Placental hypoxia: the lesions of maternal malperfusion

Immunogenicity-related placental infarcts and abortions in nonhuman primate developmental and reproductive toxicity studies: Proposed mechanism and impact on study interpretation

Previous analysis of 3 developmental toxicity studies (1 EFD, 2 ePPND) conducted in cynomolgus monkeys for biotherapeutics indicated an association between immunogenicity and abortions. This led to the hypothesis that immunogenic responses to biotherapeutics administered to pregnant nonhuman primates (NHPs) can cause altered placental hemodynamics and/or vascular pathology, resulting in placental infarcts and abortion secondary to compromised uteroplacental perfusion. Retrospective analysis of an additional 17 NHP developmental and reproductive toxicity (DART) studies was conducted for further support of this hypothesis. Of 366 placentas evaluated from the 20 total studies (2 EFD, 18 ePPND), 18 % (n = 66) had central placental infarctions/hematomas associated with maternal immunogenicity; these were significant enough to lead to abortion in 32/66 (48 %) of these pregnancies. Abortions in anti-drug antibody positive females with placental infarction were found in 40 % (n = 8) of the studies but accounted for only a 5 % fetal loss rate. Thus, although immunogenicity was commonly observed in these studies, its impact to study outcome/interpretation was manageable in most cases. In the event of immune-mediated responses such as formation of anti-drug antibodies and/or abnormal placental morphology (e.g., infarcts), it is imperative to take a carefully considered, weight-of-evidence approach to interpretation of direct (test article related) vs. indirect (secondary to immunogenicity) effects. In cases where the biotherapeutic being tested is expected to be highly immunogenic in an NHP DART study, with potential confounding impact to study interpretation, alternatives to NHPs should be given high priority in the strategic approach to developmental toxicity testing.

A machine learning model based on placental magnetic resonance imaging and clinical factors to predict fetal growth restriction

OBJECTIVES

To create a placental radiomics-clinical machine learning model to predict FGR.

MATERIALS AND METHODS

Retrospectively analyzed placental MRI and clinical data of 110 FGR cases and 158 healthy controls at 28-37 weeks of gestation from two campuses of ZWH. 227 cases from Hubin campus were randomly divided into training (n = 182) and internal testing set (n = 45). 41 cases from Xiaoshan campus were included in external testing set. Placental MRI features were extracted from sagittal T2WI. Mann-Whitney U test, redundancy analysis, and LASSO were used to identify the radiomics signature, and the best-performing radiomics model was constructed by comparing eight machine learning algorithms. Clinical factors determined by univariate and multivariate analyses. A united model and nomogram combining the radiomics Rad-score and clinical factors were established. The performance of the models was assessed by DeLong test, calibration curve and decision curve analysis.

RESULTS

Of 1561 radiomics features, 10 strongly correlated with FGR were selected. The radiomics model using logistic regression performed best compared eight algorithms. 5 important clinical features identified by analysis. The united model demonstrated a good predictive performance in the training, internal testing and external testing sets, with AUC 0.941 (95% CI, 0.0.904-0.977), 0.899 (95% CI, 0.789-1) and 0.861 (95% CI 0.725-0.998), prediction accuracies 0.885, 0.844 and 0.805, precisions 0.871, 0.789 and 0.867, recalls 0.836, 0.833 and 0.684, and F1 scores 0.853, 0.811 and 0.765, respectively. The calibration and decision curves of the united model also showed good performance. Nomogram confirmed clinical applicability of the model.

CONCLUSIONS

The proposed placental radiomics-clinical machine learning model is simple yet effective to predict FGR.

Placental histopathology in early-onset fetal growth restriction with use of sildenafil, a secondary analysis of the Dutch STRIDER study

OBJECTIVES

Placental pathology lesions are common in early-onset fetal growth restriction (eoFGR). Therapeutic interventions to improve eoFGR outcomes are needed. In the international STRIDER trials (Sildenafil Therapy In Dismal prognosis Early-onset intrauterine growth Restriction) sildenafil didn't improve perinatal outcomes of eoFGR. We aimed to study the underlying placental pathology in the Dutch STRIDER trial and the effects of sildenafil on placental histopathology by describing the associations with sildenafil treatment, placental-dysfunction serum biomarkers and markers of oxidative stress.

METHODS

The Dutch STRIDER trial was a randomized controlled trial of sildenafil versus placebo in 216 singleton pregnancies complicated by eoFGR, included between 20+0- and 29+6-weeks' gestation. In 158 cases, placental histology was available. Lesions were classified independently by three perinatal pathologists blinded for clinical data, according to the international criteria of the Amsterdam Placental Workshop Group Consensus Statement. Blood samples taken at inclusion were analyzed for free thiols (FT), placental growth factor (PlGF) and soluble FMS-like tyrosine kinase-1 (sFlt-1, n = 85).

RESULTS

The 'big four' placental lesions (maternal and fetal vascular malperfusion, and chronic or acute inflammatory lesions) were equally distributed in both groups. However, massive perivillous fibrin deposition (MPFD) and chronic histiocytic intervillositis (CHIV) were less common in the sildenafil-treated group compared to the placebo-treated group (p = 0.026 and p = 0.043). FT, PlGF and sFlt-1 at inclusion were not discriminative for placental lesions.

CONCLUSIONS

Sildenafil had no effect on common placental lesions. The lower incidence of MPFD and CHIV after sildenafil exposure merits more research on the interaction between sildenafil and the immune system.

Cross-modal contrastive learning for unified placenta analysis using photographs

The placenta is vital to maternal and child health but often overlooked in pregnancy studies. Addressing the need for a more accessible and cost-effective method of placental assessment, our study introduces a computational tool designed for the analysis of placental photographs. Leveraging images and pathology reports collected from sites in the United States and Uganda over a 12-year period, we developed a cross-modal contrastive learning algorithm consisting of pre-alignment, distillation, and retrieval modules. Moreover, the proposed robustness evaluation protocol enables statistical assessment of performance improvements, provides deeper insight into the impact of different features on predictions, and offers practical guidance for its application in a variety of settings. Through extensive experimentation, our tool demonstrates an average area under the receiver operating characteristic curve score of over 82% in both internal and external validations, which underscores the potential of our tool to enhance clinical care across diverse environments.

Association of neonatal outcome with birth weight for gestational age in Chinese very preterm infants: a retrospective cohort study

BACKGROUND

The neonatal outcomes across different percentiles of birth weight for gestational age are still unclear.

METHODS

This retrospective cohort study was conducted within 57 tertiary hospitals participating in the Chinese Neonatal Network (CHNN) from 25 provinces throughout China. Infants with gestational age (GA) 24+0-31+6 weeks who were admitted within 7 days after birth were included. The composite outcome was defined as mortality or any one of neonatal major morbidities, including necrotizing enterocolitis (NEC), bronchopulmonary dysplasia (BPD), severe intraventricular hemorrhage (IVH), cystic periventricular leukomalacia (cPVL), severe retinopathy of prematurity (ROP), and sepsis. Multivariable logistic regressions using generalized estimating equation approach were conducted.

RESULTS

A total of 8380 infants were included with a mean GA of 30 (28-31) weeks. Of these, 1373 (16.5%) were born at less than 28 weeks, while 6997 (83.5%) had a GA between 28 and 32 weeks. Our analysis indicated that the risk of composite outcomes was negatively associated with birth weight for gestational age, and compared to the reference group, the multiple-adjusted ORs (95%CI) of composite outcomes were 4.89 (3.51-6.81) and 2.16 (1.77-2.63) for infants with birth weight for gestational less than 10th percentile and 10th -30th percentile, respectively. The ORs (95%CI) of mortality, NEC, BPD, severe ROP, and sepsis in infants with birth weight for gestational age at 10th-30th percentile were 1.94 (1.56-2.41), 1.08 (0.79-1.47), 2.48 (2.03-3.04), 2.35 (1.63-3.39), and 1.39 (1.10-1.77), respectively.

CONCLUSION

Our study suggested that the risk of adverse neonatal outcomes increased significantly when the birth weight for gestational age was below the 30th percentile. Regular monitoring and early intervention are crucial for these high-risk infants.

Placental Histopathological Lesions and Adverse Neonatal Outcomes in Patients with Inflammatory Bowel Diseases- A retrospective Cohort Study

Inflammatory bowel diseases (IBD) are significantly associated with adverse pregnancy and neonatal outcomes, though the pathomechanism is yet unknown. To investigate the relationship between IBD and adverse pregnancy outcomes by comparing neonatal outcomes and placental histopathology in two matched groups of patients with and without IBD. In this retrospective study, data of all patients who gave birth between 2008-2021 and were diagnosed with IBD were reviewed and compared to a control group matching two control cases for every IBD case. Neonatal outcomes and placental pathology were compared between the groups. Compared to the control group (n=76), the placentas of patients with IBD (n=36) were characterized by significantly lower placental weight (p < 0.001), and higher rates of maternal vascular malperfusion lesions (MVM, p < 0.001) and maternal and fetal inflammatory response lesions (p < 0.001). Neonates of patients with IBD were more frequently small for gestational age (SGA) (p=0.01), with increased rates of need for phototherapy (p = 0.03), respiratory morbidity and NICU admission (p < 0.001 for both outcomes). Multivariate logistic regression analyses adjusting for possible confounders (including maternal age, gestational age, chronic hypertension, smoking, and thrombophilia) confirmed the independent association between IBD and composite MVM lesions (aOR 4.31, p < 0.001), maternal inflammatory responses (aOR 40.22, p < 0.001) and SGA infants (aOR 4.31, p = 0.013). IBD is associated with increased rates of placental histopathological lesions and adverse pregnancy outcomes, including SGA infants. These novel findings imply the role of placental malperfusion and inflammatory processes in pregnancy complications of IBD patients, which should be followed accordingly. Approval of local ethics committee # WOMC-0219-20.

Collateral Damage in the Placenta during Viral Infection in Pregnancy: A Possible Mechanism for Vertical Transmission and an Adverse Pregnancy Outcome

In mammals, the placenta is a connection between a mother and a new developing organism. This tissue has a protective function against some microorganisms, transports nutrients, and exchanges gases and excretory substances between the mother and the fetus. Placental tissue is mainly composed of chorionic villi functional units called trophoblasts (cytotrophoblasts, the syncytiotrophoblast, and extravillous trophoblasts). However, some viruses have developed mechanisms that help them invade the placenta, causing various conditions such as necrosis, poor perfusion, and membrane rupture which, in turn, can impact the development of the fetus and put the mother's health at risk. In this study, we collected the most relevant information about viral infection during pregnancy which can affect both the mother and the fetus, leading to an increase in the probability of vertical transmission. Knowing these mechanisms could be relevant for new research in the maternal-fetal context and may provide options for new therapeutic targets and biomarkers in fetal prognosis.

Associations between placental pathology and poor intrauterine growth among a cohort of mother-infant singleton pairs in Leyte, the Philippines

OBJECTIVE

Poor intrauterine growth has negative impacts for child growth and development and disproportionately affects children living in low-resource settings. In the present study, we investigated relationships between placental pathologies and indicators of poor intrauterine growth.

METHODS

We enrolled a longitudinal cohort of 279 mother-infant pairs from Leyte, the Philippines. Placental measures included characteristics, pathological findings, and immunohistochemistry. At birth, intrauterine growth was assessed using anthropometric measures, weight-for-gestational age, and the clinical assessment of nutritional status score (CANSCORE) for determining fetal malnutrition. Multivariate linear regression and log-binomial regression models were applied, controlling for potential confounding factors.

RESULTS

Maternal vascular malperfusion (MVM) was related to reduced birthweight (P < 0.0001), birth length (P = 0.002), head circumference (P = 0.001), and weight-to-length ratio (P = 0.016). MVM increased the risk for preterm delivery (P = 0.0005) and small for gestational age (SGA) (P = 0.016). Acute chorioamnionitis (P = 0.013) and MVM (P = 0.021) both led to an increased risk for fetal malnutrition defined by CANSORE<25. Villous tissue activated caspase-3 was associated with lower birth length (P = 0.0006), higher weight-to-length ratio (P = 0.004), reduced risks for SGA (P = 0.011) and low weight-to-length ratio for gestational age (P = 0.004).

CONCLUSION

The present study applied comprehensive measures for intrauterine growth and demonstrates that low placental weight and placental pathology, chiefly MVM, contribute to poor intrauterine growth. A better understanding of the mechanistic role of specific placental pathologies on adverse newborn outcomes will provide opportunities for reducing incidence of poor intrauterine growth and associated long-term morbidities.

Placental syndromes and long-term risk of hypertension

Higher blood pressure prior to pregnancy is associated with increased risk of placental abruption, hypertension and preeclampsia, preterm delivery and fetal growth restriction. These conditions are jointly termed placental syndromes as they are characterised by impaired placentation and early placental vascularization. Placental syndromes are associated with an increased maternal risk of progression to hypertension and cardiovascular disease (CVD) in later life. Women affected by both a clinical placental syndrome and with evidence of placental maternal vascular malperfusion (MVM) have a particularly high risk of hypertension and CVD. Yet whether placental impairment and clinical syndromes are causes or consequences of higher blood pressure in women remains unclear. In this review, we address the relationship between blood pressure and maternal health in pregnancy. We conclude that there is a pressing need for studies with a range of detailed measures of cardiac and vascular structure and function taken before, during and after pregnancy to solve the 'chicken and egg' puzzle of women's blood pressure and pregnancy health, and to inform effective precision medicine prevention and treatment of both placental syndromes and chronic hypertension in women.

Anatomy of the Ductus Arteriosus in Fetal Autopsies: Correlations With Placental Pathology and Cause of Death

BACKGROUND

Differences in the shape of the ductus arteriosus (DA), an important vascular shunt between the pulmonary artery and aorta, may reflect fetoplacental blood flow. Our aim was to examine tapering of the DA in a fetal autopsy population and correlate it with placental pathology and cause of death (COD).

METHODS

This autopsy case control study of stillborn fetuses selected cases (tapered DA) and consecutive age-matched controls (no DA tapering) between January 2017 and January 2022. We abstracted demographic and clinical data from pathology reports. Autopsy data included COD and histologic evidence of fetal hypoxia. Placental pathology included umbilical cord abnormalities, acute and chronic inflammation, fetal vascular malperfusion (FVM), and maternal vascular malperfusion (MVM).

RESULTS

We identified 50 cases and 50 controls. Gestational age ranged from 18 to 38 weeks. Maternal and fetal demographic characteristics did not differ significantly between cases and controls. COD related to an umbilical cord accident/FVM was significantly more prevalent in cases vs controls (46% vs 26%, P = .037), and FVM in the placenta, regardless of COD, trended higher in cases than controls.

CONCLUSION

Tapering of the DA is present in stillborn fetuses and associated with COD related to fetal vascular blood flow obstruction.

Molecular Pathways of Altered Brain Development in Fetuses Exposed to Hypoxia

Perinatal hypoxia is a major cause of neurodevelopmental impairment and subsequent motor and cognitive dysfunctions; it is associated with fetal growth restriction and uteroplacental dysfunction during pregnancy. This review aims to present the current knowledge on brain development resulting from perinatal asphyxia, including the causes, symptoms, and means of predicting the degree of brain damage. Furthermore, this review discusses the specificity of brain development in the growth-restricted fetus and how it is replicated and studied in animal models. Finally, this review aims at identifying the least understood and missing molecular pathways of abnormal brain development, especially with respect to potential treatment intervention.

Investigation of CD56, ADAM17 and FGF21 Expressions in the Placentas of Preeclampsia Cases

Objective: In the present study, we investigated the expression of CD56, ADAM17 and FGF21 antibodies (Ab), which we think have an effect on the pathophysiology of preeclampsia (PE), in pregnant patients with healthy placentas and placentas with PE. The expression of these antibodies has been investigated in a limited amount of former research, but their role in PE has not yet been clarified. With this study, we aimed to contribute to the elucidation of the pathophysiology of PE and the detection of new target molecules for treatment. Materials and Methods: Parturients with singleton pregnancy at 32 weeks or above without any maternal or fetal pathology who were admitted to the Department of Obstetrics and Gynecology, Zonguldak Bülent Ecevit University Practice and Research Hospital between 11 January 2020 and 7 January 2022 were included in the present study. Pregnant women with coexisting disease or a pathology related to the placenta (ablation placenta, vasa previa, hemangioma, etc.) were excluded. CD56, ADAM17 and FGF21 antibodies were histopathologically and immunohistochemically detected in 60 placentas with PE (study group) and 43 healthy placentas (control group). Results: CD56, ADAM17 and FGF21 proteins were all more intensely expressed in preeclamptic placentas and a statistically significant difference was found between the two groups for all three antibodies (p < 0.001). Deciduitis, perivillous fibrin deposition, intervillous fibrin, intervillous hemorrhage, infarct, calcification, laminar necrosis and syncytial node were found to be significantly more common in the study group (p < 0.001). Conclusions: We observed that CD56, ADAM17 and FGF21 expressions increased in preeclamptic placentas. These Ab may be responsible for the pathogenesis of PE, which can be illuminated with further studies.

Placental pathology findings in perinatal deaths from 28 weeks gestation in Aotearoa New Zealand

INTRODUCTION

Women of South Asian ethnicity are overrepresented in adverse pregnancy outcome across high-income countries, including those related to placental dysfunction. It has been hypothesised that placental aging occurs at earlier gestation in South Asian pregnancies. We aimed to identify differences in placental pathology among perinatal deaths ≥28 weeks gestation, between South Asian, Māori and New Zealand (NZ) European women in Aotearoa NZ, with a focus on women of South Asian ethnicity.

METHODS

Placental pathology reports and clinical data from perinatal deaths between 2008 and 2017 were provided by the NZ Perinatal and Maternal Mortality Review Committee, blinded, and analysed by an experienced perinatal pathologist using the Amsterdam Placental Workshop Group Consensus Statement criteria.

RESULTS

790 of 1161 placental pathology reports, 346 preterm (28⁺⁰ to 36⁺⁶ weeks) and 444 term (≥37⁺⁰ weeks) deaths, met the inclusion criteria. Among preterm deaths, South Asian women had higher rates of maternal vascular malperfusion compared with Māori (aOR 4.16, 95%CI 1.55-11.15) and NZ European (aOR 2.60, 95%CI 1.10-6.16). Among term deaths, South Asian women had higher rates of abnormal villous morphology compared with Māori (aOR 2.19, 95%CI 1.04-4.62) and NZ European (aOR 2.12, 95%CI 1.14-3.94), mostly due to increased rates of chorangiosis (36.7%, compared to 23.3% and 21.7%, respectively).

DISCUSSION

Differences in placental pathology by ethnicity were observed among preterm and term perinatal deaths. While we suspect differing underlying causal pathways, these deaths may be associated with maternal diabetic and red blood cell disorders among South Asian women, leading to a hypoxic state in-utero.

Association of placental histology and neonatal hematologic outcomes

OBJECTIVE

The objective of the paper was to investigate how neonatal hematologic outcomes vary by major placental histopathology categories.

STUDY DESIGN

Placental pathology reports from 5263 subjects were coded into individual placental lesions. Infant hematologic data (complete blood count parameters (n = 1945), transfusions, and phototherapy) were compared by placental pathologic phenotype.

RESULTS

Red blood cell transfusions were more likely with maternal vascular malperfusion (MVM; OR 9.4 [2.2, 40.8]) and chronic inflammation (1.7 [1.04, 2.7]). White blood cells were decreased with MVM (10.6 103/μL vs 16.4) and elevated with acute inflammation (AI; 18.6 vs 11.9). Thrombocytopenia was associated with MVM (OR 3.7 [2.2, 5.1]) and fetal vascular malperfusion (FVM; OR 2.6 [1.5, 4.6]). Platelet transfusions were more likely with MVM (OR 8.3 [4.6, 15.0]) and FVM (OR 2.9 [1.4, 6.1]). Phototherapy was associated with MVM (OR 3.3 [2.7, 4.0]) and AI (OR 0.8 [0.6, 0.9]).

CONCLUSIONS

Neonatal hematologic outcomes are associated with the in utero environment described by placental pathology.

Vascular Malperfusion – As a Morphological Pattern of Preeclampsia

Introduction. The system « mother-placenta-fetus » is in a complex functional balance, and dysfunction of any of the components can compromise others. The placenta plays an important role in the development of preeclampsia, since preeclampsia can occur in the absence of a fetus, but in the presence of a trophoblast. In this regard, the study of morphological placental patterns in preeclampsia can give an idea of preeclampsia as a pathology in general, as well as its relationship with hypoxic damage to the fetus. Aim.  Identification of morphological patterns of placental lesions associated with preeclampsia. Materials and methods. A retrospective morphological study of 355 placentas sent for histological examination in the period from 2015 to 2020 was carried out. During the analyzed period, 184 placentas from pregnancies with an established diagnosis of preeclampsia and 171 placentas from pregnancies with a physiological course were studied. Results. It has been established that preeclampsia is associated with a smaller mass, size and height of the placenta. As morphological patterns associated with preeclampsia, such histological signs of maternal vascular malperfusion, such as infarcts, arterial atherosclerosis, etc., were identified. Conclusions. The heterogeneity of clinical and histological signs associated with both the physiological and pathological course of pregnancy reflects the different gestational age of the onset of the disease and the stage of development of the adaptive capabilities of the placenta. Identification of morphological patterns associated with hypoxic damage to the fetus allows us to identify a group of newborns with a high risk of chronic hypoxic damage in the perinatal period and to stratify the risk group in the postnatal period in order to reduce infant morbidity and mortality.

Roles of maternal HDL during pregnancy

BACKGROUND

High density lipoproteins (HDL) were first linked to cardiovascular disease (CVD) over 30 years ago when an inverse relationship was shown between CVD and HDL-cholesterol levels. It is now apparent that HDL composition and function, not cholesterol levels, are the pertinent measurements describing HDL's role in various disease processes, especially those with subclinical or overt inflammation.

SCOPE OF REVIEW

Pregnancy is also an inflammatory state. When inflammation becomes excessive during pregnancy, there is an increased risk for adverse outcomes that affect the health of the mother and fetus, including preterm birth and preeclampsia. Though studies on HDL during pregnancy are limited, recent evidence demonstrates that HDL composition and function change during pregnancy and in women with adverse outcomes.

GENERAL SIGNIFICANCE

In this review, we will discuss how HDL may play a role in maintaining a healthy pregnancy and how impairments in function could lead to pregnancies with adverse outcomes.

Syncytiotrophoblast stress in preeclampsia: the convergence point for multiple pathways

Preeclampsia evolves in 2 stages: a placental problem that generates signals to the mother to cause a range of responses that comprise the second stage (preeclampsia syndrome). The first stage of early-onset preeclampsia is poor placentation, which we here call malplacentation. The spiral arteries are incompletely remodeled, leading to later placental malperfusion, relatively early in the second half of pregnancy. The long duration of the first stage (several months) is unsurprisingly associated with fetal growth restriction. The first stage of late-onset preeclampsia, approximately 80% of total cases, is shorter (several weeks) and part of a process that is common to all pregnancies. Placental function declines as it outgrows uterine capacity, with increasing chorionic villous packing, compression of the intervillous space, and fetal hypoxia, and causes late-onset clinical presentations such as "unexplained" stillbirths, late-onset fetal growth restriction, or preeclampsia. The second stages of early- and late-onset preeclampsia share syncytiotrophoblast stress as the most relevant feature that causes the maternal syndrome. Syncytiotrophoblast stress signals in the maternal circulation are probably the most specific biomarkers for preeclampsia. In addition, soluble fms-like tyrosine kinase-1 (mainly produced by syncytiotrophoblast) is the best-known biomarker and is routinely used in clinical practice in many locations. How the stress signals change over time in normal pregnancies indicates that syncytiotrophoblast stress begins on average at 30 to 32 weeks' gestation and progresses to term. At term, syncytiotrophoblast shows increasing markers of stress, including apoptosis, pyroptosis, autophagy, syncytial knots, and necrosis. We label this phenotype the "twilight placenta" and argue that it accounts for the clinical problems of postmature pregnancies. Senescence as a stress response differs in multinuclear syncytiotrophoblast from that of mononuclear cells. Syncytiotrophoblast irreversibly acquires part of the senescence phenotype (cell cycle arrest) when it is formed by cell fusion. The 2 pathways converge on the common pathologic endpoint, syncytiotrophoblast stress, and contribute to preeclampsia subtypes. We highlight that the well-known heterogeneity of the preeclampsia syndrome arises from different pathways to this common endpoint, influenced by maternal genetics, epigenetics, lifestyle, and environmental factors with different fetal and maternal responses to the ensuing insults. This complexity mandates a reassessment of our approach to predicting and preventing preeclampsia, and we summarize research priorities to maximize what we can learn about these important issues.

Maternal Vascular Lesions in the Placenta Predict Vascular Impairments a Decade After Delivery

Women with adverse pregnancy outcomes later experience excess hypertension and cardiovascular disease, but how the events are linked is unknown. Examination of the placenta may provide clues to vascular impairments after delivery. Maternal vascular malperfusion lesions (MVMs) were abstracted from clinical reports, validated and characterized using clinical guidelines and severity score. A total of 492 women (170 with MVMs and 322 without MVMs) participated in a study visit 8 to 10 years after delivery to assess blood pressure, cardiometabolic factors, and sublingual microvascular features using sidestream dark field imaging. Covariates included age, race, adverse pregnancy outcomes (preeclampsia, small for gestational age, and preterm birth), and health behaviors. Women with versus without MVM had a distinct sublingual microvascular profile comprised of (1) lower microvascular density (-410 μm/mm², P=0.015), (2) higher red blood cell filling as a marker of perfusion (2%, P=0.004), and (3) smaller perfused boundary region (-0.07 µm, P=0.025) as a measure of glycocalyx integrity, adjusted for covariates including adverse pregnancy outcomes. Women with MVM also had higher adjusted diastolic blood pressure (+2.6 mm Hg, P=0.021), total and LDL (low-density lipoprotein)-cholesterol (+11.2 mg/dL, P=0.016; +8.7 mg/dL, P=0.031). MVM associations with subsequent cardiovascular measures did not vary by type of adverse pregnancy outcome, except among women with preterm births where blood pressure was higher only among those with MVM. Results were similar when evaluated as MVM severity. A decade after delivery, women with placental vascular lesions had an adverse cardiovascular profile comprised of microvascular rarefaction, higher blood pressure and more atherogenic lipids. Placental histopathology may reveal a woman's early trajectory toward subsequent vascular disease.

Postpartum preeclampsia or eclampsia: defining its place and management among the hypertensive disorders of pregnancy

High blood pressure in the postpartum period is most commonly seen in women with antenatal hypertensive disorders, but it can develop de novo in the postpartum time frame. Whether postpartum preeclampsia or eclampsia represents a separate entity from preeclampsia or eclampsia with antepartum onset is unclear. Although definitions vary, the diagnosis of postpartum preeclampsia should be considered in women with new-onset hypertension 48 hours to 6 weeks after delivery. New-onset postpartum preeclampsia is an understudied disease entity with few evidence-based guidelines to guide diagnosis and management. We propose that new-onset hypertension with the presence of any severe features (including severely elevated blood pressure in women with no history of hypertension) be referred to as postpartum preeclampsia after exclusion of other etiologies to facilitate recognition and timely management. Older maternal age, black race, maternal obesity, and cesarean delivery are all associated with a higher risk of postpartum preeclampsia. Most women with delayed-onset postpartum preeclampsia present within the first 7 to 10 days after delivery, most frequently with neurologic symptoms, typically headache. The cornerstones of treatment include the use of antihypertensive agents, magnesium, and diuresis. Postpartum preeclampsia may be associated with a higher risk of maternal morbidity than preeclampsia with antepartum onset, yet it remains an understudied disease process. Future research should focus on the pathophysiology and specific risk factors. A better understanding is imperative for patient care and counseling and anticipatory guidance before hospital discharge and is important for the reduction of maternal morbidity and mortality in the postpartum period.

Clinicopathologic Study of Placentas From Women With a Fontan Circulation

BACKGROUND

Pregnant women with a Fontan circulation have a high risk of obstetric complications, such as preterm delivery and small for gestational age (SGA), which may be affected by low blood flow to the placenta and hypoxia. This study investigated placental pathology in a Fontan circulation.

METHODS AND RESULTS

Eighteen pregnancies in 11 women with a Fontan circulation were reviewed. Pregnancy outcomes showed 9 miscarriages and 9 live births, with 4 preterm deliveries. Five neonates were SGA (<5th percentile). Eight placentas from live births in 7 women were available for the study. Five placentas had low weight placenta for gestational age, and 7 grossly showed a chronic subchorionic hematoma. Histological examination revealed all placentas had some form of histological hypoxic lesions: maternal vascular malperfusion in 7, fetal vascular malperfusion in 1, and other hypoxia-related lesions in 8. Quantitative analyses, including immunohistochemistry (CD31, CD68, and hypoxia inducible factor-1α antibodies) and Masson's trichrome staining, were also performed and compared with 5 control placentas. Capillary density and the area of fibrosis were significantly greater in placentas from women with a Fontan circulation than in control placentas.

CONCLUSIONS

Placentas in a Fontan circulation were characterized by a high frequency of low placental weight, chronic subchorionic hematoma, and constant histological hypoxic changes, which could reflect altered maternal cardiac conditions and lead to poor pregnancy outcomes.

Meconium-stained amniotic fluid and histologic signs of fetal distress in stillbirths

OBJECTIVE

Stillbirth is one of the most devastating adverse pregnancy outcome, but it is often associated with a missing post-mortem histological examination. We aimed at evaluating whether the staining of amniotic fluid reflects the fetal conditions surrounding the death and if it correlates with any histologic sign of fetal distress.

STUDY DESIGN

Terminal gasping (represented by the massive presence of intra-alveolar squamous cells), thymic and adrenal cortex modifications were evaluated as histologic signs of fetal distress in stillbirths, and stratified according to the degree of staining of the amniotic fluid.

RESULTS

The presence of meconium-stained amniotic fluid did not correlate with the presence of gasping and/or thymic and/or adrenal cortex changes. Clear amniotic fluid was not associated with the absence of histologic signs of distress.

CONCLUSIONS

The evaluation of the staining of the amniotic fluid fails to identify distressed fetuses. A histologic evaluation of fetal organs provides detailed information, irrespective of the presence/absence of meconium-stained amniotic fluid.

Association of second trimester uterine artery Doppler parameters with maternal hypertension 2–7 years after delivery

Background

Reduced uterine artery compliance is associated with adverse pregnancy outcomes (APOs) and may indicate underlying maternal cardiovascular pathology. We investigated associations between second trimester uterine artery Doppler (UAD) parameters and incident maternal hypertension 2–7 years after delivery.

Methods

A cohort of 10,038 nulliparous US participants was recruited early in pregnancy. A subgroup of 3739, without baseline hypertension and with complete follow-up visits 2–7 years after delivery, were included in this analysis. We investigated UAD indicators of compliance including: 1) early diastolic notch; 2) resistance index (RI); and 3) pulsatility index (PI). We defined hypertension as systolic blood pressure ≥130 mmHg, diastolic ≥80 mmHg, or antihypertensive medication use. We calculated odds ratios (OR) and 95 % confidence intervals (95%CI) for associations between UAD parameters and hypertension, adjusting for age, obesity, race/ethnicity, insurance, smoking, and APOs.

Results

A total of 187 (5 %) participants developed hypertension after the index pregnancy. Presence of early diastolic notch on UAD was not associated with incident hypertension. Increased RI and PI correlated with higher odds of hypertension (RI: adjusted OR 1.15 [95 % CI 1.03–1.30]; PI: adjusted OR 1.03 [95%CI 1.01–1.05] for each 0.1 unit increase). Maximum RI above 0.84 or maximum PI above 2.3 more than doubled the odds of incident hypertension (RI: adjusted OR 2.49, 95%CI 1.45–4.26; PI: adjusted OR 2.36, 95%CI 1.45–3.86).

Conclusion

Higher resistance and pulsatility indices measured on second trimester UAD were associated with increased odds of incident hypertension 2–7 years later, and may be biomarkers of higher maternal cardiovascular risk.

Premature live birth in a woman with antisynthetase syndrome following recurrent miscarriages

Antisynthetase syndrome (anti-SS) is a rare systemic autoimmune disease characterised by autoantibodies against aminoacyl-tRNA synthetases manifesting as one or more components of the classic triad: interstitial lung disease, arthritis and myositis. While it is well-recognised that autoimmune rheumatological disorders in general can contribute to multiple pregnancy complications, very little is known about how anti-SS itself affects pregnancy outcomes. Described here is the case of a 26-year-old pregnant woman with anti-SS whose pregnancy course was complicated by placental dysfunction and subsequent extremely premature delivery at 24 weeks' gestation. This report presents a review of the literature to date and discusses potential pregnancy complications associated with anti-SS and their subsequent targeted management.

Cognition and Cerebrovascular Reactivity in Midlife Women With History of Preeclampsia and Placental Evidence of Maternal Vascular Malperfusion

Background: Preeclampsia is emerging as a sex-specific risk factor for cerebral small vessel disease (SVD) and dementia, but the reason is unknown. We assessed the relationship of maternal vascular malperfusion (MVM), a marker of placental SVD, with cognition and cerebral SVD in women with and without preeclampsia. We hypothesized women with both preeclampsia and MVM would perform worst on information processing speed and executive function.

Methods: Women (n = 45; mean 10.5 years post-delivery; mean age: 41 years; 42.2% Black) were classified as preeclampsia-/MVM-, preeclampsia+/MVM-, or preeclampsia+/MVM+. Information processing speed, executive function, and memory were assessed. In a pilot sub-study of cerebrovascular reactivity (CVR; n = 22), cerebral blood flow during room-air breathing and breath-hold induced hypercapnia were obtained via arterial spin labeling MRI. Non-parametric tests and regression models were used to test associations.

Results: Between-group cognitive differences were significant for information processing speed (p = 0.02); preeclampsia+/MVM+ had the lowest scores. Cerebral blood flow increased from room-air to breath-hold, globally and in all regions in the three groups, except the preeclampsia+/MVM+ parietal region (p = 0.12). Lower parietal CVR (less change from room-air breathing to breath-holding) was correlated with poorer information processing speed (partial ρ = 0.63, p = 0.005) and executive function (ρ = 0.50, p = 0.03) independent of preeclampsia/MVM status.

Conclusion: Compared to women without preeclampsia and MVM, midlife women with both preeclampsia and MVM have worse information processing speed and may have blunted parietal CVR, an area important for information processing speed and executive function. MVM in women with preeclampsia is a promising sex-specific indicator of cerebrovascular integrity in midlife.

Placenta pathology in recipient versus donor oocyte derivation for in vitro fertilization in a setting of hypertensive disorders of pregnancy and IUGR

INTRODUCTION

Assisted reproductive technology including in vitro fertilization (IVF) and oocyte donation (OD) may increase risk for placenta-mediated diseases. Comprehensive analysis of histopathological placental lesions according to source of oocytes used in the IVF procedure - recipient derived (RD-IVF) vs oocyte donation (OD-IVF), has not been conducted in a population with a hypertensive disorder of pregnancy (HDP) and/or intrauterine growth restriction (IUGR).

METHODS

A retrospective cohort study of archived placenta specimens from RD-IVF and OD-IVF pregnancies affected by HDP and/or IUGR was conducted with blinded histopathological placental examination. Three categories of lesions were differentiated and defined as main outcomes: maternal vascular malperfusion (MVM), chronic inflammation, and fetal vascular malperfusion (FVM). To determine the relationship between conception method and placental lesions, multivariable regressions were performed with maternal age, gestational age, HDP, birth and placental weight percentiles as model covariates.

RESULTS

115 placentas were included 83 (72.2%) RD-IVF, 32 (27.8%) OD-IVF. Adjusted OR (aOR) for conception method was 5.05 (95%CI 0.58-43.90, p=0.142) for MVM, 1.87 (95%CI 0.68-5.15, p=0.228) for chronic inflammatory and 0.61 (95%CI 0.15-2.37, p=0.471) for FVM lesions. Multiple gestation demonstrated borderline association with MVM (aOR=0.24, 95%CI 0.04-1.51, p=0.129) and total pathology score (aRR=0.79, 95%CI 0.62-1.01, p=0.058). Subgroup analysis suggested greater odds of villitis of unknown etiology (VUE) for OD-IVF (aOR=2.98, 95%CI 1.12-7.93, p=0.029).

DISCUSSION

Source of oocyte derivation demonstrated no evidence of association with main outcomes in cases of HDP and/or IUGR. Subgroup analysis demonstrated increased rates of inflammatory lesions for OD-IVF. Multiple gestation may be associated with decreased MVM and total lesions.

Go Red for Women Strategically Focused Research Network: Summary of Findings and Network Outcomes

The Go Red for Women movement was initiated by the American Heart Association (AHA) in the early 2000s to raise awareness concerning cardiovascular disease (CVD) risk in women. In 2016, the AHA funded 5 research centers across the United States to advance our knowledge of the risks and presentation of CVD that are specific to women. This report highlights the findings of the centers, showing how insufficient sleep, sedentariness, and pregnancy-related complications may increase CVD risk in women, as well as presentation and factors associated with myocardial infarction with nonobstructive coronary arteries and heart failure with preserved ejection fraction in women. These projects were augmented by collaborative ancillary studies assessing the relationships between various lifestyle behaviors, including nightly fasting duration, mindfulness, and behavioral and anthropometric risk factors and CVD risk, as well as metabolomic profiling of heart failure with preserved ejection fraction in women. The Go Red for Women Strategically Focused Research Network enhanced the evidence base related to heart disease in women, promoting awareness of the female-specific factors that influence CVD.

CXCL12-CXCR4 Interplay Facilitates Palatal Osteogenesis in Mice

Cranial neural crest cells (CNCCs), identified by expression of transcription factor Sox9, migrate to the first branchial arch and undergo proliferation and differentiation to form the cartilage and bone structures of the orofacial region, including the palatal bone. Sox9 promotes osteogenic differentiation and stimulates CXCL12-CXCR4 chemokine-receptor signaling, which elevates alkaline phosphatase (ALP)-activity in osteoblasts to initiate bone mineralization. Disintegration of the midline epithelial seam (MES) is crucial for palatal fusion. Since we earlier demonstrated chemokine-receptor mediated signaling by the MES, we hypothesized that chemokine CXCL12 is expressed by the disintegrating MES to promote the formation of an osteogenic center by CXCR4-positive osteoblasts. Disturbed migration of CNCCs by excess oxidative and inflammatory stress is associated with increased risk of cleft lip and palate (CLP). The cytoprotective heme oxygenase (HO) enzymes are powerful guardians harnessing injurious oxidative and inflammatory stressors and enhances osteogenic ALP-activity. By contrast, abrogation of HO-1 or HO-2 expression promotes pregnancy pathologies. We postulate that Sox9, CXCR4, and HO-1 are expressed in the ALP-activity positive osteogenic regions within the CNCCs-derived palatal mesenchyme. To investigate these hypotheses, we studied expression of Sox9, CXCL12, CXCR4, and HO-1 in relation to palatal osteogenesis between E15 and E16 using (immuno)histochemical staining of coronal palatal sections in wild-type (wt) mice. In addition, the effects of abrogated HO-2 expression in HO-2 KO mice and inhibited HO-1 and HO-2 activity by administrating HO-enzyme activity inhibitor SnMP at E11 in wt mice were investigated at E15 or E16 following palatal fusion. Overexpression of Sox9, CXCL12, CXCR4, and HO-1 was detected in the ALP-activity positive osteogenic regions within the palatal mesenchyme. Overexpression of Sox9 and CXCL12 by the disintegrating MES was detected. Neither palatal fusion nor MES disintegration seemed affected by either HO-2 abrogation or inhibition of HO-activity. Sox9 progenitors seem important to maintain the CXCR4-positive osteoblast pool to drive osteogenesis. Sox9 expression may facilitate MES disintegration and palatal fusion by promoting epithelial-to-mesenchymal transformation (EMT). CXCL12 expression by the MES and the palatal mesenchyme may promote osteogenic differentiation to create osteogenic centers. This study provides novel evidence that CXCL12-CXCR4 interplay facilitates palatal osteogenesis and palatal fusion in mice.

Fibrinogen-Like Protein 2-Associated Transcriptional and Histopathological Features of Immunological Preeclampsia

Preeclampsia is a multifactorial hypertensive disorder of pregnancy, with variable presentation in both maternal and fetal factors, such that no treatment or marker is currently universal to all cases. Here, we demonstrate that the prothrombinase and immunomodulatory secreted factor FGL-2 (fibrinogen-like protein 2) is differentially expressed across previously characterized gene expression clusters containing clinically relevant disease subtypes. FGL2 is low in a cluster consistent with the traditional paradigm of the pathology of preeclampsia (canonical preeclampsia) and high in a cluster exhibiting evidence of immune activation (immunological preeclampsia). We show that it is part of an immunoregulatory gene module integral to the transcriptional profile and placental pathology specific to immunological preeclampsia. We determine that FGL2 associates positively with chronic inflammation lesions of the placenta while associating negatively with maternal vascular malperfusion lesions. The transcriptional profiles of maternal vascular malperfusion lesions show downregulation of FGL2 and upregulation of previously investigated preeclampsia biomarkers, such as FLT1 (Fms Related Receptor Tyrosine Kinase 1) and ENG (endoglin). Conversely, the profiles of chronic inflammation lesions show an interesting downregulation of these genes, but an upregulation of FGL2 and of FGL2-correlated immunoregulatory genes, suggesting it is upregulated downstream of major inflammatory mediators such as TNF (tumor necrosis factor)-α and IFN (interferon)-γ, hallmarks of the immunological preeclampsia subtype. This work, overall, demonstrates that FGL-2 expression levels in the term placenta reflect the unique pathophysiology that leads to immunological preeclampsia, leading to its potential as a subtype-specific biomarker.

Pivotal role of the transcriptional co-activator YAP in trophoblast stemness of the developing human placenta

Various pregnancy complications, such as severe forms of preeclampsia or intrauterine growth restriction, are thought to arise from failures in the differentiation of human placental trophoblasts. Progenitors of the latter either develop into invasive extravillous trophoblasts, remodeling the uterine vasculature, or fuse into multinuclear syncytiotrophoblasts transporting oxygen and nutrients to the growing fetus. However, key regulatory factors controlling trophoblast self-renewal and differentiation have been poorly elucidated. Using primary cells, three-dimensional organoids, and CRISPR-Cas9 genome-edited JEG-3 clones, we herein show that YAP, the transcriptional coactivator of the Hippo signaling pathway, promotes maintenance of cytotrophoblast progenitors by different genomic mechanisms. Genetic or chemical manipulation of YAP in these cellular models revealed that it stimulates proliferation and expression of cell cycle regulators and stemness-associated genes, but inhibits cell fusion and production of syncytiotrophoblast (STB)-specific proteins, such as hCG and GDF15. Genome-wide comparisons of primary villous cytotrophoblasts overexpressing constitutively active YAP-5SA with YAP KO cells and syncytializing trophoblasts revealed common target genes involved in trophoblast stemness and differentiation. ChIP-qPCR unraveled that YAP-5SA overexpression increased binding of YAP-TEAD4 complexes to promoters of proliferation-associated genes such as CCNA and CDK6 Moreover, repressive YAP-TEAD4 complexes containing the histone methyltransferase EZH2 were detected in the genomic regions of the STB-specific CGB5 and CGB7 genes. In summary, YAP plays a pivotal role in the maintenance of the human placental trophoblast epithelium. Besides activating stemness factors, it also directly represses genes promoting trophoblast cell fusion.

Pre-conception blood pressure and evidence of placental malperfusion

Background

Evidence of placental maternal vascular malperfusion is associated with significant perinatal outcomes such as preeclampsia, intrauterine growth restriction and preterm birth. Elevations in pre-pregnancy blood pressure increase the risk for poor perinatal outcomes; however, the evidence linking pre-pregnancy blood pressure and placental malperfusion is sparse.

Materials and methods

We conducted a retrospective case-control study of women with singleton gestations with placental evaluations who delivered at Magee-Womens Hospital in 2012. Charts from 100 deliveries with placental malperfusion lesions (vasculopathy, advanced villous maturation, infarct, or fibrin deposition) and 102 deliveries without placental malperfusion were randomly selected for screening. Blood pressure, demographic, and clinical data were abstracted from pre-pregnancy electronic medical records and compared between women with and without subsequent placental malperfusion lesions.

Results

Overall, 48% of women had pre-pregnancy records, and these were similarly available for women with and without placental malperfusion. Women with placental malperfusion demonstrated a reduction in their pre- to early pregnancy decrease in diastolic blood pressure (DBP). Adjusted for race, pre-pregnancy BMI, age, pre-conception interval, and gestational age at the first prenatal visit, the difference in pre- to early pregnancy DBP was significantly less in women with placental malperfusion compared to those without this pathologic finding (− 1.35 mmHg drop vs − 5.6mmg, p < 0.05).

Conclusion

A blunted early gestation drop in DBP may be a risk factor for placental malperfusion, perhaps related to early pregnancy vascular maladaptation. The ability of the electronic medical record to provide pre-pregnancy data serves as an underutilized approach to study pre-pregnancy health.

None, One, or Both Placentas Involved with Malperfusion Lesions in Twin Pregnancies Complicated by Preeclampsia-Does It Matter?

We aimed to study the association between the number of placentas with vascular malperfusion lesions in dichorionic twin pregnancies complicated by preeclampsia and the severity of the disease and pregnancy outcomes. Dichorionic twin pregnancies with preeclampsia (n = 125), from January 2007-June 2018, were reviewed. Affected placenta was defined as the presence of maternal/fetal vascular malperfusion lesions. Maternal demographics, pregnancy characteristics, and neonatal outcomes were compared between three groups: no pathological placentas, one pathological placenta, and two pathological placentas. Composite adverse neonatal outcome was defined as ≥ 1 early neonatal complication. Regression analysis models were used to recognize independent associations with the number of involved placentas. The two pathological placenta group (n = 57 pregnancies), the one pathological placenta group (n = 40 pregnancies), and the no pathological placenta group (n = 28 pregnancies) differed in terms of gestational age (GA) at delivery (p < 0.001, p = 0.008) and the rates of severe features (p = 0.028, p = 0.047). Neonates born to the two pathological placenta group (n = 114), the one pathological placenta group (n = 80), and the no pathological placenta group (n = 56) were characterized by lower birth weights (p < 0.001, p = 0.031), higher rates of small for gestational age (SGA) (p = 0.017, p = 0.748), neonatal intensive care unit admission (p = 0.004, p = 0.013), and composite adverse neonatal outcome (p < 0.001, p = 0.025). By regression analyses, the presence of two pathological placentas was found to be independently associated with severe features (aOR = 5.1), GA at delivery < 32 weeks (aOR = 2.0), SGA (aOR = 2.5), and composite adverse neonatal outcome (aOR = 2.7). In dichorionic twin pregnancies, there is an association between the presences of placental vascular malperfusion lesions in none, one, or both placentas and the development of early and severe preeclampsia, as well as with SGA and adverse neonatal outcome.

The Placenta as a Window to Maternal Vascular Health

Cardiovascular disease remains the leading killer of women, with sex-specific manifestation, mechanisms, and morbidity. Preeclampsia, fetal growth restriction, and a subset of preterm births demonstrate aberrancies in the maternal vessels supplying the placenta and damage to the placental parenchyma consistent with hypoxic/ischemic or oxidative injury. This constellation of findings, maternal vascular malperfusion (MVM) lesions, may hold the key to understanding and identifying the elevated risk for early cardiovascular disease in women who experience adverse pregnancy outcomes. This intriguing possibility has only begun to be examined, but accumulating evidence is compelling and is reviewed here.

Early pregnancy immune profile and preterm birth classified according to uteroplacental lesions

INTRODUCTION

Preterm birth is a heterogeneous phenotype, with placental abnormalities underlying many cases. The etiology of preterm births that occur in the absence of placental abnormalities, however, remain enigmatic and we considered that early pregnancy biomarkers may provide clues.

METHODS

Women from a hospital-based cohort (2008-2012, n = 397) were randomly selected within 6 strata of term and preterm birth with and without placental decidual vasculopathy (arteriopathy), intrauterine inflammation/infection (acute chorioamnionitis), or no lesions. Lipids and inflammatory markers were analyzed in first trimester samples (12.5 ± 0.6 weeks) and related to outcome groups (referent, term births with no lesions). Factor analysis then clustered analytes and related these to preterm birth groups, adjusted for covariates and stratified by pre-pregnancy obesity.

RESULTS

Three biomarker patterns were identified. Immune activation cytokines (33% of the variance) were associated with preterm birth with no lesions (aOR 1.5, 95%CI 1.1-2.1), particularly among obese women. In contrast, inflammatory chemokines (9% of variance) were associated with term and preterm vasculopathy among non-obese women (aOR 2.6 [1.3, 4.7] and 2.0 [1.1, 3.0], respectively).

DISCUSSION

The early pregnancy maternal immune profile is related to preterm births classified according to placental lesions, and these associations vary according to obesity status.

Placental and Fetal Effects of Onartuzumab, a Met/HGF Signaling Antagonist, When Administered to Pregnant Cynomolgus Monkeys

Onartuzumab is an engineered single arm, monovalent monoclonal antibody that targets the MET receptor and prevents hepatocyte growth factor (HGF) signaling. Knockout mice have clearly demonstrated that HGF/MET signaling is developmentally critical. A pre- and postnatal development study (enhanced design) was conducted in cynomolgus monkeys to evaluate the potential developmental consequences following onartuzumab administration. Control or onartuzumab, at loading/maintenance doses of 75/50 mg/kg (low) or 100/100 mg/kg (high), was administered intravenously once weekly to 12 confirmed pregnant female cynomolgus monkeys per group from gestation day (GD) 20 through GD 174. Onartuzumab administration resulted in decreased gestation length, decreased birth weight, and increased fetal and perinatal mortality. A GD147 C-section was conducted for a subset of Control and High Dose monkeys, and identified placental infarcts with hemorrhage in the chorionic plate, chorionic villus and/or decidual plate. These findings were limited to placentas from onartuzumab-treated animals. In addition, decreased cellularity of the hepatocytes with dilated hepatic sinusoids was inconsistently observed in the liver of a few fetal or infant monkeys that died in the perinatal period. Surviving offspring had some evidence of developmental delay compared with controls, but no overt teratogenicity. Overall, effects on the perinatal fetuses were consistent with those reported in knockout mice, but not as severe. Onartuzumab concentrations were low or below the level of detection in most offspring, with cord blood concentrations only 1%-2% of maternal levels on GD 147. Malperfusion secondary to onartuzumab-induced placental injury could explain the adverse pregnancy outcomes, fetal growth restriction and relatively low fetal exposures.

Human placenta and trophoblast development: key molecular mechanisms and model systems

Abnormal placentation is considered as an underlying cause of various pregnancy complications such as miscarriage, preeclampsia and intrauterine growth restriction, the latter increasing the risk for the development of severe disorders in later life such as cardiovascular disease and type 2 diabetes. Despite their importance, the molecular mechanisms governing human placental formation and trophoblast cell lineage specification and differentiation have been poorly unravelled, mostly due to the lack of appropriate cellular model systems. However, over the past few years major progress has been made by establishing self-renewing human trophoblast stem cells and 3-dimensional organoids from human blastocysts and early placental tissues opening the path for detailed molecular investigations. Herein, we summarize the present knowledge about human placental development, its stem cells, progenitors and differentiated cell types in the trophoblast epithelium and the villous core. Anatomy of the early placenta, current model systems, and critical key regulatory factors and signalling cascades governing placentation will be elucidated. In this context, we will discuss the role of the developmental pathways Wingless and Notch, controlling trophoblast stemness/differentiation and formation of invasive trophoblast progenitors, respectively.

High-mobility group box 1 at the time of parturition in women with gestational diabetes mellitus

PROBLEM

High-mobility group box 1 (HMGB1), a danger-associated molecular pattern marker, may indicate sterile inflammation through innate immune pathways. HMGB1 is implicated in hyperglycemia and excess glucose in trophoblast. Metabolic dysfunction and dyslipidemia are associated with gestational diabetes mellitus (GDM), but few studies examined associations between HMGB1 and GDM. We determined HMGB1 levels, and the ratio of HMGB1 to innate immune markers, in women with GDM at parturition.

METHOD OF STUDY

This case-control study of 50 GDM pregnancies and 100 healthy controls utilized data and plasma samples from PeriBank. HMGB1, pentraxin-3, and interleukin (IL)-6 were measured by ELISA. Logistic regression calculated odds ratios (OR) and 95% confidence intervals (CI) adjusting for age, pre-pregnancy body mass index, and type of labor.

RESULTS

There were no significant associations between HMGB1 and GDM. The ratio of HMGB1 to pentraxin-3 and IL-6 did not alter the odds of GDM. There was a significant statistical interaction between HMGB1 and maternal age (P = .02). When associations were examined by age groups, HMGB1 was associated with reduced odds of HMGB1 among women ≤25 (AOR = 0.007 CI 95% <0.001-0.3). Odds ratios increased as age increased (AOR range 1.2-3.8) but results were not statistically significant.

CONCLUSION

High-mobility group box 1 was not associated with GDM. However, we found evidence that maternal age was a potential effect modifier of the relationship between HMGB1 and GDM. As there is growing evidence that HMGB1 may play important roles in reproduction, future studies should explore maternal factors that may alter HMGB1 levels.

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

Preeclampsia is distinguishable from other hypertensive conditions of pregnancy by its high rates of decidual arteriopathy, the uterine type of chronic hypoxic placental injury, the occurrence of villous infarctions, and clusters of multinucleate trophoblasts in the maternal floor. To retrospectively study the clinical and placental phenotypes of 230 women with early-onset preeclampsia, 261 women with late-onset preeclampsia, and 5059 women without hypertension in pregnancy (comparative group), 24 clinical and 46 placental phenotypes were statistically compared (analysis of variance, χ² with Bonferroni correction). The frequency of decidual arteriopathy (both hypertrophic and atherosis), patterns of chronic hypoxic placental injury, villous infarction, membrane laminar necrosis, membrane microscopic chorionic pseudocysts, clusters of maternal floor multinucleated trophoblasts, excessive number of extravillous trophoblasts, and intervillous thrombi was strikingly higher in both late-onset preeclampsia and early-onset preeclampsia than in the comparative group without hypertension in pregnancy. All 3 patterns of chronic hypoxic placental injury were 2- to 3-fold more common in preeclampsia. Although the preuterine pattern was as common in early-onset preeclampsia as it was in late-onset preeclampsia, the postuterine pattern was 2-fold more common in early-onset preeclampsia, and chronic villitis of unknown etiology was more common in late-onset preeclampsia than in the other 2 groups. Features of shallow placental implantation occurred at the same frequency in early-onset preeclampsia as in late-onset preeclampsia, which reflects an underlying common pathological mechanism in both subgroups of preeclampsia, while hypoxic lesions and patterns of placental injury were more common in early-onset preeclampsia than in late-onset preeclampsia, which correlates with more severe clinical outcomes of the former.

Plasma concentrations of soluble endoglin in the maternal circulation are associated with maternal vascular malperfusion lesions in the placenta of women with preeclampsia

We evaluated the association between plasma soluble endoglin (sENG) and maternal vascular malperfusion (MVM) lesions of the placenta in women with preeclampsia. We measured sENG (sCD105) by ELISA in N = 70 women diagnosed with preeclampsia (median [IQR] GA at sampling = 36.4 [6.0] weeks) and available placental pathology. Placental pathology reports were reviewed for evidence of MVM based on the presence of ≥1 of the following: villous infarct, decidual vasculopathy, accelerated villous maturation, intervillous fibrin deposition, and/or low placental weight (<10th percentile for GA). We categorized plasma sENG concentrations into tertiles and used a modified Poisson regression approach to estimate the prevalence of MVM associated with sENG. We separately estimated the association between sENG and accelerated villous maturation, villous infarct, and low placental weight, the three most frequent lesions in the sample. We adjusted all models for age, parity, pre-pregnancy obesity, smoking, and infant sex. The prevalence of MVM in our sample of women with preeclampsia was 74%. Women in the highest sENG tertile had a higher prevalence of MVM (aPR[adjusted prevalence ratio] 1.70, 95% CI 1.15-2.52), low placental weight (aPR 3.26, 95% CI 1.25-8.50), and villous infarcts (aPR 2.93, 95% CI 1.27-6.73) compared with women in the lowest sENG tertile, after adjusting for covariates. Medium (aPR 2.57, 95% CI 1.17-5.66) and high (aPR 3.14, 95% CI 1.47-6.70) tertile concentrations of sENG were associated with higher accelerated villous maturation. Our results suggest that sENG may mark a more severe placental phenotype of preeclampsia, although findings should be replicated in larger cohorts.

More Maternal Vascular Malperfusion and Chorioamnionitis in Placentas After Expectant Management vs. Immediate Delivery in Fetal Growth Restriction at (Near) Term: A Further Analysis of the DIGITAT Trial

Objective: Management of late fetal growth restriction (FGR) is limited to adequate fetal monitoring and optimal timing of delivery. The Disproportionate Intrauterine Growth Intervention Trial At Term (DIGITAT) trial compared induction of labor with expectant management in pregnancies at (near) term complicated by suspected FGR. Findings of the DIGITAT trial were that expectant monitoring prolonged pregnancy for 10 days and increased birth weight with only 130 grams. This resulted in more infants born below the 2.3rd percentile compared to induction of labor, respectively, 12.5% in induction of labor and 30.6% in expectant monitoring group. The main placental lesions associated with FGR are maternal vascular malperfusion, fetal vascular malperfusion, and villitis of unknown etiology. We investigated whether placentas of pregnancies complicated with FGR in the expectant monitoring group reveal more and more severe pathology due to pregnancy prolongation. Material and methods: The DIGITAT trial was a multicenter, randomized controlled trial with suspected FGR beyond 36 + 0 weeks. We now analyzed all available cases (n = 191) for placental pathology. The macroscopic details were collected and histological slides were recorded and classified by a single perinatal pathologist, blinded for pregnancy details and outcome. The different placental lesions were scored based on the latest international criteria for placental lesions as defined in the Amsterdam Placental Workshop Group Consensus Statement. Results: The presence of maternal vascular malperfusion and chorioamnionitis were higher in the expectant management group (p < 0.05 and p < 0.01, respectively). No differences in placental weight and maturation of the placenta between the induction of labor and the expectant management group were seen. Fetal vascular malperfusion, villitis of unknown etiology and nucleated red blood cell count did not differ between the groups. Conclusion: Expectant management of late FGR is associated with increased maternal vascular malperfusion and chorioamnionitis. This may have implications for fetal and neonatal outcome, such as programming in the developing child influencing health outcomes later in life.

Placental findings in non-hypertensive term pregnancies and association with future adverse pregnancy outcomes: a cohort study

INTRODUCTION

Women with adverse pregnancy outcomes (APOs) have excess risk of later life cardiovascular disease (CVD) perhaps related to an underlying high-risk vascular phenotype. We sought to determine if placental evidence of maternal malperfusion in uncomplicated pregnancies is associated with an increased risk of APOs in subsequent pregnancies.

METHODS

536 women with more than one delivery and an initial uncomplicated pregnancy with placental pathology examination between 2008 and 2012 were included. APOs (small for gestational age, preterm delivery, or preeclampsia) were identified for each delivery. Multivariable log-binomial regression was used to estimate the risk of an APO in a subsequent pregnancy associated with MVM lesions in index pregnancy with adjustment for covariates.

RESULTS

Placental pathology from the initial pregnancy was compared between women with no APO in any pregnancy (-APO/-APO; n = 403) and women with an initial uncomplicated pregnancy and a subsequent adverse outcome (-APO/+APO; n = 133). Women with MVM lesions had an increased risk of an APO in a subsequent pregnancy relative to women with no MVM lesions after adjusting for covariates (aOR = 1.61; 95%CI = 1.06-2.46). Decidual vasculopathy was found in 13/133 (9.8%) of -APO/+APO women compared with 16/403 (4.0%) of -APO/-APO women, with an adjusted odds ratio of 2.51 (95% CI = 1.31-4.80).

DISCUSSION

MVM lesions found in placentas in uncomplicated pregnancies are associated with an increased risk of an adverse outcome in a subsequent pregnancy. Placental evidence of vascular malperfusion could offer a novel approach to risk stratification for subsequent pregnancy complications and perhaps future CVD.

The differences in placental pathology and neonatal outcome in singleton vs. twin gestation complicated by small for gestational age

OBJECTIVE

We aimed to compare placental histopathology and neonatal outcome between dichorionic diamniotic (DCDA) twins and singleton pregnancies complicated by small for gestational age (SGA).

METHODS

Medical files and placental pathology reports from all deliveries between 2008 and 2017 of SGA neonates, (birthweight < 10th percentile), were reviewed. Comparison was made between singleton pregnancies complicated with SGA (singletons SGA group) and DCDA twin pregnancies (Twins SGA group), in which only one of the neonates was SGA. Placental diameters were compared between the groups. Placental lesions were classified into maternal and fetal vascular malperfusion lesions (MVM and FVM), maternal (MIR) and fetal (FIR) inflammatory responses, and chronic villitis. Neonatal outcome parameters included composite of early neonatal complications.

RESULTS

The twins SGA group (n = 66) was characterized by a higher maternal age (p = 0.011), lower gestational age at delivery (34.9 ± 3.1 vs. 37.7 ± 2.6 weeks, p < 0.001), and a higher rate of preeclampsia (p = 0.010), compared to the singletons SGA group (n = 500). Adverse composite neonatal outcome was more common in the twins SGA group (p < 0.001). Placental villous lesions related to MVM (p < 0.001) and composite MVM lesions (p = 0.04) were more common in the singletons SGA group. On multivariate logistic regression analysis, the singletons SGA group was independently associated with placental villous lesions (aOR 3.6, 95% CI 1.9-7.0, p < 0.001) and placental MVM lesions (aOR 2.44, 95% CI 1.29-4.61, p = 0.006).

CONCLUSION

Placentas from SGA singleton pregnancies have more MVM lesions as compared to placentas from SGA twin pregnancies, suggesting different mechanisms involved in abnormal fetal growth in singleton and twin gestations.

Association between maternal/newborn genetic variants, placental pathology and spontaneous preterm birth risk: a Romanian population-based study

Objective: The objective of this study was to determine the association between maternal/newborn single-nucleotide polymorphisms (SNPs) in three candidate genes, placental pathology and the risk of spontaneous preterm birth (SPTB) in a Romanian population.Methods: We performed a prospective case-control study in a tertiary maternity in Romania, including 79 mother-newborn pairs with SPTB and 81 mother-newborn pairs with term delivery. Using real-time Polymerase Chain Reaction (PCR), three SNPs rs8192282 A > G, rs2277698 C > T and rs34003 A > C located on interleukin 6 receptor (IL6R), tissue inhibitor of matrix metalloproteinase-2 (TIMP2) and fibroblast growth factor 1 (FGF1) genes were assessed. The minor allele and genotype frequencies were compared between groups. Multilocus genetic association analyses were performed. From pathology reports, the morphological and histopathological examination of the placentas were extracted.Results: The rs34003 C/C genotype frequency in newborns FGF1 gene was significantly higher in the spontaneous preterm birth (SPTB) group compared to the control group (p = .045). In single-locus analyses, C/C genotype was associated with an increased risk of spontaneous preterm birth (OR = 2.59, 95%CI: 1.02-6.58). Additionally, this homozygote genotype was correlated with the presence of placental pathology, especially with the inflammatory and vascular lesions (p < .01). The prediction model based on rs34003 C/C genotype - placental pathology joint influence had a statistically significant regression coefficient (p < .01, OR = 7.76, 95%CI: 4.03-14.93). Single nucleotide polymorphisms related to IL6R gene in maternal samples and FGF1 gene in newborns were associated with spontaneous preterm delivery in multilocus genetic association analyses (p = .028, OR of 2.375).Conclusions: Our results indicate that rs34003 C/C genotype in newborns FGF1gene is correlated with the occurrence of placental pathological lesions and with an increased SPTB risk. The association of two SNPs in maternal and fetal genes doubled the risk of spontaneous preterm birth in our population.

The role of placental malperfusion in the pathogenesis of preeclampsia in dichorionic twin and singleton pregnancies

INTRODUCTION

In singletons, the pathogenesis of hypertensive disorders of pregnancy (HDP) is attributed to abnormal placentation, characterized by maternal vascular malperfusion (MVM) lesions. Whether MVM plays a similar role in twin pregnancies is unclear. The purpose of the study was to compared placental pathology findings between dichorionic-twin and singleton pregnancies complicated by HDP.

METHODS

Retrospective cohort study of women with dichorionic-twin or singleton pregnancies complicated by HDP who gave birth in a single tertiary center between 2001 and 2015. Placental abnormalities were classified into lesions associated with MVM, fetal vascular malperfusion, placental hemorrhage and chronic villitis. Placental findings and neonatal outcomes were compared between twin and singleton pregnancies.

RESULTS

A total of 144 women with twins and 768 women with a singleton pregnancy met the inclusion criteria. Compared with HDP singletons, twins with HDP had higher mean birth weights, were less likely to be small for gestational age and be born at <34 and at <32 weeks. Twins had lower odds for placental weight below <10th percentile (aOR 0.49, 95%CI 0.33-0.71), for MVM pathology (aOR 0.28, 95%CI 0.20-0.39) and for fetal vascular malperfusion pathology (aOR 0.65, 95%CI 0.45-0.93). These finding remained significant in the subpopulation of early onset HDP (<34 weeks) and small for gestational newborn.

DISCUSSION

Our findings support the hypothesis that MVM are less relevant to the pathogenesis of HDP in twin pregnancies and suggest that other placental or non-placental factors are responsible for the increased risk of HDP in twin pregnancies.

Forensic Aspects of Perinatal Deaths

From a forensic pathologist's perspective, there are several aspects of the perinatal postmortem that are particularly important. If a fetus is found abandoned, the pathologist needs to ascertain the fetal age, the appropriateness of growth, if the baby was born alive or dead, and the possible causes of death. In cases of litigation for perinatal deaths occurring in hospitals, access to the obstetric and neonatal notes (if the baby is born alive and dies a few hours or days later) is fundamental to reach a correct interpretation and conclusion. The most important points to consider in cases of intrapartum death are the roles of asphyxia and trauma in the causation of the baby's death. Timing of the fetal death in relation to delivery may also be an important point in these cases. Finally, intrapartum lesions should always be considered in the differential diagnosis of possible child abuse in babies aged two months or less.

[Pathoanatomical and clinical aspects of the placenta in preterm birth]

BACKGROUND

Prematurely born children show a clearly elevated risk for perinatal morbidity, long-term pediatric morbidities and development of chronic diseases in adulthood compared to babies born at term. The pathoanatomical investigation of placentas from preterm births is useful for assessing the etiology, the risk of recurrence and the prognosis for the child.

AIMS

The focus is on presenting the clinical and pathoanatomical characteristics of acute chorioamnionitis as a frequent cause of preterm induction of labor and pregnancy-induced hypertension, in particular preeclampsia as a frequent reason for elective cesarean section. Other lesions, sometimes of unclear etiology associated with preterm birth and substantially elevated risk of recurrence are reviewed. The clinical correlations and therapeutic options of the various diseases are discussed taking the risk of recurrence into consideration.

MATERIAL AND METHODS

Examination of placentas, association with the clinical course and a literature search.

RESULTS AND DISCUSSION

Acute chorioamnionitis and omphalovasculitis can be histologically subdivided into different stages which correlate with the clinical severity and the prognosis for the newborn child. Chronic deciduitis, chronic chorioamnionitis, villitis of unknown etiology, massive perivillous fibrin deposition and chronic histiocytic intervillositis are entities of unclear etiology associated with recurrent abortion and preterm birth. Autoimmune diseases and thrombophilia are occasionally associated with these pathologically defined lesions. Pregnancy-associated hypertensive disease and particularly preeclampsia as the cause of intrauterine developmental delay and elective cesarean section often show characteristic pathoanatomical placental lesions, which can give indications for the severity and duration of the disease and the prognosis for the child. Early onset (<34 weeks of gestation) and late onset preeclampsia show clinical and morphological differences. Subsequent pregnancies are classified as being at risk and screening for preeclampsia should be clinically performed.

3D R 2 * mapping of the placenta during early gestation using free-breathing multiecho stack-of-radial MRI at 3T

BACKGROUND

Multiecho gradient-echo Cartesian MRI characterizes placental oxygenation by quantifying R 2 * . Previous research was performed at 1.5T using breath-held 2D imaging during later gestational age (GA).

PURPOSE

To evaluate the accuracy and repeatability of a free-breathing (FB) 3D multiecho gradient-echo stack-of-radial technique (radial) for placental R 2 * mapping at 3T and report placental R 2 * during early GA.

STUDY TYPE

Prospective.

POPULATION

Thirty subjects with normal pregnancies and three subjects with ischemic placental disease (IPD) were scanned twice: between 14-18 and 19-23 weeks GA.

FIELD STRENGTH

3T.

SEQUENCE

FB radial.

ASSESSMENT

Linear correlation (concordance coefficient, ρ_c ) and Bland-Altman analyses (mean difference, MD) were performed to evaluate radial R 2 * mapping accuracy compared to Cartesian in a phantom. Radial R 2 * mapping repeatability was characterized using the coefficient of repeatability (CR) between back-to-back scans. The mean and spatial coefficient of variation (CV) of R 2 * was determined for all subjects, and separately for anterior and posterior placentas, at each GA range.

STATISTICAL TESTS

ρ_c was tested for significance. Differences in mean R 2 * and CV were tested using Wilcoxon Signed-Rank and Rank-Sum tests. P < 0.05 was considered significant. Z-scores for the IPD subjects were determined.

RESULTS

FB radial demonstrated accurate (ρ_c ≥0.996; P < 0.001; |MD|<0.2s^-1 ) and repeatable (CR<4s^-1 ) R 2 * mapping in a phantom, and repeatable (CR≤4.6s^-1 ) R 2 * mapping in normal subjects. At 3T, placental R 2 * mean ± standard deviation was 12.9s^-1  ± 2.7s^-1 for 14-18 and 13.2s^-1  ± 1.9s^-1 for 19-23 weeks GA. The CV was significantly greater (P = 0.043) at 14-18 (0.63 ± 0.12) than 19-23 (0.58 ± 0.13) weeks GA. At 19-23 weeks, the CV was significantly lower (P < 0.001) for anterior (0.49 ± 0.08) than posterior (0.67 ± 0.11) placentas. One IPD subject had a lower mean R 2 * than normal subjects at both GA ranges (Z<-2).

DATA CONCLUSION

FB radial provides accurate and repeatable 3D R 2 * mapping for the entire placenta at 3T during early GA.

LEVEL OF EVIDENCE

2 Technical Efficacy: Stage 1 J. Magn. Reson. Imaging 2019;49:291-303.

Oxidative stress in placental pathology

The most important function of the placenta is the exchange of nutrients and oxygen between a mother and her fetus. To establish a healthy functioning placenta, placentation needs to occur with adequate remodelling of spiral arteries by extravillous trophoblasts. When this process is impaired, the resulting suboptimal and inadequate placenta function results in the manifestation of pregnancy complications. Impaired placenta function can cause preeclampsia and leads to fetal growth restriction due to hypoxia. Presence of hypoxia leads to oxidative stress due to an imbalance between reactive oxygen species and antioxidants, thereby causing damage to proteins, lipids and DNA. In the placenta, signs of morphological adaptation in response to hypoxia can be found. Different placental lesions like maternal or fetal vascular malperfusion or chronic villitis lead to a decreased exchange of oxygen between the mother and the fetus. Clinically, several biomarkers indicative for oxidative stress, e.g. malondialdehyde and reduced levels of free thiols are found. This review aims to give an overview of the causes and (potential) role of placental oxidative stress in the development of placental parenchymal pathology and its clinical consequences. Also, therapeutic options aiming at prevention or treatment of hypoxia of the placenta and fetus are described.