and therapeutic strategies. This molecular atlas of preeclampsia advances our understanding of the complex interplay among elements of the maternal-placental-fetal array, thereby bridging clinical phenotypes and cellular mechanisms. Future research should focus on integrating these insights into longitudinal studies to develop precision medicine approaches for preeclampsia to enhance outcomes for mothers and neonates.

Hydrogen sulfide sustains mitochondria functions via targeting mitochondria fission regulator 1 like protein to restore human cytotrophoblast invasion and migration

Hydrogen sulfide (H2S) is bioactive in mammals. Reduced H2S was observe in pregnancy complications, pre-eclampsia (PE). Our previous data demonstrated that low dose of H2S enhanced cytotrophoblast (CTB) invasion and migration via mitochondria dynamics without knowing the mechanisms. This study was designed to explore the functional regulation of CTB by mitochondrial fission regulator 1 like (MTFR1L) and the mechanisms. By studying human placenta samples and HTR-8/SVneo cell line, MTFR1L was found expressed in CTB. While MTFR1L expression was lower in PE placenta and CTB comparing with Normal pregnancy. Knockdown of MTFR1L decreased CTB invasion and migration, as well as the ATP production, while increased the mitochondria fragmentation, ROS production and mitochondria membrane potential indicating MTFR1L was key regulator of mitochondria. The posttranslational modulation analysis showed enhanced persulfidation of MTFR1L on cystine 222 and 230 by H2S. Mutations of MTFR1LC222/C230 suppressed ATP production, CTB invasion, migration, and increased mitochondria fragmentation, ROS production and mitochondria membrane potential. The present study showed the functional MTFR1L received endogenous CBS/H2S regulation. MTFR1LC222/230 persulfidation by H2S maintained mitochondria morphology and functions thus restored CTB invasion and migration. These findings established a new regulatory pathway for CTB invasion and migration, and provided new targets for PE treatment.

Patterns of health service use before and after diagnosis of endometriosis: a data linkage prospective cohort study

STUDY QUESTION

What are the patterns of health service use (HSU) before and after endometriosis diagnosis?

SUMMARY ANSWER

Women with endometriosis had higher rates of visits to general practitioners (GPs), specialists, and diagnostic imaging before and after diagnosis compared to those without the condition; however, after diagnosis, their visits to GPs and specialists other than obstetricians/gynaecologists decreased compared to before, while visits to obstetricians/gynaecologists and use of diagnostic imaging increased.

WHAT IS KNOWN ALREADY

Women with endometriosis have higher rates of healthcare use compared to those without the condition; however, no longitudinal study has examined patterns of HSU over a prolonged period before and after diagnosis.

STUDY DESIGN, SIZE, DURATION

The Australian Longitudinal Study on Women's Health linked to a national administrative health record. A total of 30 473 women, born in 1973-1978 and 1989-1995, from two cohorts with data collected from 1996 to 2021, as online or postal questionnaires.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Women with endometriosis were identified using the self-report surveys and their administrative health records. A control group of women without endometriosis was randomly selected and age-matched with women with endometriosis. The final sample included 9545 women from the 1973-1978 cohort (1909 cases, 7636 controls) and 7510 from the 1989-1995 cohort (1502 cases, 6008 controls). Women's HSU was assessed using the Medicare Benefits Schedule database. A random intercept zero-inflated negative binomial model was used to compare outcomes between cases and controls, addressing skewed data, over-dispersion, and excess zeros.

MAIN RESULTS AND THE ROLE OF CHANCE

In both cohorts, women with endometriosis had a higher level of HSU, both before and after diagnosis, compared with those without the condition. For the 1973-1978 cohort, women with endometriosis had a higher rate of visits to GPs before and after diagnosis (adjusted incidence rate ratio: 1.19, 95% CI 1.14, 1.23 and 1.24, 95% CI 1.19, 1.30, respectively), specialists other than obstetricians/gynaecologists (1.50, 95% CI 1.40, 1.61, and 1.36, 95% CI 1.27, 1.46), and for diagnostic imaging (1.15, 95% CI 1.10, 1.21, and 1.20, 95% CI 1.15, 1.26). The average number of these visits remained consistent in the early years, peaked around 3 years before diagnosis, and then partly declined post-diagnosis, to later stabilize at a higher level than those without the condition. Following the diagnosis, women with endometriosis had a higher number of visits to obstetricians/gynaecologists (1.11, 95% CI 1.05, 1.17) than their matched controls, with a marked increase in the first 6 years post-diagnosis, but gradually returned to same levels as the control group. After diagnosis, women with endometriosis had a lower rate of visits to GPs (0.95, 95% CI 0.93, 0.98) and specialists other than obstetricians/gynaecologists (0.88, 95% CI 0.82, 0.93) compared to before their diagnosis, while they had a higher rate of visits to obstetricians/gynaecologists (1.09, 95% CI 1.01, 1.18) and diagnostic imaging (1.07, 95% CI 1.01, 1.14). Similar patterns of HSU were observed in the 1989-1995 cohort, regardless of whether surgically confirmed or clinically suspected cases of endometriosis were used, though the evidence for changes in specific HSU before and after diagnosis was weaker.

LIMITATIONS, REASONS FOR CAUTION

Approximately half of the women with endometriosis were clinically suspected cases without laparoscopic confirmation, which may result in an overestimation of prevalence and introduce the risk of misdiagnosis, potentially influencing clinical management and research findings.

WIDER IMPLICATIONS OF THE FINDINGS

The continued high level of HSU among women with endometriosis, even over a decade after diagnosis, suggests that they have substantially greater healthcare needs than other women. The distinct patterns of the use of healthcare in the years before and after endometriosis diagnosis can support efforts to improve diagnosis, management, and treatment outcomes for patients and to reduce healthcare costs.

STUDY FUNDING/COMPETING INTEREST(S)

The Australian Longitudinal Study on Women's Health is funded by the Australian Government Department of Health and Aged Care. G.D.M. and G.M. are Australian National Health and Medical Research Council Leadership Fellows (GNT2009577 and GNT1177194). D.G.G. was funded by MRFF EndoAIMM (RFEHP100126). Funding sources had no role in the study design, data analysis, interpretation, or manuscript writing. The authors have no conflict of interest to declare.

TRIAL REGISTRATION NUMBER

N/A.

Soluble fms-like tyrosine kinase-1/placental growth factor ratio at 36 weeks' gestation: association with spontaneous onset of labor and intrapartum fetal compromise in low-risk pregnancies

BACKGROUND

Previous evidence showed that placental dysfunction triggers spontaneous preterm or term births and intrapartum fetal compromise and often requires urgent delivery, thereby exposing both the fetus and the mother to significant risks. Predicting spontaneous labor onset and intrapartum fetal compromise could improve obstetrical management and outcomes, but this is currently difficult, particularly in low-risk populations.

OBJECTIVE

The objective of this study was to examine whether placental dysfunction, as assessed at 36 weeks' gestation by the soluble fms-like tyrosine kinase-1 to placental growth factor ratio, is associated with the interval to spontaneous onset of labor and intrapartum fetal compromise that requires cesarean delivery in a routinely examined population.

STUDY DESIGN

This was a retrospective analysis of prospectively collected data of women with singleton pregnancies who underwent routine assessment at 35+0 to 36+6 weeks' gestation at the King's College Hospital (London, England). Using a general linear model, the study examined the outcomes related to the soluble fms-like tyrosine kinase-1/placental growth factor ratio, including the time interval from testing to spontaneous onset of labor and the subsequent rate of fetal compromise that required a cesarean delivery. Patients who underwent induction of labor or prelabor cesarean deliveries were excluded from the study. Competing risks regression and Cox regression models were used to estimate the cumulative incidence and the risk of the outcomes of interest.

RESULTS

In the screened population of 45,375 patients, 23,831 (52.5%) had spontaneous onset of labor and were included in the analysis. Cases with an soluble fms-like tyrosine kinase-1/placental growth factor ratio >50 delivered about 1 week earlier than those with a ratio of ≤50 (39.2 vs 40.0 weeks' gestation; P<.001). The general linear model showed that a larger soluble fms-like tyrosine kinase-1/placental growth factor ratio was associated with earlier spontaneous onset of labor (P<.001), particularly among multiparous women. The soluble fms-like tyrosine kinase-1/placental growth factor ratio was significantly associated, as expected, with cases of preeclampsia and advanced maternal age. The cumulative incidence of spontaneous onset of labor was significantly higher in cases with an soluble fms-like tyrosine kinase-1/placental growth factor ratio >50 than in those with a ratio 50 (P<.001). Cox regression showed that the risk for spontaneous onset of labor increased with an soluble fms-like tyrosine kinase-1/placental growth factor ratio >50 (hazard ratio, 1.424; 95% confidence interval, 1.253-1.618; P<.001) and, as expected, the risk was mitigated over time from when the soluble fms-like tyrosine kinase-1/placental growth factor ratio was measured to spontaneous labor onset (P<.001). Cases with intrapartum fetal compromise had a higher mean soluble fms-like tyrosine kinase-1/placental growth factor ratio than those without intrapartum fetal compromise (21.79 vs 17.67; P<.001). Qualitative addition of fetal compromise to the general linear model showed a higher soluble fms-like tyrosine kinase-1/placental growth factor ratio in cases with fetal compromise than in those without fetal compromise (P=.014). Competing risks regression showed a positive dose-response effect for fetal compromise with increasing soluble fms-like tyrosine kinase-1/placental growth factor ratios (P<.001). Above and below the optimal cutoff of 50, the quoted cumulative incidences were 6.7% and 4.7%, respectively (P<.001). The effect of the soluble fms-like tyrosine kinase-1/placental growth factor ratio remained significant even after adjusting for preeclampsia, which is a well-known major risk factor for fetal compromise. Finally, the proportion of cases with intrapartum fetal compromise who had an soluble fms-like tyrosine kinase-1/placental growth factor ratio >50 decreased from 35% to 0% with advancing gestation.

CONCLUSION

This study showed that an increased soluble fms-like tyrosine kinase-1/placental growth factor ratio at 36 weeks' gestation is associated with an earlier gestational age at spontaneous onset of labor and higher rates of intrapartum fetal compromise. There are 2 major implications, namely an soluble fms-like tyrosine kinase-1/placental growth factor ratio >50 indicates imminent labor onset with about a 40% mean risk increase and immediate clinical translation for term pregnancy monitoring. In addition, an increased soluble fms-like tyrosine kinase-1/placental growth factor ratio increases the risk for intrapartum fetal compromise, although outcome variability indicates reassessment within multimarker models.

A Narrative Review on the Effect of Valproic Acid on the Placenta

BACKGROUND

Valproic acid (VPA) is an antiepileptic and mood-stabilizing drug with well-established teratogenic risks when taken during pregnancy. While its harmful effects on fetal development are well known, less attention has been given to its impact on placental development and function, despite the placenta's critical role in pregnancy.

AIM

This narrative review examines how VPA exposure affects placental growth, morphology, nutrient transport, and epigenetic modifications. It also considers whether placental dysfunction may contribute VPA's teratogenic effects.

RESULTS

Evidence suggests that VPA disrupts placental structure and growth, alters the expression of nutrient transporters, such as those for folate, glucose, and amino acids, and modifies the placental epigenome, including globally decreased DNA methylation and increased histone acetylation.

DISCUSSION

It is hypothesized that these epigenetic changes may influence chromatin remodelling and trophoblast gene expression, though this connection has not been fully established. Such epigenetic dysregulation may result in aberrant gene expression that underlies the structural and functional impairments observed in the placenta, potentially compromising its ability to support fetal development and contributing to VPA's teratogenic effects. Findings across studies, however, are inconsistent, varying with dose, timing of exposure, and model system. Furthermore, there is a lack of research examining sex-specific differences in placental responses to VPA, despite evidence that male and female placentas exhibit distinct growth patterns, gene expression profiles, and susceptibilities to environmental insults.

CONCLUSION

Addressing these knowledge gaps through targeted research will improve our understanding of how VPA affects the placenta and its role in teratogenesis.

In vitro differentiation of macaque extravillous trophoblasts in a low oxygen environment

INTRODUCTION

Early primate placental development occurs within a low oxygen (O2) environment, whereas in vitro differentiation of trophoblasts is performed at supraphysiologic O2 levels. Macaque trophoblast stem cells (TSCs) are capable of differentiation to extravillous trophoblasts (EVTs) in vitro, yet the morphological heterogeneity observed across cells lines necessitates evaluation of optimal culture conditions. Our objectives were to determine the impact of oxygen on the in vitro differentiation of macaque TSCs and to refine the molecular characterization of TSC-differentiated EVTs.

METHODS

Macaque TSCs were differentiated to EVTs in either 20% or 5% O2. Gene and protein expression profiles were compared between TSCs and EVTs and between differentiation conditions. Immunohistochemical analysis was performed on early gestation macaque placental tissues to assess in vivo expression of Ki-67, NCAM1 and monkey chorionic gonadotropin (mCG).

RESULTS

EVTs differentiated in 20% O2 had significantly higher expression of CGA, CGB and NOTCH2 and decreased HIF1A expression compared to those cultured in 5% O2. Regardless of oxygen condition, nearly all EVTs expressed NCAM1 and Mamu-AG, the macaque-specific homolog of human EVT marker HLA-G. In vivo placental expression of NCAM1 was restricted to EVTs within the trophoblastic shell and endovasculature, revealing a macaque EVT marker within the placenta.

DISCUSSION

Reduced oxygen minimally impacted macaque EVT differentiation in vitro. Elevated expression of the endovascular EVT marker NOTCH2 potentially suggests that 20% O2 supported differentiation of more mature EVTs. Altogether, a standard 20% O2 environment supports macaque EVT differentiation in vitro and the results further validate the identity of macaque TSC-differentiated EVTs.

Clinicopathologic correlation and interdependence of basic patterns of placental injury

Placental lesions rarely occur in isolation and placental lesion multiplicity is associated with poorer pregnancy outcome than that of isolated lesions. As little is known about mutual relations of various patterns of placental injury simultaneously occurring in the same placentas, particularly in relation to gestational age, this retrospective observational analysis was undertaken to study those in a population of 2486 cases of the second half high-risk pregnancy dominated by fetal congenital anomalies. To this end, 23 independent clinical and 48 placental phenotypes were statistically compared among 6 basic patterns of placental injury: Group 1: acute inflammation, Group 2: chronic inflammation, Group 3: maternal vascular malperfusion, Group 4: fetal vascular malperfusion, large vessel, Group 5: fetal vascular malperfusion, distal villous, and Group 6: shallow placental implantation. All cases had E cadherin/CD34 immunostaining performed for the diagnosis of recent fetal vascular malperfusion. There was a significant overlap among the studied patterns and lesions of placental injury. Placental distal villous fetal vascular malperfusion and acute inflammation was most frequently statistically significantly associated with abnormal clinical conditions, while lesions of distal villous fetal vascular malperfusion and maternal vascular malperfusion with other placental lesions/patterns of injury. The double immunostaining was responsible for the fetal vascular malperfusion being the most common type of placental injury in this population of placentas. The acute inflammation best correlated with clinical condition in preterm pregnancy and distal villous fetal vascular malperfusion at term. Maternal vascular malperfusion plus the above two patterns of placental injury correlated best with other placental phenotypes in mid third trimester.

Longitudinal Placental Blood Volume Measurements in Zika-Infected Rhesus Macaques Using Ferumoxytol Enhanced MRI

Introduction

Measures of maternal fractional blood volume (mFBV) in the placenta holds potential to diagnose placental vasculature deficiencies. However, methods for quantitative mapping of blood volume are challenging to implement for clinical placenta evaluation. As a preliminary step towards human applications, this study assesses the feasibility of blood volume measurements using ferumoxytol enhanced variable flip angle (VFA) T1-mapping in Zika-infected rhesus macaques.

Methods

Seven pregnant rhesus macaques were imaged longitudinally at up to 3 timepoints across gestation (days 64.5±1.9, 100.8±3.9, and 145.3±1.8), corresponding to first, second, and third pregnancy trimester of the rhesus. Four animals received a Zika virus (ZIKV) injection into the amniotic fluid, while three control rhesus macaques received a saline injection. T1-weighted spoiled gradient echo sequences at four flip angles (2°, 6°, 10°, 14°) were used for quantitative mFBV assessment derived from pre- and post-contrast T1 mapping using ferumoxytol. Image quality assessment and segmentation assessment was performed on the full 3D coverage. Placental histopathology for all animals was analyzed by a professional pathologist with over 15 years of experience.

Results

All scans were successfully acquired and analyzed with no significant motion artifacts. 3D mFBV maps show regional heterogeneities within slices. FBV and total placental blood volume has an increasing trend with gestation.

Discussion

This study shows feasibilities to measure mFBV in non-human primates using ferumoxytol enhanced VFA T1-mapping.

How can artificial intelligence models advance placental biology?

The placenta is a vital organ that supports the developing fetus during pregnancy. Histologic examination of the placenta can reveal abnormalities in morphology and structure that impact placental function. Machine learning (ML) models have been successfully developed for digital pathology, leveraging rich image datasets from human tissue. ML models can be advantageous to placenta researchers, either by supplementing pathologist expertise or providing knowledge to inform future hypothesis generation. Research projects fall into several categories: Cell classification methods have been introduced to the placental disc and membranes. Cell classification is useful as a "bottom up" approach to characterizing tissue, using smaller image inputs than at a tissue region or whole slide level. Classification of normal tissues, cells, and development can identify pathologies that deviate. Several studies have identified pathologies within the great obstetric syndromes or placental inflammation. These studies often use mechanisms to aggregate findings from small images patches up to the whole slide level. Digital pathology slides are rich with data that inform our knowledge of placental function and disease - while many articles focus on model design and performance, the features extracted can add valuable biological and clinical knowledge to the field.

Exosomes secreted from amniotic mesenchymal stem cells modify trophoblast activities by delivering miR-18a-5p and regulating HRK-p53 interaction

BACKGROUND

Amniotic mesenchymal stem cells (AMSCs) have been demonstrated as effective in tissue repair and regeneration. Trophoblast dysfunction is associated with several types of pregnancy complications. The aim of this study is to investigate the effects of AMSCs on the biological activities of human trophoblasts, as well as their molecular mechanisms.

METHODS

Exosomes were isolated from AMSC supernatants, and characterized and quantified by transmission electron microscopy, nanoparticle tracking analysis and Western blotting assay. Immunofluorescence assay was performed to detect the uptake of AMSCs-derived exomes (AMSC-Exos) by human trophoblasts. Human trophoblasts were subjected to transcriptome analysis after being cocultured with AMSC-Exos. Lentiviral transfection was performed to construct the human trophoblast cell lines with stable HRK knockdown or overexpression. Immunohistochemistry was used to detect the HRK expression in preeclampsia (PE) patients. CCK8 and Transwell assays were, respectively, used to detect the trophoblast proliferation and migration. TUNEL flow cytometry assay was used to detect the apoptosis in trophoblasts. Quantitative real-time (qRT) PCR and Western blotting assays were used to detect the mRNA and protein levels of the genes. Dual luciferase reporter assays were used to detect the changes in gene-transcript levels.

RESULTS

AMSC-Exos could be absorbed by human trophoblasts. Transcriptome analysis showed that HRK was significantly reduced in human trophoblasts cocultured with AMSC-Exos. HRK inhibited cell proliferation and migration in human trophoblasts and promoted their apoptosis via p53 upregulation. miR-18a-5p, present at high levels in AMSC-Exos, improved trophoblast proliferation and migration, and inhibited their apoptosis by inhibiting the HRK expression.

CONCLUSION

miR-18a-5p present in AMSC-Exos could be absorbed by trophoblasts, in turn, improved their proliferation and migration, and inhibited their apoptosis by HRK downregulation.

Association of maternal calprotectin plasma levels with abruption placenta

OBJECTIVE

The aim of this study was to investigate the relationship between placental abruption and maternal plasma calprotectin levels.

MATERIALS AND METHODS

This prospective study included 3865 pregnant women aged 24 weeks' gestation and older who were admitted to Etlik Zübeyde Hanım Women's Health Training and Research Hospital between January 2021 and January 2024. Calprotectin levels were prospectively studied in 33 pregnant women with placental abruption and compared with 48 healthy pregnant women matched for age, parity, body mass index (BMI) and week of gestation. Pregnant women with preeclampsia, gestational diabetes, chorioamnionitis, premature rupture of membranes, preterm labor, corticosteroid use within 7 days, cholestasis, fetal growth restriction, fetal anomalies, systemic infections and multiple pregnancies were excluded from the study. The calprotectin concentration in serum was measured with a Rayto Microplate Reader RT 2100 C (Rayto) using an immunoassay method at 450 wavelengths.

RESULTS

There was no difference between the groups regarding maternal age, gravidity, parity and BMI. Calprotectin levels were significantly higher in the placental abruption group (p < 0.001). The optimal cutoff value for calprotectin was 91.95 ng/ml (sensitivity 66.67%, specificity 89.58%, the area under the curve (AUC) 0.763, 95% confidence interval 0.649-0.876, and p < 0.001).

CONCLUSION

The results obtained in the present study revealed an association between placental abruption and higher maternal serum calprotectin levels.

Impact of maternal smoking and secondhand smoke exposure during singleton pregnancy on placental abruption: analysis of a prospective cohort study (the Japan Environment and Children's Study)

OBJECTIVES

This study aimed to investigate the association and population-attributable fraction (PAF) of maternal smoking and secondhand smoke (SHS) exposure during pregnancy with placental abruption.

DESIGN

Prospective cohort study.

SETTING

15 regional centres in Japan.

PARTICIPANTS

Pregnant women registered between January 2011 and March 2014 from the Japan Environment and Children's Study.

OUTCOME MEASURES

Data were transcribed from medical records and two self-administered questionnaires. The outcome measure was the incidence of placental abruption. Maternal smoking exposure during pregnancy was categorised based on the number of cigarettes smoked (≤10 or ≥11 cigarettes per day). SHS exposure during pregnancy was evaluated by frequency and duration (almost never or never, 1-3 days/week and/or <1 hour/day and 4-7 days/week and ≥1 hour/day). A modified Poisson regression model, adjusted for known placental abruption risk factors, calculated the risk ratio (RR) and PAF for placental abruption with a 95% Cl.

RESULTS

Of the 81 974 eligible pregnant women, pregnant women smoking ≥11 cigarettes/day during pregnancy had a significantly higher risk of placental abruption. The adjusted RR (aRR) was 2.21 (95% CI 1.21 to 4.06), and the adjusted PAF (aPAF) was 1.90% (95% CI 0.09 to 3.71%). Pregnant women among never-smokers with SHS exposure of 4-7 days/week and ≥1 hour/day had a significantly higher risk (aRR: 2.34, 95% CI 1.29 to 4.28), and the aPAF was 1.89% (95% CI -0.05 to 3.83). Additionally, pregnant women among those who smoked during pregnancy with similar SHS exposure had a significantly higher risk (aRR: 2.21, 95% CI 1.30 to 3.76), with the aPAF of 2.29% (95% CI 0.11 to 4.48).

CONCLUSIONS

Maternal smoking and SHS exposure during pregnancy significantly contribute to the risk of placental abruption in Japan. Therefore, preventive interventions and measures to reduce exposure are required to prevent placental abruption.

Characteristics of maternal-placental vascular malperfusion and its correlation with neonatal adverse outcomes

INTRODUCTION

Fetal growth restriction (FGR) is the failure of fetal growth to attain inherent genetic potential owing to a diverse array of factors. Limited studies have investigated the correlation between varying levels of maternal-placental vascular malperfusion (MVM)-type FGR and adverse neonatal outcomes. Thus, we sought to explore the maternal-fetal characteristics of different degrees of MVM-type FGR and their correlation with adverse neonatal outcomes.

METHODS

We collected all cases of FGR from 2018 to 2023 and observed the pregnancy, delivery, and newborn characteristics of FGR cases managed by a fetal medical center. General information, clinical examinations, and neonatal outcomes were recorded. Placental lesions were sampled and classified according to the 2016 Amsterdam standard, then divided into two groups based on MVM level: low-grade and high-grade.

RESULTS

The high-grade MVM-type FGR group (30/94) had a higher prevalence of pregnant mothers with diabetes mellitus (P＝0.022) and hypertension (P＝0.013), higher incidence of abnormal umbilical artery pulsatility index (UA-PI) (P＝0.022) and uterine artery pulsatility index (UtA-PI) (P < 0.001), higher incidence of incomplete distal villus development (P＝0.027) and placental vascular disease (P＝0.008), higher incidence of cerebral hemorrhage (P＝0.006) and poor outcomes (P＝0.04), lower fetal weight (P＝0.026), and longer hospital stays for newborns (P＝0.018). Logistic regression analysis showed that body mass index (P＝0.04), diabetes (P＝0.033), assisted reproduction (P＝0.048), pathological placental villus overmaturity (P＝0.033) High-grade MVM (P＝0.014) were independent risk factors for adverse neonatal outcomes, fetal birth weight (P＝0.004) is an independent protective factor.

DISCUSSION

High-grade MVM FGR is associated with the incidence rate of adverse neonatal outcomes, with a series of differences in the pre-pregnancy state, clinical auxiliary examination, and pathological characteristics compared with low grade MVM. Simultaneously, we found five independent risk factors and one protective factor that led to adverse neonatal outcomes in MVM group.

Maternal vascular dysfunction in gestational diabetes is associated with birth of small neonates

AIMS

The study aimed to evaluate maternal hemodynamic and vascular changes in women with small-for-gestational age(SGA) and large-for-gestational age(LGA) fetuses in the presence and absence of gestational diabetes mellitus(GDM).

MATERIALS

Women at 35+0 to 36+6 weeks' gestation with and without GDM were included. Maternal demographics, ultrasound for fetal growth, Doppler studies of uterine and ophthalmic arteries, carotid-femoral pulse-wave velocity(PWV), augmentation index, cardiac output, and total peripheral resistance(TPR) were recorded. Multinomial logistic regression was used.

RESULTS

Of 11,132 women, 1,228(11.0%) developed GDM. In GDM pregnancies, 158(12.8%) delivered SGA and 136(11.1%) delivered LGA neonates, while non-GDM pregnancies had 1,051(10.6%) SGA and 806(8.1%) LGA neonates. In GDM and non-GDM women, SGA groups had the highest uterine artery pulsatility index(PI) percentiles, PWV and ophthalmic artery peak systolic velocity ratio. PWV was higher in the GDM SGA group compared to non-GDM SGA group. Cardiac output was lower in SGA groups when compared to the AGA group. In women with GDM, TPR, ophthalmic artery PSV ratio and uterine artery PI percentile had a positive association with the development of SGA.

CONCLUSIONS

Women with GDM and vascular dysfunction have higher risk to deliver SGA neonates. Maternal hemodynamic and vascular maladaptation could potentially explain the development of SGA in women with GDM.

Vascular Placental Pathology and Cardiac Structure in Stillborn Fetuses

OBJECTIVE

 Adverse pregnancy outcomes, including preterm birth and preeclampsia, are associated with worse cardiovascular outcomes for offspring. Examination of the placenta is important for understanding how the prenatal period shapes long-term cardiovascular health. We sought to investigate the association between placental vascular malperfusion and fetal cardiac structure.

STUDY DESIGN

 Data obtained from the Stillbirth Collaborative Research Network included stillbirths with placental pathology and autopsy. Stillbirths were classified in two ways: based on the severity of placental maternal vascular malperfusion (MVM) and based on the cause of death (MVM, fetal vascular malperfusion [FVM], or acute infection/controls). Organ weight and heart measures were standardized by gestational age (GA) and compared across groups.

RESULTS

 We included 329 stillbirths in the analysis by MVM severity and 76 in the analysis by cause of death (COD). While z-scores for most organ weights/heart measures were smaller when COD was attributed to MVM as compared with FVM or controls, heart weight and brain weight z-scores did not differ by COD (p > 0.05). In analyses accounting for body size, the difference between heart and body weight z-score was -0.05 (standard deviation [SD]: 0.53) among those with MVM as a COD and -0.20 (SD: 0.95) among those with severe MVM. Right and left ventricle thicknesses and tricuspid, pulmonary, mitral, and aortic valve circumferences were consistently as expected or larger than expected for GA and body weight. In the analysis investigating the severity of MVM, those with the most severe MVM had heart measures that were as expected or larger than expected for body weight while those with only mild to moderate MVM had heart measures that were generally small relative to body weight.

CONCLUSION

 When assessed as COD or based on severity, MVM was associated with heart measures that were as expected or larger than expected for GA and body weight, indicating possible heart sparing.

KEY POINTS

· Fetal deaths with MVM show smaller organ weights.. · Heart weight sparing is seen with fetal death attributed to MVM.. · Heart weight sparing is more pronounced with severe MVM..

Ischemic Placental Disease: Epidemiology and Impact on Maternal and Offspring Health Along the Life Course

Ischemic placental disease (IPD) is a constellation of obstetrical complications that include preeclampsia, placental abruption, and fetal growth restriction and affects 12% to 15% of pregnancies. The unifying pathophysiological mechanism that precedes all 3 complications is uteroplacental ischemia as a consequence of inadequate (or failure of) physiological transformation of the maternal uterine spiral arteries, endothelial cell dysfunction, and increased oxidative stress. This review summarizes the IPD literature, focusing on the epidemiology and risk factors, the effects of IPD on short and long-term maternal complications, and the association of IPD with perinatal, childhood, and long-term complications in offspring.

Aspirin dosage for preeclampsia prophylaxis: an argument for 81-mg dosing

Research conducted over the past few decades has shown that low-dose aspirin can effectively reduce the risk of developing preeclampsia. Consequently, numerous prominent organizations have adopted the recommendation to use low-dose aspirin during pregnancy to prevent preeclampsia. However, the optimal dosage of low-dose aspirin (81mg versus 162mg) remains a subject of debate. Currently, there is insufficient high-quality data to justify the use of a higher dosage of low-dose aspirin. In this review, we review the existing evidence that supports the continued use of 81mg of aspirin over a higher dose and emphasize the need for high-quality research to alter current recommendations.

Universal First-Trimester Screening Biomarkers for Diagnosis of Preeclampsia and Placenta Accreta Spectrum

BACKGROUND

Disruptions in epigenetic mechanisms regulating placentation, particularly imbalances in the levels of small non-coding RNAs, contribute to various pregnancy complications, including preeclampsia (PE) and placenta accreta spectrum (PAS). Given that abnormal trophoblast differentiation, invasiveness, and angiogenesis-reduced in PE and excessive in PAS-are central to the pathogenesis of these conditions, this study aimed to identify universal circulating piRNAs and their targets.

METHODS

Small RNA deep sequencing, quantitative reverse transcription combined with real-time polymerase chain reaction, magnetic bead-based multiplex immunoassay, ELISA, and Western blotting were employed to quantify circulating piRNAs and proteins in the blood serum of pregnant women during the 11th-14th weeks of gestation.

RESULTS

Statistically significant negative correlations were identified between PE- and PAS-associated piRNAs (hsa_piR_019122, hsa_piR_020497, hsa_piR_019949, and piR_019675) and several molecules, including Endoglin, IL-18, VEGF-A, VEGF-C, Angiopoietin-2, sFASL, HB-EGF, TGFα, and Clusterin. These molecules are involved in processes such as angiogenesis, inflammation, the epithelial-mesenchymal transition, cell proliferation, adhesion, and apoptosis. A first-trimester pregnancy screening algorithm was developed using logistic regression models based on Clusterin concentration and the levels of hsa_piR_020497, hsa_piR_019949, piR_019675, and hsa_piR_019122.

CONCLUSIONS

The proposed screening tool for early pregnancy monitoring may enable the prediction of PE or PAS in the first trimester, allowing timely interventions to reduce maternal and perinatal morbidity and mortality.

Development of a spontaneous preterm birth predictive model using a panel of serum protein biomarkers for early pregnant women: A nested case-control study

OBJECTIVE

To develop a model based on maternal serum liquid chromatography tandem mass spectrometry (LC-MS/MS) proteins to predict spontaneous preterm birth (sPTB).

METHODS

This nested case-control study used the data from a cohort of 2053 women in China from July 1, 2018, to January 31, 2019. In total, 110 singleton pregnancies at 11-13+6 weeks of pregnancy were used for model development and internal validation. A total of 72 pregnancies at 20-32 weeks from an additional cohort of 2167 women were used to evaluate the scalability of the model. Maternal serum samples were analyzed by LC-MS/MS, and a predictive model was developed using machine learning algorithms.

RESULTS

A novel predictive panel with four proteins, including soluble fms-like tyrosine kinase-1, matrix metalloproteinase 8, ceruloplasmin, and sex-hormone-binding globulin, was developed. The optimal model of logistic regression had an AUC of 0.934, with additional prediction of sPTB in second and third trimester (AUC = 0.868).

CONCLUSION

First-trimester modeling based on maternal serum LC-MS/MS identifies pregnant women at risk of sPTB, which may provide utility in identifying women at risk at an early stage of pregnancy before clinical presentation to allow for earlier intervention.

The relationship between abnormal fetoplacental Dopplers, angiogenic markers of placental dysfunction and adverse perinatal outcomes in diabetic pregnancies with small fetuses - A prospective study

INTRODUCTION

The aim of this study was to evaluate differences in circulating maternal placental biomarkers and fetoplacental Dopplers in women with diabetes mellitus in pregnancy (DIP) with prenatally identified small fetuses (defined as <20th centile for gestational age) compared to women with small fetuses without DIP.

METHODS

This was a prospective cohort study of women with DIP with small infants compared to a non-diabetic cohort with similarly small fetuses. Multivariable logistic regression was used to evaluate the effect of DIP on placental biomarkers, fetoplacental Dopplers, and adverse perinatal outcomes.

RESULTS

There were 447 pregnancies in this study - 117 (26.2 %) had DIP and 330 (73.8 %) did not have diabetes. Of the DIP cohort, 57 (48.7 %) had early-onset and 27 (23.1 %) had late-onset FGR. Higher rates of low PlGF levels<100 ng/L (42.1 % vs. 25.7 %,p = 0.002), high sFlt-1/PlGF ratio (39.6 % vs. 25.4 %,p = 0.006), low MCA PI < 5th centile at recruitment (18.8 % vs. 7.6 %,p < 0.001, OR 2.37 95%CI 1.25, 4.46,p = 0.008), abnormal UA Doppler before delivery (OR 1.63 95%CI 1.00, 2.66,p = 0.048) were seen in the DIP cohort. DIP was associated with higher rates of emergency cesarean section (43.6 % vs. 26.7 %,p = 0.001) and lower birthweight (2300 (1558, 2610g) vs. 2447 (2050, 2690g),p = 0.003). The odds of early FGR (OR 1.90 95%CI 1.20, 2.98,p = 0.006), PTB<37 weeks (OR 1.66 95%CI 1.02, 2.70,p = 0.039), PTB<34 weeks' gestation (OR 3.00 95%CI 1.51, 5.96,p = 0.002), composite non-neurological neonatal morbidity (OR 1.86 95%CI 1.04, 3.33,p = 0.037), and hypoglycemia (OR 3.69 95%CI 1.59, 8.54,p = 0.002) were significantly higher in DIP.

CONCLUSIONS

DIP is associated with increased risks of early-onset FGR, PTB, composite severe non-neurological neonatal morbidity, and neonatal hypoglycemia in women with small infants. DIP was significantly associated with increased odds of MCA PI < 5th centile at diagnosis and abnormal UA Doppler before birth.

Multi-omics-based mapping of decidualization resistance in patients with a history of severe preeclampsia

Endometrial decidualization resistance (DR) is implicated in various gynecological and obstetric conditions. Here, using a multi-omic strategy, we unraveled the cellular and molecular characteristics of DR in patients who have suffered severe preeclampsia (sPE). Morphological analysis unveiled significant glandular anatomical abnormalities, confirmed histologically and quantified by the digitization of hematoxylin and eosin-stained tissue sections. Single-cell RNA sequencing (scRNA-seq) of endometrial samples from patients with sPE (n = 11) and controls (n = 12) revealed sPE-associated shifts in cell composition, manifesting as a stromal mosaic state characterized by proliferative stromal cells (MMP11 and SFRP4) alongside IGFBP1+ decidualized cells, with concurrent epithelial mosaicism and a dearth of epithelial-stromal transition associated with decidualization. Cell-cell communication network mapping underscored aberrant crosstalk among specific cell types, implicating crucial pathways such as endoglin, WNT and SPP1. Spatial transcriptomics in a replication cohort validated DR-associated features. Laser capture microdissection/mass spectrometry in a second replication cohort corroborated several scRNA-seq findings, notably the absence of stromal to epithelial transition at a pathway level, indicating a disrupted response to steroid hormones, particularly estrogens. These insights shed light on potential molecular mechanisms underpinning DR pathogenesis in the context of sPE.

IGSF8 impairs migration and invasion of trophoblast cells and angiogenesis in preeclampsia

Insufficient trophoblast cell infiltration is implicated in the progression of preeclampsia (PE). The immunoglobulin superfamily member 8 (IGSF8) has been shown to promote cell migration, invasion, and epithelial mesenchymal transition (EMT). However, the specific impact of IGSF8 on trophoblast cells in PE has not been definitively demonstrated. To address this, placental tissues from PE patients and normal subjects was collected. A PE-like rat model was established by administering L-NAME (60 mg/kg) intragastrically to pregnant rats from the 10th to the 19th day of gestation. Knockdown and overexpression plasmids of IGSF8 were transfected into JEG-3 cells for further experiments. Clinical samples indicated impaired spiral artery remodeling, and high IGSF8 expression in the placental tissues of PE patients. PE rats exhibited increased mean arterial pressure, elevated 24-h urine protein levels, higher abortion rates, and decreased placental and fetal weight compared to rats of sham group. Failure of physiological transformation of spiral arteries was observed in PE rats, along with increased IGSF8 expression. IGSF8 overexpression inhibited JEG-3 cell migration, invasion and EMT, as well as reduced release of VEGF in JEG-3 cells, impairing HUVEC tube formation. mRNA-sequencing analysis of JEG-3 cells transfected with shIGSF8 showed differentially expressed genes related to angiogenesis, and mesenchymal cell differentiation, with IGSF8 knockdown being associated with the activation of pathways involved in blood vessel development and cell migration. Overall, this study suggests that IGSF8 plays a role in the development of PE and provides new insights for potential treatments.

The role of 1-Deoxysphingolipids and Polyamines in the pathogenesis of placental syndrome

BACKGROUND

Placental syndrome, mainly composed of preeclampsia and fetal growth restriction, has an impact on the health of mother and baby dyads. While impaired placentation is central to their pathophysiology, the underlying molecular mechanisms remain incompletely understood. This study investigates the association between placental syndrome and metabolic alterations in 1-deoxysphingolipids (1-deoxySLs) and polyamines, along with their regulatory enzymes.

METHODS

This prospective case-control study involved 26 healthy pregnant women and 17 with placental syndrome. Blood samples were collected from maternal, uterine venous, and umbilical cord veins. Levels of 1-deoxySL, spermine, and spermidine, as well as related enzymes of polyamine metabolism such as ornithine decarboxylase (ODC), spermidine/spermine N1-acetyltransferase (SSAT), polyamine oxidase (PAO), and spermine oxidase (SMO), were measured using the techniques of LC-MS and ELISA, respectively.

RESULTS

Women with placental syndrome had significantly higher levels of 1-deoxySL, spermine, and spermidine in all blood samples compared to the healthy pregnancy group. Additionally, ODC and SSAT levels were reduced significantly in the placental syndrome group, while PAO and SMO levels showed no significant differences. Strong positive correlations were found between the studied enzymes and biomolecules in healthy pregnancies, which were notably weaker in the placental syndrome group.

CONCLUSION

This study demonstrates significantly altered levels of 1-deoxySL and polyamines, with corresponding enzyme activity changes, in placental syndrome compared to healthy pregnancies. The disrupted correlations between these biomolecules suggest alterations in their metabolic pathways and potential utility as biomarkers. Further mechanistic studies are warranted to elucidate their role in placental syndrome pathophysiology.

Household Air Pollution Exposures Over Pregnancy and Maternal Blood Pressure Trajectories through 8 Years Postpartum: Evidence from the Ghana Randomized Air Pollution and Health Study (GRAPHS)

Background

Household air pollution is a major contributor to cardiovascular disease burden in women in Sub-Saharan Africa. However, little is known about exposures during pregnancy or the effect of clean cooking interventions on postpartum blood pressure trajectories.

Methods

The Ghana Randomized Air Pollution and Health Study (GRAPHS) randomized 1414 non-smoking women in the first and second trimesters to liquefied petroleum gas (LPG) or improved biomass stoves - vs control (traditional three-stone open fire). Personal exposure to carbon monoxide was measured at four prenatal timepoints and three times over the first postpartum year. Participants were prospectively followed with annual resting BP measurements at 2, 4, 5, 6, 7, and 8 years postpartum. We employed linear mixed effects models to determine effect of GRAPHS interventions on postpartum BP, and to examine associations between prenatal and postnatal CO and postpartum BP.

Results

LPG intervention was associated with 3.54mmHg (95% CI -5.55, -1.53) lower change in systolic BP from enrolment through 8 years postpartum, and 2.27mmHg (95% CI -3.61, -0.93) lower change in diastolic BP from enrolment through 8 years postpartum, as compared to control. In exposure-response analysis, average prenatal CO was positively associated with change in systolic BP from enrolment (β=0.71mmHg, 95% CI 0.08, 1.30, per doubling of CO).

Conclusions

LPG cookstove intervention initiated in early pregnancy and maintained through the first postpartum year was associated with lower systolic and diastolic BP trajectories through 8 years postpartum. These findings support the need to integrate clean cooking solutions into existing antenatal care packages.

Multi-System Dysregulation in Placental Malaria Contributes to Adverse Perinatal Outcomes in Mice

Sequestration of Plasmodium parasites in the placental vasculature causes increased morbidity and mortality in pregnant compared to non-pregnant patients in malaria-endemic regions. In this study, outbred pregnant CD1 mice with semi allogeneic fetuses were infected with transgenic Plasmodium berghei or mock-inoculated by mosquito bite at either embryonic day (E) 6 (first trimester-equivalent) or 10 (second trimester-equivalent) and compared with non-pregnant females. P. berghei-infected mosquitoes had greater biting avidity for E10 dams than uninfected mosquitoes, which was not apparent for E6 dams nor non-pregnant females. Infected E10 dams had greater numbers of parasites than E6 dams in the uterus and spleen, but not in the blood or liver. While parasites were found in placentas, no parasites were present in fetuses. Maternal infection at E6 caused greater maternal morbidity, with greater rates of fetal reabsorption and stillbirths than at E10. Infection at E10 caused adverse offspring outcomes, including growth restriction. To identify possible mechanisms of adverse offspring outcomes, E10 dams were euthanized during peak parasitemia (8 days post infection), and outcomes were compared with mock-infected dams. P. berghei caused significant systemic maternal immune activation with elevated circulating lymphocytes, eosinophils, and neutrophils and splenic cytokine concentrations. P. berghei infection at E10 increased corticosterone and decreased progesterone concentrations, which could contribute to adverse perinatal outcomes through immunomodulation. There were limited changes in the maternal fecal microbiome after P. berghei infection. Mosquito bite infection of outbred dams with P. berghei causes placental malaria and provides a novel, tractable model to investigate therapeutic treatments.

Single-cell RNA sequencing identifies CXADR as a fate determinant of the placental exchange surface

The placenta is the critical interface between mother and fetus, and consequently, placental dysfunction underlies many pregnancy complications. Placental formation requires an adequate expansion of trophoblast stem and progenitor cells followed by finely tuned lineage specification events. Here, using single-cell RNA sequencing of mouse trophoblast stem cells during the earliest phases of differentiation, we identify gatekeepers of the stem cell state, notably Nicol1, and uncover unsuspected trajectories of cell lineage diversification as well as regulators of lineage entry points. We show that junctional zone precursors and precursors of one of the two syncytial layers of the mouse placental labyrinth, the Syncytiotrophoblast-I lineage, initially share similar trajectories. Importantly, our functional analysis of one such lineage precursor marker, CXADR, demonstrates that this cell surface protein regulates the differentiation dynamics between the two syncytial layers of the mouse labyrinth, ensuring the correct establishment of the placental exchange surface. Deciphering the mechanisms underlying trophoblast lineage specification will inform our understanding of human pregnancy in health and disease.

Off to a good start: The importance of the placental exchange surface - Lessons from the mouse

The role of the chorio-allantoic placenta as the critical nutrient- and oxygen-supplying organ to nourish the demands of the fetus has been well recognized. This function relies on the successful establishment of the placental feto-maternal exchange unit, or interhaemal barrier, across which all nutrients as well as waste products must pass to cross from the maternal to the fetal blood circulation, or vice versa, respectively. As a consequence, defects in the establishment of this elaborate interface lead to fetal growth retardation or even embryonic lethality, depending on the severity of the defect. Beyond this essential role, however, it has also emerged that the functionality of the feto-maternal interface dictates the proper development of specific embryonic organs, with tightest links observed to the formation of the heart. In this article, we build on the foundational strength of the mouse as experimental model in which the placental causality of embryonic defects can be genetically proven. We discuss in detail the formation of the interhaemal barrier that makes up the labyrinth layer of the murine placenta, including insights into drivers of its formation and the interdependence of the cell types that make up this essential interface, from in vivo and in vitro data using mouse trophoblast stem cells. We highlight mouse genetic tools that enable the elucidation of cause-effect relationships between defects driven by either the trophoblast cells of the placenta or by embryonic cell types. We specifically emphasize gene knockouts for which a placental causality of embryonic heart defects has been demonstrated. This in-depth perspective provides much-needed insights while highlighting remaining gaps in knowledge that are essential for gaining a better understanding of the multi-facetted roles of the placenta in setting us up for a healthy start in life well beyond nutritional support alone.

Associations between metal/metalloid exposure during pregnancy and placental growth characteristics: Findings from the Hangzhou birth cohort study II

Previous studies have suggested that metal/metalloid (hereafter referred to as metal) exposure may influence placental growth by affecting gene expression in the placenta. However, no epidemiological studies have been conducted to validate the relationships between metals exposure, placental gene expression, and placental growth at the population level. This study aims to investigate these relationships based on Hangzhou birth cohort study II (HBCS-II). Totally, 1025 participants were derived from HBCS-II. Thirteen metals levels in the placenta were measured using inductively coupled plasma mass spectrometry. Placental growth characteristics were assessed, including placental weight, chorionic disc area, placental eccentricity, and distance from cord insertion site to the nearest edge of placenta (DCIEP). The relationships between metals exposure and placental growth characteristics were examined using the elastic net model combined unpenalized linear regression model. Placental gene expression levels were analyzed through RNA sequencing and real-time polymerase chain reaction (RT-qPCR), and mediation analysis was conducted to investigate whether placental gene expression could mediate the relationship between metal exposure and placental growth. Notably, the results showed that a unite increase in Ln-transformed cadmium (Cd) levels was associated with a reduction of 16.4 g [95% confidence interval (CI): 31.2, -1.5] in placental weight, 13.9 cm2 (95%CI: 20.0, -7.8) in chorionic disc area, and 0.3 cm (95%CI: 0.55, -0.06) in DCIEP. Through RNA sequencing followed by validation, significant associations were observed between placental Cd level and increased expression of placental genes, including TNFAIP2, OLAH, FLT4, SH3PXD2A, LIMCH1, BCL6, SLCO2A1, and CPSF1. Additionally, increased placental TNFAIP2, OLAH, FLT4, SH3PXD2A and LIMCH1 expression was linked to reduced placental weight. Moreover, SH3PXD2A was associated with decreased chorionic disc area. Mediation analysis showed that placental Cd level was associated with a 12.0 g (95%CI: 23.8, -2.7) decrease in placental weight mediated through the upregulation of FTL4 gene expression. The study provides evidence of the association between placental Cd exposure and decreased placental weight, and the FLT4 gene may play a mediating role in this relationship. Future experiment studies should be performed to validate the results.

Upregulated YTHDC1 mediates trophoblastic dysfunction inducing preterm birth in ART conceptions through enhanced RPL37 translation

Assisted reproductive technology (ART) pregnancies present a higher risk of singleton preterm birth than natural pregnancies, but the underlying molecular mechanism remains largely unknown. RNA m6A modification is a key epigenetic mechanism regulating cellular function, but the role of m6A modification, especially its "reader" YTHDC1, in preterm delivery remains undefined. To delineate the role and epigenetic mechanism of m6A modification in ART preterm delivery, the effects of YTHDC1 on trophoblastic function were evaluated by CCK-8, EdU, Transwell, and flow cytometry analyses post its overexpression or knockdown. Downstream signaling pathways of YTHDC1 were investigated by RNA-seq, and targeted mRNAs were explored by RIP-seq and MeRIP-seq. Upstream transcriptional factors of YTHDC1 were determined by ChIP-seq and luciferase reporter assays. Elevated YTHDC1 was detected in human ART-conceived preterm placentas and in murine preterm placentas post estradiol (E2) exposure. In vitro experiments showed that YTHDC1 promoted trophoblastic cell proliferation and migration, but inhibited cell apoptosis. Mechanistically, E2 was proven to upregulate YTHDC1 expression via retinoid X receptor alpha (RXRA) in trophoblastic cells. Enhanced YTHDC1 expression augmented the translation of RPL37 in an m6A-dependent manner by binding to m6A-modified RPL37 mRNA and concomitantly promoted the overall translational output. Importantly, administration of siRNA targeting YTHDC1 effectively delayed the progression of preterm delivery. In conclusion, the identified E2/RXRA/YTHDC1/RPL37 axis provides new insights into the epigenetic mechanism underlying ART-associated preterm delivery. The findings offer a potential prognostic biomarker and therapeutic target for preterm delivery.

The Interplay of Molecular Factors and Morphology in Human Placental Development and Implantation

The placenta is a vital organ that supports fetal development by mediating nutrient and gas exchange, regulating immune tolerance, and maintaining hormonal balance. Its formation and function are tightly linked to the processes of embryo implantation and the establishment of a robust placental-uterine interface. Recent advances in molecular biology and histopathology have shed light on the key regulatory factors governing these processes, including trophoblast invasion, spiral artery remodeling, and the development of chorionic villi. This review integrates morphological and molecular perspectives on placental development, emphasizing the roles of cytokines, growth factors, and signaling pathways, such as VEGF and Notch signaling, in orchestrating implantation and placental formation. The intricate interplay between molecular regulation and morphological adaptations highlights the placenta's critical role as a dynamic interface in pregnancy. This review synthesizes current findings to offer clinicians and researchers a comprehensive understanding of the placenta's role in implantation, emphasizing its importance in maternal-fetal medicine. By integrating these insights, the review lays the groundwork for advancing diagnostic and therapeutic approaches that can enhance pregnancy outcomes and address related complications effectively.

Efficacy of combining aspirin with hydroxychloroquine in pregnancies at high risk for pre-eclampsia: a prospective, multicentre, open-label, single-arm clinical trial, investigator-initiated study (HUGS study)

INTRODUCTION

The use of hydroxychloroquine (HCQ) during pregnancies complicated by systemic lupus erythematosus or refractory antiphospholipid antibody syndrome has demonstrated a significant ability to prevent pre-eclampsia (PE). As such, the potential for the administration of HCQ to prevent PE in other high-risk pregnancies is an important clinical research agenda among maternal and fetal medicine specialists. Mechanistically, the anti-inflammatory and immunomodulatory effects of HCQ can offer vascular protection and inhibit the placental dysfunction-associated thrombotic changes underlying the pathophysiology of PE, fetal growth restriction (FGR) and fetal death in utero (FDIU). Placenta-mediated complications exhibit a distinctive overlapping syndrome between pregnancies, and low-dose aspirin is the only prevention method currently in use. This study investigated the effects of improvements in outcomes with HCQ administration in high-risk pregnancies complicated by a previous experience of PE, FGR or FDIU.

METHODS AND ANALYSIS

This multicentre, open-label, single-arm trial commenced on 31 May 2022, in three tertiary hospitals in Korea. Pregnant women with a prior history of PE, FGR or FDIU are eligible to participate. This single-arm study set the previous study with the most similar inclusion criteria, aspirin dose and drug administration period as the comparison group. The required sample size was determined to be 58, with an expected dropout rate of 10%.

ETHICS AND DISSEMINATION

This study protocol was approved by the following institutions and committees: Institutional Review Boards of Chung-Ang University Gwangmyeong Hospital (2304-082-056), Samsung Medical Center (2021-11-087-003) and Kyungpook National University Chilgok Hospital (2021-06-005-006) and the Ministry of Food and Drug Safety. The results will be disseminated to the general public, grant funder, maternal-fetal medicine specialists and other researchers.

TRIAL REGISTRATION NUMBER

NCT05287321.

Chronic Inflammation Offers Hints About Viable Therapeutic Targets for Preeclampsia and Potentially Related Offspring Sequelae

The combination of hypertension with systemic inflammation during pregnancy is a hallmark of preeclampsia, but both processes also convey dynamic information about its antecedents and correlates (e.g., fetal growth restriction) and potentially related offspring sequelae. Causal inferences are further complicated by the increasingly frequent overlap of preeclampsia, fetal growth restriction, and multiple indicators of acute and chronic inflammation, with decreased gestational length and its correlates (e.g., social vulnerability). This complexity prompted our group to summarize information from mechanistic studies, integrated with key clinical evidence, to discuss the possibility that sustained or intermittent systemic inflammation-related phenomena offer hints about viable therapeutic targets, not only for the prevention of preeclampsia, but also the neurobehavioral and other developmental deficits that appear to be overrepresented in surviving offspring. Importantly, we feel that carefully designed hypothesis-driven observational studies are necessary if we are to translate the mechanistic evidence into child health benefits, namely because multiple pregnancy disorders might contribute to heightened risks of neuroinflammation, arrested brain development, or dysconnectivity in survivors who exhibit developmental problems later in life.

Biomarkers in the prediction of complications in pregnancy after assisted reproductive technology

OBJECTIVES

To compare the temporal changes in mean arterial pressure (MAP), uterine artery pulsatility index (UtA-PI), placental growth factor (PlGF), and soluble fms-like tyrosine kinase-1 (sFlt-1) across gestation between assisted reproductive technology (ART) pregnancies complicated with great obstetrical syndromes (GOS) or gestational diabetes (GDM) ± large-for-gestational-age (LGA) fetus, and uncomplicated ART pregnancies.

METHODS

This was a prospective longitudinal study of 143 women with singleton pregnancies who conceived through ART at the Department of Obstetrics and Gynecology, Prince of Wales Hospital, the Chinese University of Hong Kong, Hong Kong SAR between December 2017 and January 2020. The participants were followed up at 6-6+3, 11-13+6, 20-24+6, 30-34+6, and 35-37+6 weeks for the measurement of MAP, UtA-PI, PlGF, and sFlt-1. A linear mixed-effects analysis was performed to compare the biomarkers in the GOS, GDM ± LGA, and uncomplicated groups across gestation.

RESULTS

Thirty-three (23.1%) and fifty-five (31.5%) women were diagnosed with GOS and GDM ± LGA, respectively. The GOS group had higher estimated marginal mean log10 MAP mulitples of the median (MoM) across gestation, compared with the uncomplicated group (0.00771 vs -0.02022; P < 0.001), when adjusting for clinical visits and days of embryo transfer. The absolute mean log10 MAP MoM in the GOS group was found to be significantly higher than that of the uncomplicated group at all clinical visits from 6 weeks onwards. Furthermore, the estimated marginal mean log10 PlGF MoM was significantly lower in the GOS group across gestation, compared with the uncomplicated group (-0.04226 vs 0.05566; P = 0.010). The significant difference in log10 PlGF MoM was observed from 11-13+6 to 30-34+6 week of gestation (P < 0.05). However, no significant differences in the estimated marginal means of log10 UtA-PI MoM and log10 sFlt-1 MoM between GOS and uncomplicated groups were observed. GDM ± LGA group had a lower estimated marginal mean log10 PlGF MoM throughout pregnancy compared with the uncomplicated group (-0.01536 vs 0.05572; P = 0.032). In the individual visit analysis, the significant difference was observed at the 20-24+6 and 35-37+6 weeks visits (P < 0.05). There were no significant differences in estimated marginal mean log10 MoM of MAP, UtA-PI, and sFlt-1 between GDM ± LGA and uncomplicated groups during pregnancy.

CONCLUSION

Our study has revealed that among pregnancies conceived through ART, GOS is associated with higher MAP and lower PlGF from early gestation until late third trimester, while GDM ± LGA is associated with lower PlGF during the second half of pregnancy. The same degree of differences in MAP and PlGF persists from early until late gestation in the GOS group and these findings highlight the importance of early screening during the first trimester to identify women who are at risk for developing GOS following ART procedures. Lastly, the potential of PlGF in predicting the development of GDM from the second trimester of pregnancy requires further investigation.

Investigation of Urotensin II expression in placenta and umbilical cord in pregnancies with intrauterine growth restriction by histological and biochemical methods

OBJECTIVE

In this study, it was aimed to investigate Urotensin II in intrauterine growth restriction (IUGR) and its connection to autophagy and/or apoptosis in placenta and umbilical cord by immunohistochemical and biochemical methods.

MATERIALS AND METHODS

The study included 30 healthy pregnant women and 30 pregnant women with IUGR, aged 19-45, at Atatürk University Gynecology Clinic. Samples were collected from placenta, umbilical cord, maternal blood, and umbilical cord blood during delivery. Histopathological examination was carried out on placenta and umbilical cord, and UTII, Beclin 1, and caspase 3 expressions were analyzed in these tissues. Biochemical analysis was performed on maternal and umbilical cord serum samples.

RESULTS

In healthy placentas, normal villus formation was seen, but those with IUGR showed accelerated villus maturation, causing inadequate nutrition and development. IUGR placentas had fibrin deposition, villous edema, syncytial nodes increase, and intervillous distance. Umbilical cords of IUGR group had differences in vessel wall thickness, arterial lumens, and vessel number. Higher levels of UTII, Beclin 1, and caspase 3 were found in IUGR placenta and cord. Beclin 1 and caspase 3 levels were significantly higher in IUGR group compared to controls, while UTII levels were not significantly different in maternal and cord serums.

CONCLUSION

As a result of our findings, UTII increase in placenta and umbilical cord may lead to IUGR formation by inducing autophagy and apoptosis.

Single-cell RNA sequencing reveals heterogeneity and differential expression of the maternal-fetal interface during ICP and normal pregnancy

OBJECTIVE

Intrahepatic cholestasis of pregnancy (ICP) can cause adverse perinatal outcomes. Previous studies have demonstrated that the placenta of an ICP pregnancy differs in morphology and gene expression from the placenta of a normal pregnancy. To date, however, the genetic mechanism by which ICP affects the placenta is poorly understood. Therefore, the aim of this study was to investigate the differences in main cell types, gene signatures, cell ratio, and functional changes in the placenta between ICP and normal pregnancy.

METHODS

Single-cell RNA sequencing (scRNA-seq) technology was used to detect the gene expression of all cells at the placental maternal-fetal interface. Two individuals were analyzed - one with ICP and one without ICP. The classification of cell types was determined by a graph-based clustering algorithm. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were performed using the R software phyper () function and DAVID website. The differentially expressed genes (DEGs) encoding transcription factors (TFs) were identified using getorf and DIAMOND software.

RESULTS

We identified 14 cell types and 22 distinct cell subtypes that showed unique functional properties. Additionally, we found differences in the proportions of fibroblasts 1, helper T (Th) cells, extravillous trophoblasts, and villous cytotrophoblasts, and we observed heterogeneity of gene expression between ICP and control placentas. Furthermore, we identified 263 DEGs that belonged to TF families, including zf-C2H2, HMGI/HMGY, and Homeobox. In addition, 28 imprinted genes were preferentially expressed in specific cell types, such as PEG3 and PEG10 in trophoblasts as well as DLK1 and DIO3 in fibroblasts.

CONCLUSIONS

Our results revealed the differences in cell-type ratios, gene expression, and functional changes between ICP and normal placentas, and heterogeneity was found among cell subgroups. Hence, the imbalance of various cell types affects placental activity to varying degrees, indicating the complexity of the cell networks that form the placental tissue system, and this alteration of placental function is associated with adverse events in the perinatal period.

Absolute counts of leukocyte subsets in peripheral blood in pregnancies complicated by preterm prelabour rupture of membranes

BACKGROUND

This study aimed to assess variations in the absolute counts of various leukocyte subsets in the peripheral blood of women with pregnancies affected by preterm prelabour rupture of membranes (PPROM), in relation to the presence of intra-amniotic inflammation (IAI).

METHODS

The study included fifty-two women with singleton pregnancies experiencing PPROM. Absolute counts of different leukocyte subpopulations, such as granulocytes, monocytes, lymphocytes, T cells and their subsets, B cells and their subsets, and NK cells and their subsets, were measured in maternal peripheral blood samples using multicolour flow cytometry. IAI was identified by elevated concentrations of interleukin 6 (IL-6) in the amniotic fluid, which was collected through transabdominal amniocentesis.

RESULTS

Women with IAI exhibited higher absolute counts of leukocytes (p = 0.003), granulocytes (p = 0.008), and monocytes (p = 0.009). However, the presence of IAI did not significantly affect the absolute counts of lymphocytes or their subpopulations.

CONCLUSIONS

The study found that IAI is associated with changes in the absolute counts of leukocytes from the innate immunity compartment in the peripheral blood of women with pregnancies complicated by PPROM. Conversely, it does not significantly alter the counts of cells from the adaptive immune system. The changes observed may reflect the natural, temporal, and localised characteristics of IAI.

Development and validation of the placenta-QUS model for the detection of placenta-mediated diseases using quantitative ultrasound measurements: An Ex Vivo proof-of-concept study

INTRODUCTION

Placenta-mediated diseases are associated with structural changes in the placenta. Quantitative Ultrasound (QUS) imaging measures the acoustic properties of the tissue, which are correlated to the underlying tissue structure. We aimed to develop and validate a diagnostic prediction model using QUS measurements for pre-eclampsia (PE) and small-for-gestational-age (SGA) fetuses/neonates.

METHODS

For this prospective case-control study, placentas were collected from a group of women who delivered via cesarean section at BC Women's Hospital, Vancouver, Canada. Ultrasound data were collected and processed to compute three QUS parameters, namely, attenuation coefficient estimate (ACE), integrated backscatter coefficient (IBC), and effective scatterer diameter (ESD) from the placentas. We developed a logistic regression model using QUS parameters as predictors. The primary outcome was the occurrence of SGA and PE.

RESULTS

The dataset consisted of 47 placentas, of which 25 placentas were complicated by SGA/PE. The final placenta-QUS model included quadratic and interaction terms of ACE, IBC, and ESD parameters. The placenta-QUS model was well-calibrated, with a calibration slope of 0.99 (0.57-1.05) and a calibration intercept of 0.003 (-0.02 - 0.22). The model predicted the SGA/PE complicated pregnancies with an apparent Area Under the Receive Operating Characteristic Curve (AUROC) of 0.89 (95 % CI: 0.78-0.98). The optimism-adjusted AUROC was 0.88 (95 % CI: 0.78-0.98).

DISCUSSION

A model for SGA and PE has been developed using QUS measures from the placenta ex vivo. The model showed promising performance in detecting SGA/PE. Future studies will be performed to assess the model performance using QUS measures in utero.

A mitochondrial regulator protein, MNRR1, is elevated in the maternal blood of women with preeclampsia

OBJECTIVE

Preeclampsia, one of the most serious obstetric complications, is a heterogenous disorder resulting from different pathologic processes. However, placental oxidative stress and an anti-angiogenic state play a crucial role. Mitochondria are a major source of cellular reactive oxygen species. Abnormalities in mitochondrial structures, proteins, and functions have been observed in the placentae of patients with preeclampsia, thus mitochondrial dysfunction has been implicated in the mechanism of the disease. Mitochondrial nuclear retrograde regulator 1 (MNRR1) is a newly characterized bi-organellar protein with pleiotropic functions. In the mitochondria, this protein regulates cytochrome c oxidase activity and reactive oxygen species production, whereas in the nucleus, it regulates the transcription of a number of genes including response to tissue hypoxia and inflammatory signals. Since MNRR1 expression changes in response to hypoxia and to an inflammatory signal, MNRR1 could be a part of mitochondrial dysfunction and involved in the pathologic process of preeclampsia. This study aimed to determine whether the plasma MNRR1 concentration of women with preeclampsia differed from that of normal pregnant women.

METHODS

This retrospective case-control study included 97 women with preeclampsia, stratified by gestational age at delivery into early (<34 weeks, n = 40) and late (≥34 weeks, n = 57) preeclampsia and by the presence or absence of placental lesions consistent with maternal vascular malperfusion (MVM), the histologic counterpart of an anti-angiogenic state. Women with an uncomplicated pregnancy at various gestational ages who delivered at term served as controls (n = 80) and were further stratified into early (n = 25) and late (n = 55) controls according to gestational age at venipuncture. Maternal plasma MNRR1 concentrations were determined by an enzyme-linked immunosorbent assay.

RESULTS

1) Women with preeclampsia at the time of diagnosis (either early or late disease) had a significantly higher median (interquartile range, IQR) plasma MNRR1 concentration than the controls [early preeclampsia: 1632 (924-2926) pg/mL vs. 630 (448-4002) pg/mL, p = .026, and late preeclampsia: 1833 (1441-5534) pg/mL vs. 910 (526-6178) pg/mL, p = .021]. Among women with early preeclampsia, those with MVM lesions in the placenta had the highest median (IQR) plasma MNRR1 concentration among the three groups [with MVM: 2066 (1070-3188) pg/mL vs. without MVM: 888 (812-1781) pg/mL, p = .03; and with MVM vs. control: 630 (448-4002) pg/mL, p = .04]. There was no significant difference in the median plasma MNRR1 concentration between women with early preeclampsia without MVM lesions and those with an uncomplicated pregnancy (p = .3). By contrast, women with late preeclampsia, regardless of MVM lesions, had a significantly higher median (IQR) plasma MNRR1 concentration than women in the control group [with MVM: 1609 (1392-3135) pg/mL vs. control: 910 (526-6178), p = .045; and without MVM: 2023 (1578-8936) pg/mL vs. control, p = .01].

CONCLUSIONS

MNRR1, a mitochondrial regulator protein, is elevated in the maternal plasma of women with preeclampsia (both early and late) at the time of diagnosis. These findings may reflect some degree of mitochondrial dysfunction, intravascular inflammation, or other unknown pathologic processes that characterize this obstetrical syndrome.

Determining the effects of paternal obesity on sperm chromatin at histone H3 lysine 4 tri-methylation in relation to the placental transcriptome and cellular composition

Paternal obesity has been implicated in adult-onset metabolic disease in offspring. However, the molecular mechanisms driving these paternal effects and the developmental processes involved remain poorly understood. One underexplored possibility is the role of paternally induced effects on placenta development and function. To address this, we investigated paternal high-fat diet-induced obesity in relation to sperm histone H3 lysine 4 tri-methylation signatures, the placenta transcriptome, and cellular composition. C57BL6/J male mice were fed either a control or high-fat diet for 10 weeks beginning at 6 weeks of age. Males were timed-mated with control-fed C57BL6/J females to generate pregnancies, followed by collection of sperm, and placentas at embryonic day (E)14.5. Chromatin immunoprecipitation targeting histone H3 lysine 4 tri-methylation (H3K4me3) followed by sequencing (ChIP-seq) was performed on sperm to define obesity-associated changes in enrichment. Paternal obesity corresponded with altered sperm H3K4me3 at promoters of genes involved in metabolism and development. Notably, altered sperm H3K4me3 was also localized at placental enhancers. Bulk RNA-sequencing on placentas revealed paternal obesity-associated sex-specific changes in expression of genes involved in hypoxic processes such as angiogenesis, nutrient transport, and imprinted genes, with a subset of de-regulated genes showing changes in H3K4me3 in sperm at corresponding promoters. Paternal obesity was also linked to impaired placenta development; specifically, a deconvolution analysis revealed altered trophoblast cell lineage specification. These findings implicate paternal obesity effects on placenta development and function as one potential developmental route to offspring metabolic disease.

Fatty Acid Metabolism Disruptions: A Subtle yet Critical Factor in Adverse Pregnancy Outcomes

The establishment and maintenance of pregnancy encompass a series of complex and high-energy-consuming physiological processes, resulting in a significant energy demand. Fatty acids, one of the most essential nutrients, play a crucial role in energy supply via oxidation and perform critical biological functions such as anti-inflammatory and anti-oxidant effects, which substantially impact human health. Disordered fatty acid metabolism can cause anomalies in fetal growth and development, as well as a range of pregnancy problems, which can influence the health of both the mother and the fetus. In this review, we innovatively explore the relationship between fatty acid metabolism abnormalities and pregnancy complications, emphasizing the potential of dietary interventions with polyunsaturated fatty acids in improving pregnancy outcomes. These findings provide important evidence for clinical interventions and enhance the understanding and practical application of health management during pregnancy.

Cross-Species Insights into Trophoblast Invasion During Placentation Governed by Immune-Featured Trophoblast Cells

Proper development of the placenta, the transient support organ forms after embryo implantation, is essential for a successful pregnancy. However, the regulation of trophoblast invasion, which is most important during placentation, remains largely unknown. Here, rats, mice, and pigs are used as biomedical models, used scRNA-seq to comparatively elucidate the regulatory mechanism of placental trophoblast invasion, and verified it using a human preeclampsia disease model combined with scStereo-seq. A dual-featured type of immune-featured trophoblast (iTrophoblast) is unexpectedly discovered. Interestingly, iTrophoblast only exists in invasive placentas and regulates trophoblast invasion during placentation. In a normally developing placenta, iTrophoblast gradually transforms from an immature state into a functional mature state as it develops. Whereas in the developmentally abnormal preeclamptic placenta, disordered iTrophoblast transformation leads to the accumulation of immature iTrophoblasts, thereby disrupting trophoblast invasion and ultimately leading to the progression of preeclampsia.

Placental differences between severe fetal growth restriction and hypertensive disorders of pregnancy requiring early preterm delivery: morphometric analysis of the villous tree supported by artificial intelligence

BACKGROUND

The great obstetrical syndromes of fetal growth restriction and hypertensive disorders of pregnancy can occur individually or be interrelated. Placental pathologic findings often overlap between these conditions, regardless of whether 1 or both diagnoses are present. Quantification of placental villous structures in each of these settings may identify distinct differences in developmental pathways.

OBJECTIVE

This study aimed to determine how the quantity and surface area of placental villi and vessels differ between severe, early-onset fetal growth restriction with absent or reversed umbilical artery Doppler indices and hypertensive disorders of pregnancy or the 2 conditions combined among subjects with disease severity that warrant early preterm delivery. We hypothesized that the trajectories of placental morphogenesis diverge after a common initiating insult of deep defective placentation. Specifically, we postulated that only villi are affected in pregnancy-related hypertension, whereas both villous and vascular structures are proportionally diminished in severe fetal growth restriction with no additional effect when hypertension is concomitantly present.

STUDY DESIGN

In this retrospective cohort study, paraffin-embedded placental tissue was obtained from 4 groups, namely (1) patients with severe fetal growth restriction with absent or reversed umbilical artery end-diastolic velocities and hypertensive disorders of pregnancy, (2) patients with severe fetal growth restriction with absent or reversed umbilical artery Doppler indices and no hypertension, (3) gestational age-matched, appropriately grown pregnancies with hypertensive disease, and (4) gestational age-matched, appropriately grown pregnancies without hypertension. Dual immunohistochemistry for cytokeratin-7 (trophoblast) and CD34 (endothelial cells) was performed, followed by artificial intelligence-driven morphometric analyses. The number of villi, total villous area, number of fetoplacental vessels, and total vascular area across villi within a uniform region of interest were quantified. Quantitative analyses of placental structures were modeled using linear regression.

RESULTS

Placentas from pregnancies complicated by hypertensive disorders of pregnancy exhibited significantly fewer stem villi (-282 stem villi; 95% confidence interval, -467 to -98; P<.01), a smaller stem villous area (-4.3 mm2; 95% confidence interval, -7.3 to -1.2; P<.01), and fewer stem villous vessels (-4967 stem villous vessels; 95% confidence interval, -8501 to -1433; P<.01) with no difference in the total vascular area. In contrast, placental abnormalities in cases with severe growth restriction were limited to terminal villi with global decreases in the number of villi (-873 terminal villi; 95% confidence interval, -1501 to -246; P<.01), the villous area (-1.5 mm2; 95% confidence interval, -2.7 to -0.4; P<.01), the number of blood vessels (-5165 terminal villous vessels; 95% confidence interval, -8201 to -2128; P<.01), and the vascular area (-0.6 mm2; 95% confidence interval, -1.1 to -0.1; P=.02). The combination of hypertension and growth restriction had no additional effect beyond the individual impact of each state.

CONCLUSION

Pregnancies complicated by hypertensive disorders of pregnancy exhibited defects in the stem villi only, whereas placental abnormalities in severely growth restricted pregnancies with absent or reversed umbilical artery end-diastolic velocities were limited to the terminal villi. There were no significant statistical interactions in the combination of growth restriction and hypertension, suggesting that distinct pathophysiological pathways downstream of the initial insult of defective placentation are involved in each entity and do not synergize to lead to more severe pathologic consequences. Delineating mechanisms that underly the divergence in placental development after a common inciting event of defective deep placentation may shed light on new targets for prevention or treatment.