Placental pathology is necessary to understand common pregnancy complications and achieve an improved taxonomy of obstetrical disease

Machine Learning Assessment of Gestational Age in Accelerated Maturation, Delayed Maturation, Villous Edema, Chorangiosis, and Intrauterine Fetal Demise

CONTEXT.—

Assessment of placental villous maturation is among the most common tasks in perinatal pathology. However, the significance of abnormalities in morphology is unclear and interobserver variability is significant.

OBJECTIVE.—

To develop a machine learning model of placental maturation across the second and third trimesters and quantify the impact of different pathologist-diagnosed abnormalities of villous morphology.

DESIGN.—

Digitize placental villous slides from more than 2500 placentas at 12.0 to 42.6 weeks. Build whole slide learning models to estimate obstetrician-determined gestational age for cases with appropriate maturation and normal morphology. Define the model output as "placental age" and compare it to the chronologic gestational age.

RESULTS.—

Our model showed an r2 of 0.864 and mean absolute error of 1.62 weeks for placentas with appropriate maturation in the test set. Pathologist diagnosis of accelerated maturation was associated with a 2.56-week increase in placental age (±2.91 weeks, P < .001), while delayed maturation was associated with a 0.92-week decrease in placental age (±1.82 weeks, P < .001). Intrauterine fetal demise causes diverse changes to placental age, driven by the nature of the demise. We tested the impact of training a model, using all live births. The resulting r2 was 0.874 and mean absolute error was 1.73 weeks. Furthermore, by including cases with abnormal maturation in the training data, the effect size of accelerated maturation was blunted to only 0.56 ± 2.35 weeks (P < .001).

CONCLUSIONS.—

We show that various abnormalities of villous maturation and morphology correlate with abnormalities in placental age. This "no pathologist" model could be useful in situations where pathologists are unavailable or the need for consistency outweighs the utility of expertise.

Histological Evidence of the Great Obstetrical Syndromes and Short-Term Neonatal Outcomes

OBJECTIVE

Great obstetrical syndrome (GOS) represents a group of pregnancy-related diseases that result in inadequate placentation. Most GOS cases end in preterm, either spontaneously or indicatively, and the use of antenatal corticosteroids (ACS) is inevitably discussed. The placenta is an important, transient fetal-derived organ and is the embodiment of maternal or fetal well-being. However, few studies provide histological evidence of the placenta in GOS. This study aims to address these issues.

METHODS

A total of 831 pregnant women were prospectively recruited. Placenta tissue was collected immediately and fixed with 4% paraformaldehyde solution for future H&E analysis. A novel checklist was devised to evaluate maternal vascular malperfusion sections on the basis of the commonly accepted Amsterdam placental workshop group consensus statement.

RESULTS

A total of 131 patients were classified as having GOS. Comparisons between those with and without GOS revealed significant differences, including higher levels of distal villous hypoplasia, increased syncytial knots, accelerated villous maturation, and higher total scores in GOS. We found significant negative associations between GOS and neonatal weight, neonatal height, head circumference, placental surface area, placental volume, and placenta gross examination score. GOS neonates were 1.25 times more likely to have hyperbilirubinemia. Regarding the effect of ACS, a significant reduction in birthweight, height, and head circumference was observed, along with an increased risk of hyperbilirubinemia.

CONCLUSION

This study provides histological evidence of the GOS that supports the defective deep placentation hypothesis. Our research also contributes to benefit-risk consultation in the GOS, such as in cases of PE and FGR, where a balance between fetal lung maturation and short-term neonatal outcomes is crucial.

Placental and Umbilical Cord Anomalies Detected by Ultrasound as Clinical Risk Factors of Adverse Perinatal Outcomes. Case Series Review of Selected Conditions. Part 3: Vascular Anomalies of the Umbilical Cord and Fetoplacental Vascular Malperfusion

In the previous published reviews Part 1 and Part 2, we examined the association between placental and umbilical cord anomalies in relation to adverse perinatal outcomes. In this conclusive Part 3, only umbilical cord vascular anomalies are considered, together with the perinatal effects caused by maternal vascular malperfusion and the secondary fetal vascular malperfusion anomalies. Specifically, the review comprises the following umbilical cord pathologies: umbilical cord torsion/stricture, amniotic band syndrome and umbilical cord strictures/strangulation, umbilical cord hemorrhagic cyst, umbilical cord rupture/cord hemangioma, umbilical cord hematoma, and umbilical cord ulceration. A series of case presentations and a gallery of images have been included to illustrate this final review.

Association Between Serum Uric Acid and Pregnancy Outcomes: A Study in Chinese Women

OBJECTIVE

The study aims to explore the relationship between serum uric acid (UA) levels in the first trimester and pregnancy outcomes.

METHODS

The clinical data of 1381 pregnant women who delivered in the Department of Obstetrics and Gynecology of Beijing Chao-Yang Hospital from June 2021 to July 2022 were collected. All patients were categorized into four groups (Q1-Q4) according to quartiles of UA, using the first quartile of UA as the reference group. Logistic regression analysis was used to observe the correlation between UA and pregnancy outcomes. Restricted cubic spline (RCS) was drawn to observe the dose-response relationship between UA and pregnancy outcomes.

RESULTS

The numbers of GDM patients in Q1-Q4 were 40 (11.70%), 46 (13.49%), 60 (17.29%) and 83 (23.65%), respectively (p < 0.001). Logistic regression analysis showed that higher quartiles of UA were significantly associated with an increased prevalence of gestational diabetes mellitus (GDM). After adjusting for confounding factors (maternal age, prepregnancy BMI, gestational weight gain, and gestational age), compared with the lowest quartile of UA, the highest quartile of UA had 2.06 times odds of GDM (OR, 2.06; 95% CI, 1.34, 3.18; p = 0.001) in Q4. RCS suggested that the risk of GDM increased slowly until UA levels reached 219.43 µmol/L and then began to increase rapidly afterward (overall p = 0.0037).

CONCLUSIONS

Increased uric acid concentrations in the first trimester are associated with an increased risk of GDM and gestational hypertension.

Delayed villous maturation with and without fetal demise: A case report of three successive pregnancies

This case study examined three subsequent pregnancies with delayed villous maturation (DVM) resulting in infants either large for gestational age (LGA) or appropriate for gestational age. A perinatal pathologist histopathologically reviewed the placentas using the Amsterdam Consensus Criteria. The first pregnancy ended in a term fetal demise of an LGA infant due to severe asphyxia associated with idiopathic DVM. Due to the history of stillbirth and DVM, labor was induced at 36 weeks of gestation in the second and third pregnancies. The second and third pregnancies resulted in liveborn infants with varying weight profiles despite similar placental lesions. All three placentas showed DVM with positive CD15 immunostaining. Additionally, the second and third placentas exhibited villitis of unknown etiology. This case report underscores the importance of structured histologic placental examination following complicated pregnancies by a perinatal pathologist.

Association of Deep Learning-Derived Histologic Features of Placental Chorionic Villi with Maternal and Infant Characteristics in the New Hampshire Birth Cohort Study

Introduction

Quantification of placental histopathological structures is challenging due to a limited number of perinatal pathologists, constrained resources, and subjective assessments prone to variability. Objective standardization of placental structure is crucial for easing the burden on pathologists, gaining deeper insights into placental growth and adaptation, and ultimately improving maternal and fetal health outcomes.

Methods

Leveraging advancements in deep-learning segmentation, we developed an automated approach to detect over 9 million placenta chorionic villi from 1,531 term placental whole slide images from the New Hampshire Birth Cohort Study. Using unsupervised clustering, we successfully identified biologically relevant villi subtypes that align with previously reported classifications - terminal, mature intermediate, and immature intermediate - demonstrating consistent size distributions and comparable abundance. We additionally defined tertile-based combinations of villi area and circularity to characterize villous geometry. This study applies these cutting-edge AI methods to quantify villi features and examine their association with maternal and infant characteristics, including gestational age at delivery, maternal age, and infant sex.

Results

Increasing gestational age at delivery was statistically significantly associated (p=0.003) with an increase in the proportion of mature intermediate villi and a decrease in the proportion of the smallest, most circular villi (p < 0.001). Maternal age and infant sex were not statistically significantly associated with measures of villous geometry.

Discussion

This work presents a workflow that objectively standardizes chorionic villi subtypes and geometry to enhance understanding of placental structure and function, while providing insights into the efficiency, growth, and the architecture of term placentas which can be used to inform future clinical care.

"The significance of clinical foetal autopsy for reproductive health care: an ethical analysis in the German context"

The clinical autopsy of foetuses, stillborn babies, or neonates and the examination of the placenta help to inform the mother's decision-making and her medical care for subsequent pregnancies. Indeed, these post-mortem examinations can identify unexpected congenital malformations or the cause of repeated miscarriage or stillbirth. However, the use of clinical pathology for diagnostic purposes in the context of family planning for bereaved parents with an unfulfilled desire to have a child, and IVF couples has received little attention to date. This article applies Beauchamp and Childress' bioethical framework to identify, assess and systematically discuss ethical issues associated with the use of clinical foetal autopsy in reproductive healthcare within the German legal context. In the format of a clinical ethics consultation, the article examines the current policy on perinatal post-mortem examinations in Germany, and asks whether the clinical foetal autopsy for reproductive health purposes should be part of standard clinical examinations offered to bereaved parents. The conclusion of our research recommends clinical foetal autopsy as ethically acceptable, provided that the necessary resources are available. This recommendation is based on the ethical obligation towards the mother as the patient, which is grounded in the bioethical principles of autonomy and beneficence.

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.

Stillbirth at term in Iceland: Causes of death and patterns of placental injury

BACKGROUND

Iceland is a high-income country with <400.000 inhabitants and low stillbirth rate (SBR). Increased antenatal risk assessment and interventions in high-risk pregnancies doubled the induction rate after 2008.

OBJECTIVE

Estimate the SBR at term, comparing an earlier (1996-2008) and latter (2009-2021) 13-year period, and describe causes of death and patterns of placental injury of infants stillborn at term.

STUDY DESIGN

Stillbirth at term was defined as antepartum or intrapartum death of an infant that was diagnosed after ≥37 weeks of gestation. All cases (n = 125) had placental examination. Histopathological slides were reviewed, and pattern of placental injury classified according to the Amsterdam consensus. Medical records were found for all mothers who had stillbirth at term and cause of death assigned according to the Stockholm classification of stillbirth.

RESULTS

No decrease in the SBR at term was found between periods. Majority of deaths (72 %) were caused by cord complications and/or placental insufficiency and deaths attributed to placental insufficiency increased in the latter period. Placentas weighing under the 10th percentile were more common in the latter period, 43.5 % vs. 30.2 % (p < 0.05) as was chronic villitis of unknown etiology (VUE), 40.3 % vs. 12.7 % (p < 0.01).

CONCLUSION

Stillbirth at term has not decreased in Iceland, despite increased antenatal surveillance and induction rate, with more deaths attributed to placental insufficiency and VUE increasingly found in the later period. Further research is needed on the correlation of patterns of placental injury with clinical phenotypes of mothers and infants.

Expression of Bax and Bcl-2 in the placenta from pre-term, term, and post-term deliveries: immunohistochemical analysis

The placenta is the most critical organ during pregnancy and its developmental status directly impacts fetal health. Placental dysfunction is associated with various pregnancy complications, including preterm birth, fetal growth restriction, and premature rupture of membranes (PROM). This study aimed to elucidate the expression changes of Bax and Bcl-2 and their association with pregnancy-related complications, providing new insights into placental dysfunction during pregnancy and offering a theoretical foundation for clinical diagnosis and prevention. The placental samples from 118 late pregnant women were retrospectively analyzed. They were assigned into pre-term, term, post-term, PROM, and non-PROM groups based on gestational age and the occurrence of PROM. Immunohistochemistry (IHC) staining was performed to gauge the Bax and Bcl-2 expressions in placenta. Receiver operating characteristic (ROC) curve was subsequently conducted to assess their associated with efficacy for PROM. The weight and volume of placentas in the pre-term group were sharply smaller to those in the term and post-term groups, with no apparent fibrosis or calcification observed. The term and post-term groups exhibited marked elevated Bax expression in the parturient group in contrast to the non-parturient group (P < 0.05), while there existed no substantial significance in Bcl-2 expression. The area under the curve (AUC) for Bax and Bcl-2 was 0.975 and 0.596, respectively, with a combined associated with value of 0.978, higher to single predictions. Bax and Bcl-2 expressions in late pregnancy placentas were associated with the onset of parturient status and PROM and their combined prediction exhibited accurate PROM predicted. These findings offered a new perspective for understanding the physiological and pathological changes of the placenta during pregnancy.

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..

Placental Abruption: Pathophysiology, Diagnosis, and Management

Placental abruption is a complete or partial separation of the placenta from the uterine decidua. Clinical manifestations include vaginal bleeding, abdominal pain, uterine contractions, and abnormalities in the fetal heart rate tracing. Placental abruption occurs in 0.4% to 1.0% of all pregnancies. However, the pathophysiology remains incompletely understood. We present a review of the pathophysiology, diagnosis, and management of placental abruption, exploring overlapping processes which contribute to premature placental separation. Classic findings and limitations of ultrasound in evaluating placental abruption are explained. Finally, we discuss the management of placental abruption based on gestational age, fetal status, and maternal hemodynamic stability.

The rapid diagnosis of intraamniotic infection with nanopore sequencing

BACKGROUND

Intraamniotic infection (defined as intraamniotic inflammation with microorganisms) is an important cause of the preterm labor syndrome. Methods for the detection of microorganisms in amniotic fluid are culture and/or polymerase chain reaction assay. However, both methods take time, and the results are rarely available for clinical decision-making. Nanopore sequencing technology offers real-time, long-read sequencing that can produce rapid results.

OBJECTIVE

To determine 1) the diagnostic performance of the 16S rDNA nanopore sequencing method for the identification of microorganisms in patients with intraamniotic inflammation and 2) the relationship between microbial burden and the intensity of the amniotic fluid inflammatory response.

STUDY DESIGN

We performed a prospective cohort study that included singleton pregnancies presenting with symptoms of preterm labor with intact membranes or of preterm prelabor rupture of the membranes. Amniotic fluid samples were obtained for the evaluation of bacteria in the amniotic cavity using cultivation and polymerase chain reaction-based 16S Sanger sequencing methods. Participants were classified into 4 groups according to the results of an amniotic fluid culture, 16S Sanger sequencing, and an amniotic fluid interleukin 6 concentration: 1) no intraamniotic infection and intraamniotic inflammation (interleukin 6 <2.6 ng/mL, and no microorganisms in the amniotic cavity, as determined by culture or 16S Sanger sequencing); 2) microbial invasion of the amniotic cavity without intraamniotic inflammation, defined by the presence of bacteria detected by culture or 16S Sanger sequencing; 3) sterile intraamniotic inflammation (interleukin 6 ≥2.6 ng/mL without microbial invasion of the amniotic cavity); and 4) intraamniotic infection (interkeukin 6 ≥2.6 ng/mL with microbial invasion of the amniotic cavity). Patients who underwent a mid-trimester amniocentesis, had no intraamniotic infection or intraamniotic inflammation, and delivered at term represented the control group. 16S rDNA nanopore sequencing was performed and the diagnostic indices for the identification of intraamniotic infection were determined. Bioinformatic analysis was carried out to identify microorganisms, and a read count of at least 100 or a read count exceeding that of the background species from the control group, along with a relative abundance of no less than 1%, was used.

RESULTS

1) The 16S nanopore sequencing had a sensitivity of 88.9% (8/9), specificity of 95.4% (41/43), positive predictive value of 80.0% (8/10), negative predictive value of 97.6% (41/42), positive likelihood ratio of 19.1 (95% confidence interval, 4.8-75.4), negative likelihood ratio of 0.1 (95% confidence interval, 0.02-0.7), and an accuracy of 94.2% (49/52) for the identification of intraamniotic infection (prevalence, 17% [9/52]); 2) the microbial load determined by the 16S nanopore sequencing had a strong positive correlation with the intensity of an intraamniotic inflammatory response (amniotic fluid interleukin 6 concentration; Spearman's correlation 0.9; P=.002); and 3) a subgroup of patients with intraamniotic inflammation did not have bacteria determined by culture, Sanger sequencing, or nanopore 16S, thus confirming the existence of sterile intraamniotic inflammation.

CONCLUSION

The 16S nanopore sequencing has high diagnostic indices, predictive values, likelihood ratios, and accuracy in the diagnosis of intraamniotic infection.

Placental Pathology and Blood Pressure at Age 7: A Longitudinal Discordant Twin Analysis

BACKGROUND

Evidence suggests that the intrauterine environment shapes offspring cardiovascular disease risk. Although placental dysfunction may be an important pathophysiologic pathway, numerous parental and pregnancy characteristics that influence offspring blood pressure are strong confounders of the mechanistic role of the placenta in observational analyses of singletons. Therefore, we leverage twin- and sibling-based comparison designs to determine whether placental pathology is associated with offspring blood pressure at age 7 while mitigating major sources of confounding.

METHODS

Data are from pregnant participants and their offspring in the Collaborative Perinatal Project, a longitudinal pregnancy cohort conducted from 1959 to 1965 in the United States. After delivery, placentas were systematically examined for lesions indicative of maternal vascular malperfusion (MVM) and acute inflammation. Blood pressure was assessed at a follow-up research visit when the offspring were 7 years old. Linear fixed-effects models were used to estimate associations between within-twin or sibling discordance in placental pathology and differences in blood pressure at age 7.

RESULTS

Overall, 193 twin pairs were eligible for inclusion, and 23.3% had placentas discordant for MVM. In a fixed-effect analysis, a twin with high-grade MVM had a higher systolic blood pressure Z score by 0.56 SDs than their co-twin without MVM (95% CI, 0.06-1.05) or a 5.7-mm Hg difference (95% CI, 0.6-10.8). Associations were consistent in a sensitivity analysis restricted to dichorionic twins and in a secondary analysis of 759 MVM-discordant sibling pairs. Acute placental inflammation was not associated with blood pressure at age 7.

CONCLUSIONS

MVM in the placenta is associated with higher offspring blood pressure in mid-childhood, independent of parental and pregnancy characteristics that twins have in common. The findings support the role of the placenta and the intrauterine environment in the developmental origins of cardiovascular health.

Priority Setting Partnership on Placental Pathology: Consensus recommendations for placental research

INTRODUCTION

The placenta supports the metabolic and respiratory requirements of the fetus. Placental disorders, caused by various pathophysiological mechanisms, may result in adverse pregnancy and neonatal outcomes. Knowledge gaps remain in the understanding, reporting and interpretation of placental pathology relating to clinical conditions. This project aimed to collaboratively identify the most important unanswered research questions related to placental pathology.

METHODS

An international Priority Setting Partnership (PSP) was conducted, involving (perinatal) pathologists, obstetricians, paediatrician-neonatologists, midwives, and scientists with expertise in placental pathology. In the first survey, participants identified their three most important unanswered research questions. Afterwards literature was reviewed for evidence on the proposed questions. In a second survey, participants ranked the most important questions from an initial long-list. The top-ranked questions were then discussed and finalized in a 1-h online consensus workshop.

RESULTS

Ninety participants completed the first survey. The majority of stakeholders were perinatal pathologists (n = 39 (43.3 %) and most were based in Europe (n = 43 (47.8 %). 270 questions were submitted; after review, these were subdivided into 32 overarching questions. The second ranking survey was completed by 53 participants. Twenty-five participants attended the online workshop, which reached consensus on the top 10. The questions focus, among others, on causes, recurrence risk, consistency of reporting, diagnosing tools and potential use of artificial intelligence.

DISCUSSION

Following this international PSP, the top 10 prioritized research questions on placental pathology have been identified. This will inform the research agenda for funders and policy-makers, and is intended to improve care for patients suffering from placental insufficiency.

The 36-week preeclampsia risk by the Fetal Medicine Foundation algorithm is associated with fetal compromise following induction of labor

BACKGROUND

Previous studies demonstrated that placental dysfunction leads to intrapartum fetal distress, particularly when an abnormal pattern of angiogenic markers is demonstrated at 36 weeks of gestation. The prediction of intrapartum fetal compromise is particularly important in patients undergoing induction of labor because of different indications for delivery, as this can be a useful in optimizing the method and timing of induction of labor.

OBJECTIVE

This study aimed to examine whether the risk of preeclampsia assessed using the Fetal Medicine Foundation algorithm (derived from a combination of maternal risk factors, mean arterial pressure, placental growth factor, and soluble fms-like tyrosine kinase-1) is associated with the risk of intrapartum fetal compromise requiring cesarean delivery in a population of patients with singleton pregnancies undergoing induction of labor for various indications.

STUDY DESIGN

This was a retrospective analysis on prospectively collected data from women with singleton pregnancies who underwent routine assessments at 35 0/7 to 36 6/7 weeks of gestation at King's College Hospital (London, United Kingdom). The study outcome was the rate of fetal compromise requiring cesarean delivery, examined in relation to the risk of preeclampsia assessed at 36 weeks of gestation using the Fetal Medicine Foundation risk model. Patients who underwent spontaneous labor and prelabor cesarean deliveries were excluded. In addition, 5 risk categories for preeclampsia were created on the basis of the Fetal Medicine Foundation 36-week risk model: A (≥1/2), B (<1/2- ≥1/5), C (<1/5- ≥1/20), D (<1/20-≥1/50), and E (<1/50). Based on the reason for induction of labor, we created 5 categories: premature rupture of membranes, postterm pregnancy (˃41 weeks of gestation), preeclampsia, fetal growth restriction (estimated fetal weight of ˂5th percentile), and preeclampsia and fetal growth restriction. A multinomial logistic regression was used to assess the risk of fetal compromise across the Fetal Medicine Foundation risk categories, accounting for all delivery outcomes (spontaneous or operative vaginal delivery and urgent cesarean delivery for fetal compromise, failure to progress, or other reasons) and allowing accurate and generalizable risk assessment of fetal compromise.

RESULTS

Of 45,375 pregnant women, 26,597 (58.6%) had spontaneous onset of labor, 6529 (14.0%) underwent elective prelabor cesarean delivery, which were excluded from the analysis. A total of 12,249 pregnant women were included, of which 182 had birth at ≤37 weeks of gestation and 1444 had fetal compromise (crude risk of 11.8%). The rate of vaginal delivery in the study population was 69.4%. The rates of fetal compromise in the 5 induction categories were 9.7% for premature rupture of membranes, 13.5% for postterm pregnancy, 14.8% for preeclampsia, 17.2% for fetal growth restriction, and 23.4% for preeclampsia and fetal growth restriction. Cases with intrapartum fetal compromise had a higher mean preeclampsia risk than cases without intrapartum fetal compromise (1/45 vs 1/81, respectively; P<.001). The risk of cesarean delivery for fetal compromise increased with (1) advancing gestational age (each week increase at 35-40 weeks: +1%; at 41-42 weeks: +5%), (2) nulliparity (+7%-10%) vs multiparity, (3) higher Fetal Medicine Foundation risk of preeclampsia (from the low-risk category of <1/50 to the high-risk category of ≥1/2: +18%; with greater effect for higher preeclampsia risk). In this study population, the rates of fetal compromise were lower with diagnoses of preeclampsia and rupture of membranes and higher with fetal growth restriction (alone or in combination with preeclampsia) and postterm pregnancy.

CONCLUSION

Our study highlights the clinical use of the Fetal Medicine Foundation 36-week PE risk model in determining the risk of fetal compromise requiring cesarean delivery after induction of labor. The same model can be combined with standard obstetric indications to induction of labour to establish the risk of fetal compromise requiring cesarean delivery. Therefore, the Fetal Medicine Foundation 36-week PE risk model can be used to optimize induction of labor.

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.

Long-term subculture induces syncytialization and influent the response to bisphenol A (BPA) of placental JEG-3 cells

The placenta is a temporary organ that exists only during pregnancy, responsible for connecting the mother and the fetus. During placental development, the cytotrophoblast cells differentiate into multinucleated, syncytialized cells that envelop the chorionic villi, a process known as syncytialization. These syncytiotrophoblast cells serve as a barrier between maternal circulation and the fetus and secrete important hormones such as human chorionic gonadotropin (hCG), estrogen, and progesterone. Proper regulation of trophoblast differentiation and hormone secretion is crucial throughout pregnancy, as disruption of these processes can lead to pregnancy failure. Previous studies showed that Bisphenol A (BPA), an endocrine-disrupting chemical (EDC), negatively impacts pregnancy. It affects placental development, tissue morphology, hormone secretion, and probably increase the risk of pregnancy complications. Furthermore, some compounds like hCG and forskolin induce the cell differentiation and affecting hormone secretion in trophoblast. In this study, we found that long-term subculture of JEG-3 cells indicates an increase in cell differentiation, alterations in physiological properties, and changes in hormone secretion profiles. Our results also demonstrate distinct responses in JEG-3 cells to BPA stimulation in later passages, suggesting that long-term subculture alters cell characteristics and elicits varied responses to stimuli. This implies potential harm from BPA exposure at different stages of pregnancy, albeit through different mechanisms.

Incorporating placental pathology into clinical care and research

Despite recent standardization of placental evaluation and establishment of criteria for diagnosis of major patterns of placental injury, placental pathological examination remains undervalued and under-utilized. The placenta can harbor a significant amount of information relevant to both the pregnant person and offspring. Placental pathology can also provide a significant context for pathophysiological study of adverse pregnancy outcomes, helping to optimally subcategorize the 'great obstetric syndromes' of pre-eclampsia (PE), spontaneous preterm birth (sPTB), and fetal growth restriction (FGR), and to identify causes of stillbirth. We hereby propose that placental evaluation should be incorporated into routine delivery of obstetric and neonatal care, and further suggest that its integration into clinical, translational, and basic research could significantly advance our understanding of pregnancy complications and adverse neonatal outcomes.

Epigenetic biomarker for preeclampsia-associated preterm birth and potential preventative medicine

Preterm birth (PTB) has dramatically increased within the population (i.e. >10%) and preeclampsia is a significant sub-category of PTB. Currently, there are no practical clinical parameters or biomarkers which predict preeclampsia induced PTB. The current study investigates the potential use of epigenetic (DNA methylation) alterations as a maternal preeclampsia biomarker. Non-preeclampsia term births were compared to preeclampsia PTBs to identify DNA methylation differences (i.e. potential epigenetic biomarker). Maternal buccal cell cheek swabs were used as a marker cell for systemic epigenetic alterations in the individuals, which are primarily due to environmentally induced early life or previous generations impacts, and minimally impacted or associated with the disease etiology or gestation variables. A total of 389 differential DNA methylation regions (DMRs) were identified and associated with the presence of preeclampsia. The DMRs were genome-wide and were predominantly low CpG density (<2 CpG/100 bp). In comparison with a previous PTB buccal cell epigenetic biomarker there was a 15% (60 DMR) overlap, indicating that the majority of the DMRs are unique for preeclampsia. Few previously identified preeclampsia genes have been identified, however, the DMRs had gene associations in the P13 K-Akt signaling pathway and metabolic gene family, such as phospholipid signaling pathway. Preliminary validation of the DMR use as a potential maternal biomarker used a cross-validation analysis on the samples and provided 78% accuracy. Although prospective expanded clinical trials in first trimester pregnancies and clinical comparisons are required, the current study provides the potential proof of concept a preeclampsia epigenetic biomarker may exist. The availability of a preeclampsia PTB maternal susceptibility biomarker may facilitate clinical management and allow preventative medicine approaches to identify and treat the preeclampsia condition prior to its occurrence.

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.

Identification of transcriptional signature change and critical transcription factors involved during the differentiation of mouse trophoblast stem cell into maternal blood vessel associated trophoblast giant cell

The placenta is essential organ for oxygen and nutrient exchange between the mother and the developing fetus. Trophoblast lineage differentiation is closely related to the normal function of the placenta. Trophoblast stem cells (TSCs) can differentiate into all placental trophoblast subtypes and are widely used as in vitro stem cell models to study placental development and trophoblast lineage differentiation. Although extensive research has been conducted on the differentiation of TSCs, the possible parallels between trophoblast giant cells (TGCs) that are differentiated from TSCs in vitro and the various subtypes of TGC lineages in vivo are still poorly understood. In this study, mouse TSCs (mTSCs) were induced to differentiate into TGCs, and our mRNA sequencing (RNA-seq) data revealed that mTSCs and TGCs have distinct transcriptional signatures. We conducted a comparison of mTSCs and TGCs transcriptomes with the published transcriptomes of TGC lineages in murine placenta detected by single-cell RNA-seq and found that mTSCs tend to differentiate into maternal blood vessel-associated TGCs in vitro. Moreover, we identified the transcription factor (TF) ZMAT1, which may be responsible for the differentiation of mTSCs into sinusoid TGCs, and the TFs EGR1 and MITF, which are likely involved in the differentiation of mTSCs into spiral artery-associated TGCs. Thus, our findings provide a valuable resource for the mechanisms of trophoblast lineage differentiation and placental deficiency-associated diseases development.

Pathologic findings of the placenta and clinical implications - recommendations for placental examination

The placenta is a unique and complex organ that combines the circulatory systems of two or more individuals within a single dynamic organ with a set, short lifespan. A diverse spectrum of disorders, including infections as well as metabolic, genetic, circulatory, and maturation defects, may affect its function. Pathology investigation of the placenta is key for identifying several pathogenic processes in both the mother and the foetus. Aberrant placentation, maternal and foetal vascular compromise, infection, inflammatory immunologic conditions, and disorders of maturation are elements of newly proposed classification schemes. The clinical impact of placental examination consists of diagnosing maternal and foetal disease, identifying the potential for recurrence, correlating clinical pathological findings with distinct morphologic features, and identifying the aetiology responsible for growth restriction or foetal death. Gestational trophoblastic disease occurs more frequently in the first trimester; however, in very rare cases, it can affect the term or third-trimester placenta. The application of reproducible nomenclature is expected to facilitate progress in the diagnosis and treatment of obstetric and foetal disorders with placental manifestation. Therefore, this review aims to facilitate communication between obstetricians, neonatologists, and pathologists involved in this diagnostic process.

[Fetal death: Expert consensus from the College of French Gynecologists and Obstetricians]

Fetal death is defined as the spontaneous cessation of cardiac activity after fourteen weeks of amenorrhea. In France, the prevalence of fetal death after 22 weeks is between 3.2 and 4.4/1000 births. Regarding the prevention of fetal death in the general population, it is not recommended to counsel for rest and not to prescribe vitamin A, vitamin D nor micronutrient supplementation for the sole purpose of reducing the risk of fetal death (Weak recommendations; Low quality of evidence). It is not recommended to prescribe aspirin (Weak recommendation; Very low quality of evidence). It is recommended to offer vaccination against influenza in epidemic periods and against SARS-CoV-2 (Strong recommendations; Low quality of evidence). It is not recommended to systematically look for nuchal cord encirclements during prenatal screening ultrasounds (Strong Recommendation; Low Quality of Evidence) and not to perform systematic antepartum monitoring by cardiotocography (Weak Recommendation; Very Low Quality of Evidence). It is not recommended to ask women to perform an active fetal movement count to reduce the risk of fetal death (Strong Recommendation; High Quality of Evidence). Regarding evaluation in the event of fetal death, it is suggested that an external fetal examination be systematically offered (Expert opinion). It is recommended that a fetopathological and anatomopathological examination of the placenta be carried out to participate in cause identification (Strong Recommendation. Moderate quality of evidence). It is recommended that chromosomal analysis by microarray testing be performed rather than conventional karyotype, in order to be able to identify a potentially causal anomaly more frequently (Strong Recommendation, moderate quality of evidence); to this end, it is suggested that postnatal sampling of the placental fetal surface for genetic purposes be preferred (Expert Opinion). It is suggested to test for antiphospholipid antibodies and systematically perform a Kleihauer test and a test for irregular agglutinins (Expert opinion). It is suggested to offer a summary consultation, with the aim of assessing the physical and psychological status of the parents, reporting the results, discussing the cause and providing information on monitoring for a subsequent pregnancy (Expert opinion). Regarding announcement and support, it is suggested to announce fetal death without ambiguity, using simple words and adapting to each situation, and then to support couples with empathy in the various stages of their care (Expert opinion). Regarding management, it is suggested that, in the absence of a situation at risk of disseminated intravascular coagulation or maternal vitality, the patient's wishes should be taken into account when determining the time between the diagnosis of fetal death and induction of birth. Returning home is possible if it's the patient wish (Expert opinion). In all situations excluding maternal life-threatening emergencies, the preferred mode of delivery is vaginal delivery, regardless the history of cesarean section(s) history (Expert opinion). In the event of fetal death, it is recommended that mifepristone 200mg be prescribed at least 24hours before induction, to reduce the delay between induction and delivery (Low recommendation. Low quality of evidence). There are insufficient data in the literature to make a recommendation regarding the route of administration (vaginal or oral) of misoprostol, neither the type of prostaglandin to reduce induction-delivery time or maternal morbidity. It is suggested that perimedullary analgesia be introduced at the start of induction if the patient asks, regardless of gestational age. It is suggested to prescribe cabergoline immediately in the postpartum period in order to avoid lactation, whatever the gestational age, after discussing the side effects of the treatment with the patient (Expert opinion). The risk of recurrence of fetal death after unexplained fetal death does not appear to be increased in subsequent pregnancies, and data from the literature are insufficient to make a recommendation on the prescription of aspirin. In the event of a history of fetal death due to vascular issues, low-dose aspirin is recommended to reduce perinatal morbidity, and should not be combined with heparin therapy (Low recommendation, very low quality of evidence). It is suggested not to recommend an optimal delay before initiating another pregnancy just because of the history of fetal death. It is suggested that the woman and co-parent be informed of the possibility of psychological support. Fetal heart rate monitoring is not indicated solely because of a history of fetal death. It is suggested that delivery not be systematically induced. However, induction can be considered depending on the context and parental request. The gestational age will be discussed, taking into account the benefits and risks, especially before 39 weeks. If a cause of fetal death is identified, management will be adapted on a case-by-case basis (expert opinion). In the event of fetal death occurring in a twin pregnancy, it is suggested that the surviving twin be evaluated as soon as the diagnosis of fetal death is made. In the case of dichorionic pregnancy, it is suggested to offer ultrasound monitoring on a monthly basis. It is suggested not to deliver prematurely following fetal death of a twin. If fetal death occurs in a monochorionic twin pregnancy, it is suggested to contact the referral competence center, in order to urgently look for signs of acute fetal anemia on ultrasound in the surviving twin, and to carry out weekly ultrasound monitoring for the first month. It is suggested not to induce birth immediately.

Placental pathological findings and their association with maternal and fetal clinical outcomes: A cross-sectional study

Background

Placental pathological changes can occur in both normal and high-risk pregnancies, leading to adverse maternal and neonatal outcomes.

Objective

This study aimed to investigate the relationship between placental histopathological findings and maternal and fetal clinical outcomes, as well as to determine if there is an association between maternal comorbidities and placental pathologies.

Materials and Methods

In this study, 250 placenta samples were evaluated. The slides and paraffin blocks were retrieved from the archive of the pathology department of Shariati and Yas hospitals, Tehran, Iran. The placental histopathological findings were analyzed in relation to maternal and fetal clinical data.

Results

The average age of pregnant women was 31.84 yr. The average gestational age at birth was 28 wk. The most prevalent pathological finding was maternal vascular malperfusion, observed in 59.6% of cases. The presence of nucleated red blood cells (NRBC) in umbilical cord blood vessels was observed in 16.4% of cases. Fetal vascular malperfusion was significantly associated with intrauterine fetal demise. Maternal inflammatory response was associated with premature rupture of membranes. Maternal vascular malperfusion and the presence of NRBC in umbilical cord blood vessels was significantly associated with pre-eclampsia and preterm labor. Furthermore, a history of maternal malignancy was associated with placental infarction and the presence of NRBC in umbilical cord blood vessels.

Conclusion

The findings of this study underscore the importance of evaluating placental histopathological findings in relation to maternal and fetal clinical outcomes. Therefore, understanding these placental pathological changes will be crucial in predicting and preventing complications in subsequent pregnancies.

Intrauterine Fetal Demise, Spontaneous Abortion and Congenital Cytomegalovirus: A Systematic Review of the Incidence and Histopathologic Features

The objective was to review the existing literature reporting on spontaneous abortion (SA) and intrauterine fetal demise (IUFD) associated with cytomegalovirus (CMV) infection. A review using standardized terminology such as 'intrauterine fetal death', 'congenital cytomegalovirus' and 'CMV' was performed using PubMed and Embase (Medline) using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) methodology. Twenty-one studies met inclusion criteria. CMV was identified as a potential or likely factor in a median of 7.1% of SA or IUFD in study cohorts. Of the studies, 11 used fetal remains, 18 used placenta, 6 used serum, and 1 used post-mortem dried blood spot as specimens for testing for CMV. Features commonly observed were fetal thrombotic vasculopathy, hydrops fetalis and chronic villitis. CMV is frequently noted in studies evaluating viral etiologies of SA or IUFD. Large population-based studies are needed to estimate the incidence of CMV-associated SA or IUFD. CMV and congenital CMV should be included on the differential diagnosis in all cases of SA or IUFD of unknown etiology.

Reduced syncytin-1 regulates trophoblast invasion and apoptosis in preeclampsia

INTRODUCTION

Preeclampsia is a pregnancy-specific disorder characterized by de novo development of hypertension and proteinuria over 20 weeks gestation that has been associated with the dysfunction of trophoblasts. Current evidence suggests that syncytin-1 plays an important role in the non-fusogenic biological activity of trophoblasts, except for specific fusogenic function. However, the underlying mechanism remains unclear.

METHODS

The expression and location of syncytin-1 in normal and the late-onset preeclampsia placentas were detected by quantitative real-time PCR, western blotting and immunofluorescence. Morphological and apoptosis analysis were processed in placentas. The ex vivo extravillous explant culture model was used to explore the effect of syncytin-1 on EVT outgrowths. Real-time quantitative PCR and immunoblotting were used to calculate syncytin-1 levels in the trophoblast cells before and after syncytin-1 knockdown or overexpression. CCK-8 assay was used to detect the cell viability. TUNEL staining and immunoblotting were processed in trophoblast cells. Transwell assays and wound healing assays were utilize to assess the invasion and migration of trophoblastic cells. Conditional knockout of syncytin-a mouse model was conducted to present the change of placentas in vivo. The ex vivo extravillous explant culture model was used to explore the effect of syncytin-1 on EVT outgrowths. Western blotting was used to identify the key proteins of PI3K/Akt pathways and invasion-related proteins in trophoblast cells.

RESULTS AND DISCUSSION

Here, reduced syncytin-1 was identified in the late-onset preeclampsia placentas. Reduced syncytin-1 may attenuates the EMT process by promoting apoptosis, inhibiting proliferation and invasion by suppressed PI3K/Akt pathway in trophoblast cells. Our findings provide novel insights into the non-fusogenic biological function of reduced syncytin-1 that may be involves in the pathogenesis of preeclampsia.

Predictors of spontaneous pregnancy loss in single ventricle physiology

BACKGROUND

Pregnant patients with single ventricle (SV) physiology carry a high risk of spontaneous pregnancy loss (SPL), yet the clinical factors contributing to this risk are not well defined.

METHODS

Single-centre retrospective study of pregnant patients with SV physiology seen in cardio-obstetrics clinic over the past 20 years with chart review of their obstetric history. Patients without a known pregnancy outcome were excluded. Univariable Bayesian panel-data random effects logit was used to model the risk of SPL.

RESULTS

The study included 20 patients with 44 pregnancies, 20 live births, 21 SPL and 3 elective abortions. All had Fontan palliation except for two with Waterston and Glenn shunts. 10 (50%) had a single right ventricle (RV). 14 (70%) had moderate or severe atrioventricular valve regurgitation (AVVR). Atrial arrhythmias were present in 16 (80%), Fontan-associated liver disease (FALD) in 15 (75%) and FALD stage 4 in 9 (45%). 12 (60%) were on anticoagulation. Average first-trimester oxygen saturation was 93.8% for live births and 90.8% for SPL. The following factors were associated with higher odds of SPL: RV morphology (OR 1.72 (95% credible interval (CrI) 1.0008-2.70)), moderate or severe AVVR (OR 1.64 (95% CrI 1.003-2.71)) and reduced first-trimester oxygen saturation (OR 1.83 (95% CrI 1.03-2.71) for each per cent decrease in O2 saturation.

CONCLUSION

Pregnant patients with SV physiology, particularly those with RV morphology, moderate or severe AVVR, and lower first-trimester oxygen saturations, have a higher risk of SPL. Identifying these clinical risk factors can guide preconception counselling by the cardio-obstetrics team.

Placental chronic inflammatory histopathology and fetal growth in a cohort with universal placental examination

INTRODUCTION

Chronic placental inflammation is a routinely diagnosed group of placental lesions that reflect immunologic dysfunction of the mother, fetus, or both.

METHODS

Complete placental pathology examinations were performed for all term births at New York Presbyterian- Brooklyn Methodist Hospital from January 2010-August 2016. Diagnoses were blinded except to gestational age. CPI lesions were marked as chronic choriodeciduitis, decidual plasma cells, chronic inflammation of basal plate with anchoring villitis, and chronic villitis.

RESULTS

In this cohort of term pregnancies, 257 (11.6 %) males and 218 (9.8 %) females had ≥1 CPI lesions. Chronic villitis was the most common (319 or 14 %), with chronic choriodeciduitis, decidual plasma cells, and chronic inflammation of basal plate with anchoring villitis in 94 (4 %), 69 (3 %) and 170 (8 %), respectively. In males, chronic villitis was associated with lower gestational adjusted birthweight and had no association with placental weight. In females, chronic villitis was associated with lower gestational adjusted birthweight, but the effect became nonsignificant after adjustment for placental weight.

DISCUSSION

In summary, CPI lesions' incidence and association with birth weight vary by sex. Chronic villitis is associated with lower birthweight in females; this effect is completely mediated by placental weight. Chronic villitis showed a weak direct association of chronic villitis in males, but no association with lower placental weight in males. We suggest that differences between our results and previous publications reflect effects of sampling bias.

Umbilical-portal-systemic venous shunt and intrauterine growth restriction: an inquiry from a prospective study

BACKGROUND

The investigation of the fetal umbilical-portal venous system is based on the premise that congenital anomalies of this system may be related to adverse perinatal outcomes. Several small retrospective studies have reported an association between umbilical-portal-systemic venous shunts and intrauterine growth restriction. However, the prevalence of portosystemic shunts in the fetal growth restricted population is yet to be determined.

OBJECTIVE

The aims of this study were (1) to determine the prevalence of fetal umbilical-portal-systemic venous shunts in pregnancies complicated by intrauterine growth restriction and (2) to compare the perinatal and neonatal outcomes of pregnancies with intrauterine growth restriction with and without umbilical-portal-systemic venous shunts.

STUDY DESIGN

This was a prospective, cross-sectional study of pregnancies diagnosed with intrauterine growth restriction, as defined by the Society for Maternal-Fetal Medicine intrauterine growth restriction guidelines. All participants underwent a detailed anomaly scan, supplemented with a targeted scan of the fetal portal system. Venous shunts were diagnosed using color Doppler mode. The perinatal outcomes of pregnancies with intrauterine growth restriction with and without umbilical-portal-systemic venous shunts were compared.

RESULTS

A total of 150 cases with intrauterine growth restriction were recruited. The prevalence of umbilical-portal-systemic venous shunts in our cohort was 9.3% (n=14). When compared with the control group (intrauterine growth restriction without umbilical-portal-systemic venous shunts, n=136), the study group had a significantly lower mean gestational age at the time of intrauterine growth restriction diagnosis (29.7±5.6 vs 32.47±4.6 weeks of gestation; P=.036) and an earlier gestational age at delivery (33.50±6.0 vs 36.13±2.8; P=.005). The study group had a higher rate of fetal death (21.4% vs 0.7%; P<.001) and, accordingly, a lower rate of live births (71.4% vs 95.6%; P=.001). Additional associated fetal vascular anomalies were significantly more prevalent in the study group than in the control group (35.7% vs 4.4%; P≤.001). The rate of other associated anomalies was similar. The study group had a significantly lower rate of abnormal uterine artery Doppler indices (0% vs 40.4%; P=.011) and a higher rate of abnormal ductus venosus Doppler indices (64.3% vs 23%; P=.001). There were no cases of hypertensive disorders of pregnancy in the study group, whereas the control group had an incidence of 12.5% (P=.16). Other perinatal and neonatal outcomes were comparable.

CONCLUSION

Umbilical-portal-systemic venous shunt is a relatively common finding among fetuses with growth restriction. When compared with pregnancies with intrauterine growth restriction with a normal portal system, these pregnancies complicated by intrauterine growth restriction and an umbilical-portal-systemic venous shunt are associated with a different Doppler flow pattern, an increased risk for fetal death, earlier presentation of intrauterine growth restriction, a lower gestational age at delivery, additional congenital vascular anomalies, and a lower rate of pregnancy-induced hypertensive disorders. Meticulous sonographic evaluation of the portal system should be considered in the prenatal workup of intrauterine growth restriction, as umbilical-portal-systemic venous shunts may affect perinatal outcomes.

Neonatal Encephalopathy is a Complex Phenotype Representing Reproductive and Pregnancy Exposome Effects on the Maternal-Placental-Fetal Triad

Reproductive, pregnancy, and placental exposomes influence the fetal neural exposome through toxic stressor interplay, impairing the maternal-placental-fetal (MPF) triad. Neonatal encephalopathy represents different clinical presentations based on complex time-dependent etiopathogenetic mechanisms including hypoxia-ischemia that challenge diagnosis and prognosis. Reproductive, pregnancy, and placental exposomes impair the fetal neural exposome through toxic stressor interplay within the MPF triad. Long intervals often separate disease onset from phenotype. Interdisciplinary fetal-neonatal neurology training, practice, and research closes this knowledge gap. Maintaining reproductive health preserves MPF triad health with life-course benefits.

Enhancing the Diagnostic Accuracy of Placental Pathology by Using the Amsterdam Consensus Criteria

Background and objective Standardizing placental pathology diagnoses is crucial for improving diagnostic accuracy and clinical communication. The Amsterdam Consensus Criteria were developed to address inconsistencies in diagnosing significant placental pathologies. This study aimed to assess the application and effectiveness of the Amsterdam Consensus Criteria in diagnosing placental pathologies, with a focus on improving the reliability and precision of placental pathology reports. Methods A retrospective review of 100 consecutively archived placental pathology samples was performed at a tertiary care hospital. These samples, gathered from January through December 2021, were reassessed according to the Amsterdam criteria. The revised diagnoses were then compared with the original descriptive diagnoses. Results Significant changes were noted in all principal diagnoses, including maternal vascular malperfusion (MVM), fetal vascular malperfusion (FVM), chronic villitis of unknown etiology (VUE), and acute chorioamnionitis (ACA). This evaluation led to a recategorization of several cases. Frequently, parenchymal infarcts were reported without adequate information to ascertain their association with MVM. Additionally, there was a noticeable lack of understanding of FVM and VUE among pathologists. ACA was the condition most consistently documented. However, detailed grading and staging were often not included. Conclusions Our findings emphasize the need to use standardized diagnostic criteria, such as the Amsterdam criteria, to enhance diagnostic accuracy and facilitate communication between pathologists and clinicians. This will ultimately lead to improved patient care outcomes. It also underlines the necessity of continuous education and calibration for pathologists to mitigate interobserver variability. There is a demand to modify these criteria to ensure universal applicability and relevance in various clinical settings.

A case series of chorioangiomas in placentas with clinical indication for histological examination

Chorioangiomas are benign angiomas arising from chorionic tissue and they are the most common non-trophoblastic tumors of the placenta, as they are observed in 1% of all placentas examined. Most chorioangiomas are small and asymptomatic, often undetected during a prenatal ultrasound, and their clinical significance is still unknown. Large chorioangiomas, measuring more than 4-5 cm in diameter, can usually be detected prenatally by gray-scale or color Doppler sonography, and may be associated with maternal or fetal complications, such as preeclampsia, maternal mirror syndrome, preterm delivery, nonimmune fetal hydrops, fetal growth restriction and fetal demise. We herein describe the clinical-pathological features of a monocentric series of 30 placental chorioangiomas and discuss their clinical-pathological features and possible molecular mechanisms underlying their development.

Predictive Value of the sFlt-1/PlGF Ratio and Interleukin-6 for the Presence of Placental Lesions in Spontaneous Preterm Labor with Intact Membranes with Delivery within 7 Days

INTRODUCTION

The aim of the study was to identify predictive values of the soluble fms-like tyrosine kinase/placental growth factor (sFlt-1/PlGF) ratio and interleukin (IL)-6, assessed with a clinically available method in a large-volume biochemistry laboratory, in maternal blood, amniotic fluid, and umbilical cord blood for the presence of the placental lesions consistent with maternal vascular malperfusion (MVM) and acute histological chorioamnionitis (HCA), respectively.

METHODS

This retrospective study included 92 women with preterm labor with intact membranes (PTL) delivered within 7 days of admission with gestational ages between 22+0 and 34+6 weeks. The sFlt-1/PlGF ratio and IL-6 were assessed in stored samples of maternal serum, amniotic fluid, and umbilical cord serum using Elecsys® sFlt-1, PlGF, and IL-6 immunoassays.

RESULTS

Women with MVM had a higher sFlt-1/PlGF ratio in the maternal serum, compared to those without MVM (19.9 vs. 4.6; p < 0.0001), but not in the amniotic fluid or umbilical cord blood. A cut-off value of 8 for the sFlt-1/PlGF ratio in maternal serum was identified as optimal for predicting MVM in patients with PTL. Women with HCA had higher concentrations of IL-6 in maternal serum, compared to those without HCA (11.1 pg/mL vs. 8.4 pg/mL; p = 0.03), amniotic fluid (9,216 pg/mL vs. 1,423 pg/mL; p < 0.0001), and umbilical cord blood (20.7 pg/mL vs. 10.7 pg/mL, p = 0.002). Amniotic-fluid IL-6 showed the highest predictive value. A cut-off value of IL-6 concentration in the amniotic fluid of 5,000 pg/mL was found to be optimal for predicting HCA in PTL.

CONCLUSION

Maternal serum sFlt-1/PlGF and amniotic fluid IL-6 concentrations can be used for liquid biopsy to predict placental lesions in women with PTL who deliver within 7 days.

Interdisciplinary fetal-neonatal neurology training improves brain health across the lifespan

Integrated fetal, neonatal, and pediatric training constitute an interdisciplinary fetal-neonatal neurology (FNN) program. A dynamic neural exposome concept strengthens curriculum content. Trainees participate in mentoring committee selection for guidance during a proposed two-year program. Prenatal to postnatal clinical learning re-enforces early toxic stressor interplay that influences gene-environment interactions. Maternal-placental-fetal triad, neonatal, or childhood diseases require diagnostic and therapeutic decisions during the first 1,000 days when 80 % of neural connections contribute to life-course phenotypic expression. Pediatric follow-up through 3 years adjusts to gestational ages of preterm survivors. Cumulative reproductive, pregnancy, pediatric and adult exposome effects require educational experiences that emphasize a principle-to-practice approach to a brain capital strategy across the lifespan. More rigorous training during fetal, neonatal, and pediatric rotations will be offered to full time trainees. Adult neurology residents, medical students, and trainees from diverse disciplines will learn essential topics during time-limited rotations. Curriculum content will require periodic re-assessments using educational science standards that maintain competence while promoting creative and collaborative problem-solving. Continued career-long learning by FNN graduates will strengthen shared healthcare decisions by all stakeholders. Recognition of adaptive or maladaptive neuroplasticity mechanisms requires analytic skills that identify phenotypes associated with disease pathways. Developmental origins and life-course concepts emphasize brain health across the developmental-aging continuum, applicable to interdisciplinary research collaborations. Social determinants of health recognize diversity, equity, and inclusion priorities with each neurological intervention, particularly for those challenged with disparities. Diagnostic and therapeutic strategies must address resource challenges particularly throughout the Global South to effectively lower the worldwide burden of neurologic disease. Sustainable development goals proposed by the World Health Organization offer universally applicable guidelines in response to ongoing global and regional polycrises. Gender, race, ethnicity, and socio-economic equality promote effective preventive, rescue and reparative neuroprotective interventions. Global synergistic efforts can be enhanced by establishing leadership within academic teaching hubs in FNN training to assist with structure and guidance for smaller healthcare facilities in each community that will improve practice, education and research objectives. Reduced mortality with an improved quality of life must prioritize maternal-pediatric health and well-being to sustain brain health across each lifespan with transgenerational benefits.

Clinical Significance of the Large Fetal Vessel Lesions in Placental Fetal Vascular Malperfusion

Fetal vascular malperfusion (FVM) is an important pattern of placental injury. Although the significance of distal villous FVM (clusters of sclerotic and/or mineralized chorionic villi) is well documented, the clinical significance of proximal (large vessel) lesions of FVM is less clear, which is the aim of this retrospective analysis. To evaluate the clinical significance and placental associations of single and coexisting categories of lesions of large vessel FVM, 24 clinical and 44 placental phenotypes of 804 consecutive placentas with at least 1 lesion of proximal vessel FVM from the second half of pregnancy, divided according to the type or category of the individual FVM lesion (fetal vascular ectasia, fetal vascular thrombi, intramural fibrin deposition, and stem vessel obliteration): 689, 341, 286, and 267 placentas, respectively (first analysis) and single or coexisting large fetal vessel lesions (1, 2, 3, and 4 coexisting categories of lesions: 276, 321, 162, and 45 placentas, respectively) were statistically compared (analysis of variance, χ2, univariate analysis). Because of multiple comparisons, Bonferroni-corrected P < .001 was used as a threshold of statistical significance. In this population of high-risk pregnancies dominated by fetal congenital anomalies, single individual or 1 to 2 coexisting categories of lesions of the large vessel FVM, including fetal vascular thrombi, did not consistently correlate with clinical or placental variables and were not prognostically useful, but the coexistence of 3 or 4 lesions was associated with the most advanced gestational age, fetal congenital anomalies, distal villous FVM, particularly high-grade, chorangioma or chorangiomatosis, hypercoiled umbilical cord, perivascular stem edema, and marginate or vallate placenta. Therefore, the finding of multiple lesions of the large vessel FVM not only merits a diligent search for the distal villous lesions including the CD34 immunostaining, but also justifies putting the large vessel (global) FVM on the final placental diagnosis line, which in the case of up to only 2 lesions may not be justified.

Placental inflammatory injury induced by chlorinated polyfluorinated ether sulfonate (F-53B) through NLRP3 inflammasome activation

Chlorinated polyfluorinated ether sulfonate, commercially known as F-53B, has been associated with adverse birth outcomes. However, the reproductive toxicology of F-53B on the placenta remains poorly understood. To address this gap, we examined the impact of F-53B on placental injury and its underlying molecular mechanisms in vivo. Pregnant C57BL/6 J female mice were randomly allocated to three groups: the control group, F-53B 0.8 µg/kg/day group, and F-53B 8 µg/kg/day group. After F-53B exposure through free drinking water from gestational day (GD) 0.5-14.5, the F-53B 8 µg/kg/day group exhibited significant increases in placental weights and distinctive histopathological alterations, including inflammatory cell infiltration, heightened syncytiotrophoblast knots, and a loosened trophoblastic basement membrane. Within the F-53B 8 µg/kg/day group, placental tissue exhibited increased apoptosis, as indicated by increased caspase3 activation. Furthermore, F-53B potentially induced the NF-κB signaling pathway activation through IκB-α phosphorylation. Subsequently, this activation upregulated the expression of inflammatory cytokines and components of the NLRP3 inflammasome, including activated caspase1, IL-1β, IL-18, and cleaved gasdermin D (GSDMD), ultimately leading to pyroptosis in the mouse placenta. Our findings reveal a pronounced inflammatory injury in the placenta due to F-53B exposure, suggesting potential reproductive toxicity at concentrations relevant to the human population. Further toxicological and epidemiological investigations are warranted to conclusively assess the reproductive health risks posed by F-53B.

Clinical value of placental examination for paediatricians

The placenta contains valuable clinical information that is linked to fetal development, neonatal morbidity and mortality, and future health outcomes. Both gross inspection and histopathological examination of the placenta may identify intrinsic or secondary placental lesions, which can contribute directly to adverse neonatal outcomes or indicate the presence of an unfavourable intrauterine environment. Placental examination therefore forms an essential component of the care of high-risk neonates and at perinatal post-mortem examination. In this article, we describe the clinical value of placental examination for paediatricians and perinatal clinicians. We discuss common pathological findings on general inspection of the placenta with photographic examples and provide an overview of the placental pathological examination, including how to interpret key findings. We also address the medico-legal and financial implications of placental examinations and describe current and future clinical considerations for clinicians in regard to placental examination.

Severe COVID-19 in pregnant women: Analysis of placental features and perinatal outcomes

OBJECTIVES

Changes in placental features, such as maternal and fetal vascular malperfusion, are associated with SARS-CoV-2 infection. The anatomopathologic study of the placenta is crucial for understanding pregnancy and fetal complications. To that end, this study aimed to describe placental features and analyze the association between placental findings and perinatal outcomes in a cohort of pregnant women with severe COVID-19.

METHODS

This nested study within a prospective cohort study consisted of 121 singleton pregnant women with a diagnosis of severe COVID-19. Placental pathologic findings were described, and the associations between severe COVID-19 and clinical parameters and perinatal outcomes were assessed.

RESULTS

The prevalence of maternal vascular malperfusion was 52.1%, followed by fetal vascular malperfusion at 21.5%, ascending intrauterine infections at 11.6%, and inflammatory lesions at 11.6%. Other lesions were observed in 39.7% of the placentas examined. Inflammatory lesions were an independent factor (P = .042) in 5-minute Apgar scores below 7. Ascending infection was associated with fetal death (P = .027).

CONCLUSIONS

Maternal vascular malperfusion was the most prevalent placental feature in patients with severe COVID-19. Chorangiosis is associated with poor perinatal outcomes.

Association of Placental Pathology with Physical and Neuronal Development of Infants: A Narrative Review and Reclassification of the Literature by the Consensus Statement of the Amsterdam Placental Workshop Group

The placenta is the largest fetal organ, which connects the mother to the fetus and supports most aspects of organogenesis through the transport of nutrients and gases. However, further studies are needed to assess placental pathology as a reliable predictor of long-term physical growth or neural development in newborns. The Consensus Statement of the Amsterdam Placental Workshop Group (APWGCS) on the sampling and definition of placental lesions has resulted in diagnostic uniformity in describing the most common pathological lesions of the placenta and contributed to the international standardization of descriptions of placental pathology. In this narrative review, we reclassified descriptions of placental pathology from previously published papers according to the APWGCS criteria and comparatively assessed the relationship with infantile physical and/or neural development. After reclassification and reevaluation, placental pathology of maternal vascular malperfusion, one of the APWGCS criteria, emerged as a promising candidate as a universal predictor of negative infantile neurodevelopmental outcomes, not only in term and preterm deliveries but also in high-risk groups of very low birthweight newborns. However, there are few studies that examined placental pathology according to the full categories of APWGCS and also included low-risk general infants. It is necessary to incorporate the assessment of placental pathology utilizing APWGCS in the design of future birth cohort studies as well as in follow-up investigations of high-risk infants.

Baicalein improves the symptoms of polycystic ovary syndrome by mitigating oxidative stress and ferroptosis in the ovary and gravid placenta

BACKGROUND

Polycystic ovary syndrome is a metabolic and hormonal disorder that is closely linked to oxidative stress. Within individuals diagnosed with PCOS, changes occur in the ovaries, resulting in an excessive buildup of iron and peroxidation of lipids, both of which may be associated with the occurrence of ferroptosis. Baicalein, a flavonoid found in the roots of Scutellaria baicalensis and widely known as Chinese skullcap, is known for its anti-inflammatory and anti-ferroptotic properties, which protect against various diseases. Nevertheless, there has been no investigation into the impact of baicalein on polycystic ovary syndrome.

PURPOSE

This study aimed to correlate ferroptosis with polycystic ovary syndrome and to assess the effects of baicalein on ovarian dysfunction and placental development in pregnant patients.

STUDY DESIGN AND METHODS

Polycystic ovary syndrome was induced in a rat model through the administration of dehydroepiandrosterone, and these rats were treated with baicalein. Oxidative stress and inflammation levels were assessed in serum and ovaries, and tissue samples were collected for histological and protein analyses. Furthermore, different groups of female rats were mated with male rats to observe pregnancy outcomes and tissue samples were obtained for histological, protein, and RNA sequencing. Then, RNA sequencing of the placenta was performed to determine the key genes involved in ferroptosis negative regulation (FNR) signatures.

RESULTS

Baicalein was shown to reduce ovarian oxidative stress and pathology. Baicalein also ameliorated polycystic ovary syndrome by decreasing lipid peroxidation and chronic inflammation and modulating mitochondrial functions and ferroptosis in the ovaries. Specifically, glutathione peroxidase and ferritin heavy chain 1 were considerably downregulated in polycystic ovary syndrome gravid rats compared to their expression in the control group, and most of these differences were reversed after baicalein intervention.

CONCLUSIONS

Our findings, initially, indicated that baicalein could potentially enhance the prognosis of individuals suffering from polycystic ovary syndrome by reducing oxidative stress and ferroptosis, thus potentially influencing the formulation of a therapeutic approach to address this condition.

Mapping cell-to-tissue graphs across human placenta histology whole slide images using deep learning with HAPPY

Accurate placenta pathology assessment is essential for managing maternal and newborn health, but the placenta's heterogeneity and temporal variability pose challenges for histology analysis. To address this issue, we developed the 'Histology Analysis Pipeline.PY' (HAPPY), a deep learning hierarchical method for quantifying the variability of cells and micro-anatomical tissue structures across placenta histology whole slide images. HAPPY differs from patch-based features or segmentation approaches by following an interpretable biological hierarchy, representing cells and cellular communities within tissues at a single-cell resolution across whole slide images. We present a set of quantitative metrics from healthy term placentas as a baseline for future assessments of placenta health and we show how these metrics deviate in placentas with clinically significant placental infarction. HAPPY's cell and tissue predictions closely replicate those from independent clinical experts and placental biology literature.

Placental pathology and neonatal morbidity: exploring the impact of gestational age at birth

AIM

To evaluate placental pathology in term and post-term births, investigate differences in clinical characteristics, and assess the risk of adverse neonatal outcome.

METHODS

This prospective observational study included 315 singleton births with gestational age (GA) > 36 weeks + 6 days meeting the local criteria for referral to placental histopathologic examination. We applied the Amsterdam criteria to classify the placentas. Births were categorized according to GA; early-term (37 weeks + 0 days to 38 weeks + 6 days), term (39 weeks + 0 days to 40 weeks + 6 days), late-term (41 weeks + 0 days to 41 weeks + 6 days), and post-term births (≥ 42 weeks + 0 days). The groups were compared regarding placental pathology findings and clinical characteristics. Adverse neonatal outcomes were defined as 5-minute Apgar score < 7, umbilical cord artery pH < 7.0, admission to the neonatal intensive care unit or intrauterine death. A composite adverse outcome included one or more adverse outcomes. The associations between placental pathology, adverse neonatal outcomes, maternal and pregnancy characteristics were evaluated by logistic regression analysis.

RESULTS

Late-term and post-term births exhibited significantly higher rates of histologic chorioamnionitis (HCA), fetal inflammatory response, clinical chorioamnionitis (CCA) and transfer to neonatal intensive care unit (NICU) compared to early-term and term births. HCA and maternal smoking in pregnancy were associated with adverse outcomes in an adjusted analysis. Nulliparity, CCA, emergency section and increasing GA were all significantly associated with HCA.

CONCLUSIONS

HCA was more prevalent in late and post-term births and was the only factor, along with maternal smoking, that was associated with adverse neonatal outcomes. Since nulliparity, CCA and GA beyond term are associated with HCA, this should alert the clinician and elicit continuous intrapartum monitoring for timely intervention.

Endocrine-disrupting compounds and their impact on human placental function: evidence from placenta organ-on-chip studies

The effects of endocrine-disrupting compounds (EDCs) on the placenta, a critical gestational organ for xenobiotic protection, are well reported; however, models to determine the role of EDCs in placental disruption are limited. An advanced 2nd-trimester human placenta organ-on-chip model (2TPLA-OOC) was developed and validated, with six representative cells of the maternal and the fetal interface interconnected with microchannels. Various EDCs (150 ng mL-1 each of bisphenol A, bisphenol S, and polybrominated diphenyl ethers-47 and -99) were gradually propagated across the chip for 72 hours, and their various effects were determined. Cigarette smoke extract (CSE), an environmental risk factor, was used as a positive control. EDCs produced overall oxidative stress in the placental/decidual cells, induced cell-specific endocrine effects, caused limited (<10%) apoptosis/necrosis in trophoblasts and mesenchymal cells, induced localized inflammation but an overall anti-inflammatory shift, did not change immune cell migration from stroma to decidua, and did not affect placental nutrient transport. Overall, (1) the humanized 2TPLA-OOC recreated the placental organ and generated data distinct from the trophoblast and other cells studied in isolation, and (2) at doses associated with adverse pregnancies, EDCs produced limited and localized insults, and the whole organ compensated for the exposure.

Stillbirth and the placenta

Stillbirth affects a large proportion of pregnancies world-wide annually and continues to be a major public health concern. Several causes of stillbirth have been identified and include obstetrical complications, placental abnormalities, fetal malformations, infections, and medical complications in pregnancy. Placental abnormalities such as placental abruption, chorioangioma, vasa previa, and umbilical cord abnormalities have been identified as causes of death for a significant proportion of stillbirths. In the absence of placental abnormalities, the gross and histologic changes in the placenta in stillbirth are found when secondary to other etiologies. Here we describe both gross and histologic changes of the placenta that are associated with stillbirth.