Placental pathology, perinatal death, neonatal outcome, and neurological development: a systematic review

Morphological evaluation of the feline placenta correlates with gene expression of vascular growth factors and receptors†

Placental angiogenesis is critical for normal development. Angiogenic factors and their receptors are key regulators of this process. Dysregulated placental vascular development is associated with pregnancy complications. Despite their importance, vascular growth factor expression has not been thoroughly correlated with placental morphologic development across gestation in cats. We postulate that changes in placental vessel morphology can be appreciated as consequences of dynamic expression of angiogenic signaling agents. Here, we characterized changes in placental morphology alongside expression analysis of angiogenic factor splice variants and receptors throughout pregnancy in domestic shorthair cats. We observed increased vascular and lamellar density in the lamellar zone during mid-pregnancy. Immunohistochemical analysis localized the vascular endothelial growth factor A (VEGF-A) receptor KDR to endothelial cells of the maternal and fetal microvasculatures. PlGF and its principal receptor Flt-1 were localized to the trophoblasts and fetal vasculature. VEGF-A was found in trophoblast cells and associated with endothelial cells. We detected expression of two Plgf splice variants and four Vegf-a variants. Quantitative real-time polymerase chain reaction analysis showed upregulation of mRNAs encoding pan Vegf-a and all Vegf-a splice forms at gestational days 30-35. Vegf-A showed a marked relative increase in expression during mid-pregnancy, consistent with the pro-angiogenic changes seen in the lamellar zone at days 30-35. Flt-1 was upregulated during late pregnancy. Plgf variants showed stable expression during the first two-thirds of pregnancy, followed by a marked increase toward term. These findings revealed specific spatiotemporal expression patterns of VEGF-A family members consistent with pivotal roles during normal placental development.

Tissue Contamination Challenges the Credibility of Machine Learning Models in Real World Digital Pathology

Machine learning (ML) models are poised to transform surgical pathology practice. The most successful use attention mechanisms to examine whole slides, identify which areas of tissue are diagnostic, and use them to guide diagnosis. Tissue contaminants, such as floaters, represent unexpected tissue. Although human pathologists are extensively trained to consider and detect tissue contaminants, we examined their impact on ML models. We trained 4 whole-slide models. Three operate in placenta for the following functions: (1) detection of decidual arteriopathy, (2) estimation of gestational age, and (3) classification of macroscopic placental lesions. We also developed a model to detect prostate cancer in needle biopsies. We designed experiments wherein patches of contaminant tissue are randomly sampled from known slides and digitally added to patient slides and measured model performance. We measured the proportion of attention given to contaminants and examined the impact of contaminants in the t-distributed stochastic neighbor embedding feature space. Every model showed performance degradation in response to one or more tissue contaminants. Decidual arteriopathy detection--balanced accuracy decreased from 0.74 to 0.69 ± 0.01 with addition of 1 patch of prostate tissue for every 100 patches of placenta (1% contaminant). Bladder, added at 10% contaminant, raised the mean absolute error in estimating gestational age from 1.626 weeks to 2.371 ± 0.003 weeks. Blood, incorporated into placental sections, induced false-negative diagnoses of intervillous thrombi. Addition of bladder to prostate cancer needle biopsies induced false positives, a selection of high-attention patches, representing 0.033 mm2, and resulted in a 97% false-positive rate when added to needle biopsies. Contaminant patches received attention at or above the rate of the average patch of patient tissue. Tissue contaminants induce errors in modern ML models. The high level of attention given to contaminants indicates a failure to encode biological phenomena. Practitioners should move to quantify and ameliorate this problem.

Placental fetal vascular malperfusion, neonatal neurologic morbidity, and infant neurodevelopmental outcomes: a systematic review and meta-analysis

OBJECTIVE

This study aimed to evaluate the association of placental fetal vascular malperfusion lesions with neonatal brain injury and adverse infant neurodevelopmental outcomes.

DATA SOURCES

PubMed and Medline, Scopus, and Cochrane databases were searched from inception to July 2022.

STUDY ELIGIBILITY CRITERIA

We included cohort and case-control studies reporting the associations of fetal vascular malperfusion lesions with neonatal encephalopathy, perinatal stroke, intracranial hemorrhage, periventricular leukomalacia, and infant neurodevelopmental and cognitive outcomes.

METHODS

Data were analyzed by including fetal vascular malperfusion lesions as an exposure variable and brain injuries or neurodevelopmental impairment as outcomes using random-effects models. The effect of moderators, such as gestational age or study type, was assessed by subgroup analysis. Study quality and risk of bias were assessed by applying the Observational Study Quality Evaluation method.

RESULTS

Out of the 1115 identified articles, 26 were selected for quantitative analysis. The rates of neonatal central nervous system injury (neonatal encephalopathy or perinatal stroke) in term or near-term infants were more common among fetal vascular malperfusion cases (n=145) than among controls (n=1623) (odds ratio, 4.00; 95% confidence interval, 2.72-5.90). In premature deliveries, fetal vascular malperfusion lesions did not influence the risk of intracranial hemorrhage or periventricular leukomalacia (odds ratio, 1.40; 95% confidence interval, 0.90-2.18). Fetal vascular malperfusion-associated risk of abnormal infant neurodevelopmental outcome (314 fetal vascular malperfusion cases and 1329 controls) was modulated by gestational age being higher in term infants (odds ratio, 5.02; 95% confidence interval, 1.59-15.91) than in preterm infants (odds ratio, 1.70; 95% confidence interval, 1.13-2.56). Abnormal infant cognitive development and mental development were more common among fetal vascular malperfusion cases (n=241) than among controls (n=2477) (odds ratio, 2.14; 95% confidence interval, 1.40-3.27). The type of study (cohort vs case-control) did not influence the association between fetal vascular malperfusion and subsequent infant brain injury or abnormal neurodevelopmental outcome.

CONCLUSION

The findings of cohort and case-control studies indicate a considerable association between fetal vascular malperfusion placental lesions and increased risk of brain injury in term neonates, and neurodevelopmental impairment in both term and preterm infants. A diagnosis of placental fetal vascular malperfusion should be taken into consideration by both pediatricians and neurologists during the follow-up of infants at risk of adverse neurodevelopmental outcomes.

Placental Histopathologic Findings in the Setting of Prenatally Diagnosed Major Congenital Heart Disease

Objectives: Studies suggest an association between placenta and congenital heart disease (CHD). We evaluated placental pathologies associated with major CHD. Methods: A prospective study included fetuses with major CHD, identified by fetal echocardiography. Fetal Doppler of umbilical artery (UA), middle cerebral artery (MCA), and placental histopathology were assessed. Outcome was measured by mortality at one month of age. Results: 21 cases were analyzed. Hypoplastic left heart syndrome was the commonest lesion (23.8%). Significant differences were detected among categories regarding MCA systolic/diastolic (S/D) ratio & pulsatility index (p = 0.023; 0.036), respectively. Placental histopathologies were demonstrated in 18(85.7%), predominately involved fetal malperfusion lesions 16/21(76.2%), especially chorangiosis (33.3%). No significant association was detected between placental histopathological abnormalities and Doppler parameter, diagnostic category, or mortality. Conclusion: The high prevalence of abnormal placental histopathological findings in major fetal CHD provides additional evidence of placental-cardiac interlinkage. No association was detected between abnormal placental histopathology and fetal Doppler measurements or neonatal outcome of CHD.

The association of placental pathology and neurodevelopmental outcomes in patients with neonatal encephalopathy

BACKGROUND

Studies conflict on how acute versus chronic placental pathology impacts outcomes after neonatal encephalopathy from presumed hypoxic-ischemic encephalopathy (HIE). We examine how outcomes after presumed HIE vary by placental pathology categories.

METHODS

We performed retrospective chart review for neonates with presumed HIE, regardless of severity, focusing on 50 triads for whom placental specimens were available for re-review. Placentas were categorized as having only acute, any chronic, or no lesions. Primary outcomes included in-hospital morbidity/mortality and long-term neurodevelopmental symptoms. Secondary outcomes assessed neonatal MRI and EEG.

RESULTS

Demographics did not differ between groups. Forty-seven neonates were treated with therapeutic hypothermia. Placental acuity category was not associated with primary or secondary outcomes, but clinical and/or histopathological chorioamnionitis was associated with abnormal EEG background and post-neonatal epilepsy (16.7%, n = 3 with chorioamnionitis versus 0%, n = 0 without chorioamnionitis, p = 0.04).

CONCLUSIONS

When grouped by acute, chronic, or absent placental lesions, we observed no association with in-hospital, neurodevelopmental, MRI, or EEG outcomes. When reanalyzed by the presence of chorioamnionitis, we found that chorioamnionitis appeared to be associated with a higher risk of EEG alterations and post-neonatal epilepsy. Despite our limited sample size, our results emphasize the critical role of placental examination for neuroprognostication in presumed HIE.

IMPACT

Neonatal encephalopathy presumed to result from impaired fetal cerebral oxygenation or blood flow is called hypoxic ischemic encephalopathy (HIE). Prior studies link placental pathology to various outcomes after HIE but disagree on the impact of acute versus chronic pathology. Our study determines that neurodevelopmental outcomes, in-hospital outcomes, injury on MRI, and EEG findings in patients with HIE are not differentially associated with acute versus chronic placental pathology. Chorioamnionitis is associated with an increased risk of abnormal EEG patterns and post-neonatal epilepsy. Histopathologic chorioamnionitis without clinical symptoms is common in HIE, emphasizing the crucial role of placental pathology for neuroprognostication.

Placental characteristics and neonatal weights among women with malaria-preeclampsia comorbidity and healthy pregnancies

BACKGROUND

Malaria and preeclampsia are leading causes of maternal morbidity and mortality in sub-Saharan Africa. They contribute significantly to poor perinatal outcomes like low neonatal weight by causing considerable placental morphological changes that impair placental function. Previous studies have described the effects of either condition on the placental structure but the structure of the placenta in malaria-preeclampsia comorbidity is largely understudied despite its high burden. This study aimed to compare the placental characteristics and neonatal weights among women with malaria-preeclampsia comorbidity versus those with healthy pregnancies.

METHODOLOGY

We conducted a retrospective cohort study among 24 women with malaria-preeclampsia comorbidity and 24 women with healthy pregnancies at a County Hospital in Western Kenya. Neonatal weights, gross and histo-morphometric placental characteristics were compared among the two groups.

RESULTS

There was a significant reduction in neonatal weights (P<0.001), placental weights (P = 0.028), cord length (P<0.001), and cord diameter (P<0.001) among women with malaria-preeclampsia comorbidity compared to those with healthy pregnancies. There was also a significant reduction in villous maturity (P = 0.016) and villous volume density (P = 0.012) with increased villous vascularity (P<0.007) among women with malaria-preeclampsia comorbidity compared to those with healthy pregnancies.

CONCLUSION

Placental villous maturity and villous volume density are significantly reduced in patients with malaria-preeclampsia comorbidity with a compensatory increase in villous vascularity. This leads to impaired placental function that contributes to lower neonatal weights.

A follow up investigation of placental pathology, responsive parenting, and preschool children's executive functioning and language development

Despite documented effects linking underlying placental diseases and neurological impairments in children, little is known about the long-term effects of placental pathology on children's neurocognitive outcomes. In addition, maternal responsivity, known to positively influence early postnatal cognitive development, may act to protect children from putative adverse effects of placental pathology. The current study is a follow up of medically healthy, term born, preschool age children, born with placental pathology. A sample of 118 children (45 comparison children with normal placental findings, 73 born with placental pathology) were followed when children were 3-4 years old. In comparison to children born to mothers with normal placentas, placental pathology was associated with poorer performance in the executive function involving cognitive flexibility, but not inhibitory control or receptive language. Maternal responsivity was observed to be marginally protective on the impact of placental pathology risk on cognitive flexibility, but this was not seen for either inhibitory control or receptive language.

Placental pathology in perinatal asphyxia: a case-control study

Introduction

Placentas of term infants with birth asphyxia are reported to have more lesion such as maternal vascular malperfusion (MVM), fetal vascular malperfusion (FVM) and chorioamnionitis with fetal response (FIR) than those of term infants without birth asphyxia. We compared the placental pathology of asphyxiated newborns, including those who developed hypoxic-ischemic encephalopathy (HIE), with non-asphyxiated controls.

Methods

We conducted a retrospective case-control study of placentas from neonates with a gestational age ≥ 35 weeks, a birthweight ≥ 1,800 g, and no malformations. Cases were asphyxiated newborns (defined as those with an umbilical artery pH ≤ 7.0 or base excess ≤ -12 mMol, 10-minute Apgar score ≤ 5, or the need for resuscitation lasting >10 min) from a previous cohort, with (n=32) and without (n=173) diagnosis of HIE. Controls were non-asphyxiated newborns from low-risk l (n= 50) or high-risk (n= 68) pregnancies. Placentas were analyzed according to the Amsterdam Placental Workshop Group Consensus Statement 2014.

Results

Cases had a higher prevalence of nulliparity, BMI>25, thick meconium, abnormal fetal heart monitoring, and acute intrapartum events than controls (p<0.001). MVM and FVM were more frequent among non-asphyxiated than asphyxiated newborns (p<0.001). There was no significant difference in inflammatory lesions or abnormal umbilical insertion site. Histologic meconium-associated changes (MAC) were observed in asphyxiated newborns only (p= 0.039).

Discussion

Our results confirm the role of antepartum and intrapartum risk factors in neonatal asphyxia and HIE. No association between neonatal asphyxia and placental lesions was found, except for in the case of MAC. The association between clinical and placental data is crucial to understanding and possibly preventing perinatal asphyxia in subsequent pregnancies.

Placental Findings in Infants Gestational Age < 34 Weeks and Impact on Short-Term Outcomes

AIM

To analyse placental changes in infants' gestational age < 34 weeks and its correlation to short-term respiratory outcomes or death until hospital discharge.

MATERIAL AND METHODS

Information regarding all in-house born preterm infants born before 34 weeks gestation and born from January 2009 until December 2014 were collected and included among others, placental pathology and relevant data on demographics and outcomes of infants.

RESULTS

Placental abnormalities was found in 157/253 (65.05%) cases. Acute placental inflammation was found to be the most common in both groups of premature neonates, followed by maternal vascular underperfusion. Maternal vascular underperfusion was significantly more common in GA ≤ 27 weeks compared to infants GA 28-33 weeks (35.2% vs. 13.7%; p = 0.018). Similarly, chronic placental inflammation was more common in infants GA ≤ 27 weeks compared to infants GA 28-33 weeks (14.3% vs. 3.3%; p = 0.014). Infants with placental pathology had a lower median birth weight (1460g vs. 1754g; p = 0.001, and were of shorter median GA at birth (31 vs. 32; p = 0.001). Infants with any placental disease had higher rates of death until hospital discharge (10.2% vs. 3.1%; p = 0.039) and higher rates of any stage of bronchopulmonary dysplasia (41.4% vs. 26.0%; p = 0.013). There were no significant differences in mechanical ventilation rates, duration of mechanical ventilation and duration of supplemental oxygen therapy.

CONCLUSION

Identifiable placental abnormalities were found in most infants born < 34 weeks gestation. Placental pathology is associated with increased rates of bronchopulmonary dysplasia and death until hospital discharge.

Tissue contamination challenges the credibility of machine learning models in real world digital pathology

Machine learning (ML) models are poised to transform surgical pathology practice. The most successful use attention mechanisms to examine whole slides, identify which areas of tissue are diagnostic, and use them to guide diagnosis. Tissue contaminants, such as floaters, represent unexpected tissue. While human pathologists are extensively trained to consider and detect tissue contaminants, we examined their impact on ML models. We trained 4 whole slide models. Three operate in placenta for 1) detection of decidual arteriopathy (DA), 2) estimation of gestational age (GA), and 3) classification of macroscopic placental lesions. We also developed a model to detect prostate cancer in needle biopsies. We designed experiments wherein patches of contaminant tissue are randomly sampled from known slides and digitally added to patient slides and measured model performance. We measured the proportion of attention given to contaminants and examined the impact of contaminants in T-distributed Stochastic Neighbor Embedding (tSNE) feature space. Every model showed performance degradation in response to one or more tissue contaminants. DA detection balanced accuracy decreased from 0.74 to 0.69 +/- 0.01 with addition of 1 patch of prostate tissue for every 100 patches of placenta (1% contaminant). Bladder, added at 10% contaminant raised the mean absolute error in estimating gestation age from 1.626 weeks to 2.371 +/ 0.003 weeks. Blood, incorporated into placental sections, induced false negative diagnoses of intervillous thrombi. Addition of bladder to prostate cancer needle biopsies induced false positives, a selection of high-attention patches, representing 0.033mm2, resulted in a 97% false positive rate when added to needle biopsies. Contaminant patches received attention at or above the rate of the average patch of patient tissue. Tissue contaminants induce errors in modern ML models. The high level of attention given to contaminants indicates a failure to encode biological phenomena. Practitioners should move to quantify and ameliorate this problem.

Placental histopathology, maternal characteristics and neonatal outcome in cases of preterm birth in a high-risk population in South Africa

Background. Preterm birth remains a global health concern and is one of the most common pregnancy complications associated with perinatal morbidity and mortality.Objective. To investigate placental pathology and its associations with obstetric, maternal and neonatal outcomes in the Eastern Cape region of South Africa (SA) in order to help understand its associations with preterm birth in that region. Methods. In this prospective study, placentas were collected consecutively from patients attending a public tertiary referral hospital in SA, delivering preterm (n=100; 28 - 34 weeks gestational age) and term (n=20; >36 weeks gestational age). Placentas were submitted for histopathology, and comparisons with maternal characteristics and neonatal outcomes in preterm birth were undertaken.Results. Histological analysis revealed pathology in all preterm placentas (100%), with maternal vascular malperfusion (47%) and abruptio placentae (41%) most commonly identified. Acute chorioamnionitis (21%) was associated with term births (p=0.002). Maternal characteristics and neonatal outcomes significantly associated with preterm birth included pre-eclampsia (p=0.006), neonatal respiratory distress syndrome (p=0.004) and neonatal jaundice (p=0.003). Intrauterine demise (p=0.004) and alcohol abuse (p≤0.005) were significantly associated with term delivery. The number of mothers delivering preterm who were HIV-positive was high (41%). Conclusion. The pathology identified in all preterm placentas supports the need to update institutional policies for submission of placentas from all preterm births for histopathology, particularly in countries with a high burden of preterm birth.

Machine learning classification of placental villous infarction, perivillous fibrin deposition, and intervillous thrombus

INTRODUCTION

Placental parenchymal lesions are commonly encountered and carry significant clinical associations. However, they are frequently missed or misclassified by general practice pathologists. Interpretation of pathology slides has emerged as one of the most successful applications of machine learning (ML) in medicine with applications ranging from cancer detection and prognostication to transplant medicine. The goal of this study was to use a whole-slide learning model to identify and classify placental parenchymal lesions including villous infarctions, intervillous thrombi (IVT), and perivillous fibrin deposition (PVFD).

METHODS

We generated whole slide images from placental discs examined at our institution with infarct, IVT, PVFD, or no macroscopic lesion. Slides were analyzed as a set of overlapping patches. We extracted feature vectors from each patch using a pretrained convolutional neural network (EfficientNetV2L). We trained a model to assign attention to each vector and used the attentions as weights to produce a pooled feature vector. The pooled vector was classified as normal or 1 of 3 lesions using a fully connected network. Patch attention was plotted to highlight informative areas of the slide.

RESULTS

Overall balanced accuracy in a test set of held-out slides was 0.86 with receiver-operator characteristic areas under the curve of 0.917-0.993. Cases of PVFD were frequently miscalled as normal or infarcts, the latter possibly due to the perivillous fibrin found at the periphery of infarctions. We used attention maps to further understand some errors, including one most likely due to poor tissue fixation and processing.

DISCUSSION

We used a whole-slide learning paradigm to train models to recognize three of the most common placental parenchymal lesions. We used attention maps to gain insight into model function, which differed from intuitive explanations.

Placental Changes and Neuropsychological Development in Children-A Systematic Review

Placental dysfunction may increase the offspring's later-life disease risk. The objective of this systematic review was to describe associations between pathological placental changes and neuropsychological outcomes in children after the neonatal period. The inclusion criteria were human studies; original research; direct placental variables; neuropsychological outcomes; and analysis between their associations. The exclusion criterion was the offspring's age-0-28 days or >19 years. The MEDLINE and EMBASE databases were last searched in May 2022. We utilized the ROBINS-I for the risk of bias assessment and performed a narrative synthesis. In total, 3252 studies were identified, out of which 16 were included (i.e., a total of 15,862 participants). Half of the studies were performed on children with neonatal complications, and 75% of the studies reported an association between a placental change and an outcome; however, following the completion of the funnel plots, a risk of publication bias was indicated. The largest study described a small association between placental size and a risk of psychiatric symptoms in boys only. Inconsistency between the studies limited the evidence in this review. In general, no strong evidence was found for an association between pathological placental changes and childhood neuropsychological outcomes after the neonatal period. However, the association between placental size and mental health in boys indicates a placental sexual dimorphism, thereby suggesting an increased vulnerability for male fetuses.

Placental pathology as a marker of brain injury in infants with hypoxic ischemic encephalopathy

BACKGROUND

Hypoxic Ischemic Encephalopathy (HIE) can lead to devastating consequences for the affected infant. Although therapeutic cooling benefits infants with moderate and severe HIE, differentiating mild from moderate-severe HIE may be challenging. The placenta reflects the fetal intrauterine environment and may reveal underlying processes that affect brain injury.

AIM

To describe placental histopathology using the Amsterdam Placental Workshop Group Criteria in different grades of HIE.

STUDY DESIGN

Retrospective cohort.

SUBJECTS

Infants admitted to a tertiary care neonatal intensive care unit with a diagnosis of HIE between 2011 and 2016.

OUTCOME MEASURE

Maternal and neonatal clinical variables and placental histopathology using the Amsterdam Placental Workshop Group Criteria were compared between mild and moderate-severe HIE. Mann-Whitney or t-test or ꭓ² were performed for bivariate associations as appropriate. To explain the relationship between placental pathology and severity of HIE odds ratios (ORs) and 95 % confidence intervals (CIs) were calculated using logistic regression models.

RESULTS

Of the 73 infants in the study, 23 had mild and 50 moderate-sever HIE. There was no difference in maternal and neonatal characteristics except for sentinel events which were higher in the moderate- severe group. On placental histopathology, acute inflammation, including fetal inflammatory reaction (FIR) were significantly higher in the moderate-severe group. After adjusting for confounders, FIR remained significantly associated with moderate-severe HIE, ORs 6.29, 95 % CI 1.5-25.

CONCLUSION

Our study demonstrates FIR in the placenta is associated with severity of HIE.

Patterns in Prenatal Physical Activity and Sedentary Behavior: Associations With Blood Pressure and Placental Features in the MoMHealth Cohort

BACKGROUND

Moderate to vigorous physical activity (MVPA) and sedentary behavior (SED) are associated with blood pressure (BP) and adverse pregnancy outcomes. The authors investigated associations of prenatal MVPA and SED patterns with BP and with placental malperfusion features.

METHODS

Women enrolled in this prospective cohort study in the first trimester. MVPA, SED, and BP were measured objectively each trimester. MVPA and SED trajectories were constructed. Placental examinations were conducted in a subset. Associations of trajectories with BPs were assessed with linear regression adjusted for age, race, education, prepregnancy body mass index, and gestational age. Associations with placental malperfusion lesions and weight were adjusted for key covariates.

RESULTS

One hundred eleven participants were included; placental exams were available in 50. Participants with high (vs low) SED were younger and more likely to have adverse pregnancy outcomes. High SED (vs low) was associated with higher first trimester systolic (β = 5.3; 95% confidence interval, 0.0 to 10.6) and diastolic (β = 5.0; 95% confidence interval, 1.4 to 8.6) and higher second trimester diastolic (β = 4.9; 95% confidence interval, 1.6 to 8.2) BP. Medium and high MVPA groups were associated with lower postpartum diastolic BP. Trajectories were not associated with placental malperfusion.

CONCLUSIONS

MVPA and SED patterns were differentially associated with prenatal and postpartum BP. Encouraging favorable levels of both might help women achieve lower BP during and after pregnancy.

Practice variations for fetal and neonatal congenital heart disease within the Children's Hospitals Neonatal Consortium

BACKGROUND

Many aspects of care for fetuses and neonates with congenital heart disease (CHD) fall outside standard practice guidelines, leading to the potential for significant variation in clinical care for this vulnerable population.

METHODS

We conducted a cross-sectional survey of site sponsors of the Children's Hospitals Neonatal Consortium, a multicenter collaborative of 41 Level IV neonatal intensive care units to assess key areas of clinical practice variability for patients with fetal and neonatal CHD.

RESULTS

We received responses from 31 centers. Fetal consult services are shared by neonatology and pediatric cardiology at 70% of centers. Three centers (10%) routinely perform fetal magnetic resonance imaging (MRI) for women with pregnancies complicated by fetal CHD. Genetic testing for CHD patients is routine at 76% of centers. Preoperative brain MRI is standard practice at 5 centers (17%), while cerebral NIRS monitoring is regularly used at 14 centers (48%). Use of electroencephalogram (EEG) after major cardiac surgery is routine in 5 centers (17%). Neurodevelopmental follow-up programs are offered at 30 centers (97%).

CONCLUSIONS

Many aspects of fetal and neonatal CHD care are highly variable with evolving shared multidisciplinary models.

IMPACT

Many aspects of fetal and neonatal CHD care are highly variable. Genetic testing, placental examination, preoperative neuroimaging, and postoperative EEG monitoring carry a high yield of finding abnormalities in patients with CHD and these tests may contribute to more precise prognostication and improve care. Evidence-based standards for prenatal and postnatal CHD care may decrease inter-center variability.

Gestational exposure to NO2 aggravates placental senescence

Placental senescence is a normal physiological process of placenta, while premature placental senescence has been confirmed to be associated with some adverse pregnancy complications. Epidemiological studies indicate that NO₂ exposure can aggravate placental senescence which is represented by fibrosis and abnormal telomere homeostasis, etc. In this study, pregnant C57BL/6 mice were exposed to NO₂ (2.5 ppm, 5 h/day) daily in a dynamic exposure chamber throughout the gestation period, and were sacrificed at embryonic day 13.5 (E13.5), E15.5 and E18.5. Placenta were harvested and conducted for histopathological examination and telomere evaluation. Our results showed that gestational NO₂ exposure significantly aggravated placental fibrosis and calcification, and up-regulated the related bio-markers (connective tissue growth factor (Ctgf) and transforming growth factor-β1 (Tgf-β1)) at E18.5. In addition, gestational exposure to NO₂ also activated senescence related pathway (p53/p21) at E18.5. Furthermore, gestational NO₂ exposure significantly shortened telomere length at E18.5, and the expression of telomere homeostasis regulation genes telomeric repeat binding factor 1 (Trf1), protection of telomeres 1a (Pot1a) and Pot1b were significantly increased while telomerase reverse transcriptase (Tert) was suppressed after NO₂ exposure at E13.5 or E18.5, respectively. Importantly, DNA methylation status of the 22^nd at E13.5 and 32^nd at E18.5 site in sub-telomeric region of chromosome 1 was significantly altered. Based on the above results, our present study indicated that gestational NO₂ exposure could lead to premature placental senescence during the late trimester of pregnancy via aggravation of fibrosis and telomere length shortening regulated by telomere regulatory enzyme and DNA methylation.

Post-mortem magnetic resonance imaging with computed tomography-guided biopsy for foetuses and infants: a prospective, multicentre, cross-sectional study

Background

Post-mortem imaging has been suggested as an alternative to conventional autopsy in the prenatal and postnatal periods. Noninvasive autopsies do not provide tissue for histological examination, which may limit their clinical value, especially when infection-related morbidity and mortality are suspected.

Methods

We performed a prospective, multicentre, cross-sectional study to compare the diagnostic performance of post-mortem magnetic resonance imaging with computed tomography-guided biopsy (Virtopsy®) with that of conventional autopsy in foetuses and infants. Cases referred for conventional autopsy were eligible for enrolment. After post-mortem imaging using a computed tomography scanner and a magnetic resonance imaging unit, computed tomography-guided tissue sampling was performed. Virtopsy results were compared with conventional autopsy in determining the likely final cause of death and major pathologies. The primary outcome was the proportion of cases for which the same cause of death was determined by both methods. Secondary outcomes included the proportion of false positive and false negative major pathological lesions detected by virtopsy and the proportion of computed tomography-guided biopsies that were adequate for histological examination.

Results

Overall, 101 cases (84 fetuses, 17 infants) were included. Virtopsy and autopsy identified the same cause of death in 91 cases (90.1%, 95% CI 82.7 to 94.5). The sensitivity and specificity of virtopsy for determining the cause of death were 96.6% (95% CI 90.6 to 98.8) and 41.7% (95% CI 19.3 to 68.0), respectively. In 32 cases (31.7%, 95% CI 23.4 to 41.3), major pathological findings remained undetected by virtopsy, and in 45 cases (44.6%, 95% CI 35.2 to 54.3), abnormalities were diagnosed by virtopsy but not confirmed by autopsy. Computed tomography-guided tissue sampling was adequate for pathological comments in 506 of 956 biopsies (52.7%) and added important diagnostic value in five of 30 cases (16.1%) with an unclear cause of death before autopsy compared with postmortem imaging alone. In 19 of 20 infective deaths (95%), biopsies revealed infection-related tissue changes. Infection was confirmed by placental examination in all fetal cases.

Conclusions

Virtopsy demonstrated a high concordance with conventional autopsy for the detection of cause of death but was less accurate for the evaluation of major pathologies. Computed tomography-guided biopsy had limited additional diagnostic value.

Trial registration

ClinicalTrials.gov (NCT01888380).

Supplementary Information

The online version contains supplementary material available at 10.1186/s12887-022-03519-4.

Placental histology following assisted hatching in fresh transfer cycles

PURPOSE

To assess placental histological findings following assisted hatching in fresh transfer in vitro fertilization cycles.

METHODS

Evaluation of a historic cohort of live singleton deliveries after fresh embryo transfer (ET) at a single university medical center between 2009 and 2017. We compared perinatal outcomes and placental histology in cases where assisted hatching was performed prior to ET (AH group) and cases with no AH (no AH group).

RESULTS

Overall, 166 deliveries following AH were compared to 494 deliveries with no AH. Patients' demographics were similar between the groups. Median antral follicle count was significantly lower in the AH group, median 11 (range 1-50) vs. 16 (range 1-80), p < 0.001, and the primary indication for infertility treatment significantly more often diminished ovarian reserve (p < 0.001). Cycle characteristics in the AH group included a higher gonadotropin dose employed, and a lower rate of single and blastocyte transfer. Pregnancies following AH were associated with less low-lying placentas, 0.6% vs. 6.2%, p = 0.001, and comparable for other perinatal outcomes. After adjusting for confounders, the rate of bilobated placentas was higher following AH, aOR 7.10, 95% CI 1.50-33.51. The rate of perivillous depositions was higher with AH, aOR, 95% CI 3.18, 1.46-6.93, and the rate of chorangiosis lower in this group, aOR, 95% CI 0.32, 0.11-0.93. The overall rate of vascular lesions was similar between the groups.

CONCLUSION

Pregnancies following AH are notable for a lower rate of placenta previa, yet a higher rate of bilobated placentas and perivillous depositions and less chorangiosis, warranting further investigation.

Placental dysfunction influences fetal monocyte subpopulation gene expression in preterm birth

The placenta is the primary organ for immune regulation, nutrient delivery, gas exchange, protection against environmental toxins, and physiologic perturbations during pregnancy. Placental inflammation and vascular dysfunction during pregnancy are associated with a growing list of prematurity-related complications. The goal of this study was to identify differences in gene expression profiles in fetal monocytes - cells that persist and differentiate postnatally - according to distinct placental histologic domains. Here, by using bulk RNA-Seq, we report that placental lesions are associated with gene expression changes in fetal monocyte subsets. Specifically, we found that fetal monocytes exposed to acute placental inflammation upregulate biological processes related to monocyte activation, monocyte chemotaxis, and platelet function, while monocytes exposed to maternal vascular malperfusion lesions downregulate these processes. Additionally, we show that intermediate monocytes might be a source of mitogens, such as HBEGF, NRG1, and VEGFA, implicated in different outcomes related to prematurity. This is the first study to our knowledge to show that placental lesions are associated with unique changes in fetal monocytes and monocyte subsets. As fetal monocytes persist and differentiate into various phagocytic cells following birth, our study may provide insight into morbidity related to prematurity and ultimately potential therapeutic targets.

Placental Heterogeneity in Stillbirth and Its Relations to Maternal Exogenous Characteristics

INTRODUCTION

Heterogeneous patterns of placental lesions in stillbirth signal important variations in placental histopathology that may be diagnostic in stillbirth. We explore placental heterogeneity and its associations with maternal characteristics (including HIV) using latent class analysis.

METHODS

Placental and maternal data and slides were assessed retrospectively for 122 confirmed stillbirths (gestational age ≥ 28 weeks) delivered at a major South African academic hospital between January 2016-July 2018. The slides were reviewed by 2 pathologists and classified using the Amsterdam Consensus Classification System. Latent class analyses were conducted on raw data.

RESULTS

We identify 5 latent placental classes in stillbirth based on similarity in patterns of observed diagnostic criteria and their associations with maternal characteristics. Three classes bear similarity to generalized patterns of placental injury identified previously. Our study shows that intrauterine infection was the commonest histopathological condition associated with stillbirth in our setting. Novel findings include 2 classes, distinguished by high placental RPH and maternal HIV, respectively, and the non-emergence of a class distinguished by VUE.

CONCLUSION

The size and content of the latent classes and their similarity/dissimilarity to the more generalized patterns identified previously suggest potential new avenues for investigation and theory development concerning the role of the placenta in stillbirth and the impact of HIV.

First-trimester biomarkers and the risk of cerebral palsy

BACKGROUND

Cerebral palsy (CP) is the most common severe motor disability and a manifestation of early brain damage.

AIMS

To analyze if abnormal levels of first-trimester biomarkers were associated with CP. Furthermore, to investigate their clinical applicability in early predicting of CP.

STUDY DESIGN

Nationwide cohort study.

SUBJECTS

We included 258.057 singleton live births, born during 2008-2013 with completed first-trimester assessments.

OUTCOME MEASURES

Data on beta subunit of human chorionic gonadotropin (beta-hCG), pregnancy-associated plasma protein-A (PAPP-A), nuchal translucency thickness, and biparietal diameter (BPD) were converted to multiple of the medians (MoM). Associations were analyzed by comparing mean and extreme levels between pregnancies with and without CP. All CP diagnoses were validated by trained neuropediatricians. Logistic regression was used to create an early prediction model.

RESULTS

The mean beta-hCG value was significantly lower in pregnancies with CP (0.96MoM [95% CI 0.91-1.02] vs 1.04MoM [1.04-1.04], p = 0.01) and the mean PAPP-A value tended to be lower (0.96MoM [0.91-1.01] vs 1.01MoM [1.00-1.01], p = 0.07). Moreover, fetuses that developed CP more likely had a BPD measurement below the fifth percentile (7.5% vs 5%, p = 0.045). The final prediction model had poor discrimination.

CONCLUSIONS

Pregnancies with CP tend to have lower values of beta-hCG and PAPP-A in the first trimester, however, the associations are mediated differently. Nonetheless, abnormal levels of the most common first-trimester biomarkers only have weak associations with CP; resulting in inadequate predictive abilities when included in an early prediction model.

Placental histology and pregnancy complications following intracytoplasmic sperm injection for non-male factor infertility

PURPOSE

To assess obstetric outcomes and placental histology following intracytoplasmic sperm injection (ICSI), for non-male infertility.

METHODS

This was a retrospective cohort of live born singleton deliveries after in vitro fertilization (IVF) at a single university affiliated medical center between 2009 and 2017. Excluded were IVF cycles with male infertility and oocyte recipients. We compared obstetric outcomes and placental histology in cases ICSI was performed (ICSI group) and cases with no ICSI (IVF group).

RESULTS

A total of 400 deliveries following ICSI were compared to 218 in the IVF group. Maternal age was similar between the groups, while diminished ovarian reserve was more common among ICSI patients and tubal disease less common (p < 0.001). The rate of blastocyte transfer was also significantly lower in the ICSI group-67.5% vs. 77%, p = 0.01. Pregnancies following ICSI were characterized by similar rates of preeclampsia, preterm birth, and small for gestational age neonates. Although cesarean delivery rate was significantly higher in the group, this did no attain significance after adjustment for confounders. Placentas in the ICSI group were notable for a lower rate of villitis of unknown etiology (1% vs. 4.5%, p = 0.007) and a higher rate of maternal surface calcifications (33% vs. 23.8%, p = 0.01) after adjustment for confounders.

CONCLUSION

The employment of ICSI with no male indication is associated with similar obstetric outcomes. Despite isolated placental differences among many investigated, placental histology seems overall comparable as well. These results are reassuring to clinicians and patients.

Clinical correlates of placental pathologic features in early-onset fetal growth restriction

Introdcution: The purpose of this study was to evaluate the association between placental pathologic features of maternal (MVM) or fetal (FVM) vascular malperfusion and clinical characteristics, sonographic findings and neonatal outcome in a cohort of pregnancies complicated by early-onset (diagnosed before 32 weeks of gestational age) fetal growth restriction (FGR).

METHODS

A prospective cohort study included 250 singleton early-onset FGR pregnancies diagnosed, followed up and delivered at a single Centre. Elementary placental pathologic lesions were classified according to standard recommendations. Logistic regression and Cox analysis were used to evaluate outcomes adjusting for confounders.

RESULTS

Overall features of severe placental MVM and FVM were observed in 29.6% (74/250) and 12.8% (32/250) of the subjects, respectively. Severe placental MVM lesions were more common among subjects with umbilical artery (UA) Doppler Pulsatility Index > 95th than ≤ 95th percentile (50/120 as opposed to 24/130, Adj OR= 3, 95% CI = 1.6-5.4) and CerebroPlacental Ratio (CPR) < 5th than ≥5th percentile (48/115 as opposed to 26/135, Adj OR= 2.7, 95% CI = 1.5-4.9). Mean time from FGR diagnosis to delivery was shorter among subjects with severe MVM (25.5 days, 95% CI= 20.6-30.2, Adj. OR = 1.9,95% CI = 1.9,95% CI =1.4-2.5) when compared to both those with mild/moderate MVM (36.5 days (95% CI = 27-.2-45, p=0.04) or no MVM (39.4,95% CI = 35.4-43.4, p<.001). Finally, severe FVM was associated with an increased risk of perinatal/neonatal death or severe brain lesions (9/28 in subjects with perinatal/neonatal death/brain lesions as compared to 23/222 in controls, Adj OR= 3, 95% CI = 1.05-8.6) or severe adverse neonatal outcomes (13/46 in subjects with severe adverse outcome as compared to 19/204 among controls, Adj OR= 3.2, 95% CI =1.2-8.5).

CONCLUSIONS

In early-onset FGR, placental pathologic features of MVM and FVM are distinct independent predictors of severity of clinical picture, abnormal Doppler markers of placental and fetal circulation and of neonatal outcome, respectively.

Placental Tissue Destruction and Insufficiency from COVID-19 Causes Stillbirth and Neonatal Death from Hypoxic-Ischemic Injury: A Study of 68 Cases with SARS-CoV-2 Placentitis from 12 Countries

CONTEXT.—

Perinatal death is an increasingly important problem as the COVID-19 pandemic continues, but the mechanism of death has been unclear.

OBJECTIVE.—

To evaluate the role of the placenta in causing stillbirth and neonatal death following maternal infection with COVID-19 and confirmed placental positivity for SARS-CoV-2.

DESIGN.—

Case-based retrospective clinico-pathological analysis by a multinational group of 44 perinatal specialists from 12 countries of placental and autopsy pathology findings from 64 stillborns and 4 neonatal deaths having placentas testing positive for SARS-CoV-2 following delivery to mothers with COVID-19.

RESULTS.—

All 68 placentas had increased fibrin deposition and villous trophoblast necrosis and 66 had chronic histiocytic intervillositis, the three findings constituting SARS-CoV-2 placentitis. Sixty-three placentas had massive perivillous fibrin deposition. Severe destructive placental disease from SARS-CoV-2 placentitis averaged 77.7% tissue involvement. Other findings included multiple intervillous thrombi (37%; 25/68) and chronic villitis (32%; 22/68). The majority (19, 63%) of the 30 autopsies revealed no significant fetal abnormalities except for intrauterine hypoxia and asphyxia. Among all 68 cases, SARS-CoV-2 was detected from a body specimen in 16 of 28 cases tested, most frequently from nasopharyngeal swabs. Four autopsied stillborns had SARS-CoV-2 identified in internal organs.

CONCLUSIONS.—

The pathology abnormalities composing SARS-CoV-2 placentitis cause widespread and severe placental destruction resulting in placental malperfusion and insufficiency. In these cases, intrauterine and perinatal death likely results directly from placental insufficiency and fetal hypoxic-ischemic injury. There was no evidence that SARS-CoV-2 involvement of the fetus had a role in causing these deaths.

What is known about neuroplacentology in fetal growth restriction and in preterm infants: A narrative review of literature

The placenta plays a fundamental role during pregnancy for fetal growth and development. A suboptimal placental function may result in severe consequences during the infant's first years of life. In recent years, a new field known as neuroplacentology has emerged and it focuses on the role of the placenta in fetal and neonatal brain development. Because of the limited data, our aim was to provide a narrative review of the most recent knowledge about the relation between placental lesions and fetal and newborn neurological development. Papers published online from 2000 until February 2022 were taken into consideration and particular attention was given to articles in which placental lesions were related to neonatal morbidity and short-term and long-term neurological outcome. Most research regarding the role of placental lesions in neurodevelopment has been conducted on fetal growth restriction and preterm infants. Principal neurological outcomes investigated were periventricular leukomalacia, intraventricular hemorrhages, neonatal encephalopathy and autism spectrum disorder. No consequences in motor development were found. All the considered studies agree about the crucial role played by placenta in fetal and neonatal neurological development and outcome. However, the causal mechanisms remain largely unknown. Knowledge on the pathophysiological mechanisms and on placenta-related risks for neurological problems may provide clues for early interventions aiming to improve neurological outcomes, especially among pediatricians and child psychiatrists.

Autism-Associated DNA Methylation at Birth From Multiple Tissues Is Enriched for Autism Genes in the Early Autism Risk Longitudinal Investigation

Background: Pregnancy measures of DNA methylation, an epigenetic mark, may be associated with autism spectrum disorder (ASD) development in children. Few ASD studies have considered prospective designs with DNA methylation measured in multiple tissues and tested overlap with ASD genetic risk loci. Objectives: To estimate associations between DNA methylation in maternal blood, cord blood, and placenta and later diagnosis of ASD, and to evaluate enrichment of ASD-associated DNA methylation for known ASD-associated genes. Methods: In the Early Autism Risk Longitudinal Investigation (EARLI), an ASD-enriched risk birth cohort, genome-scale maternal blood (early n = 140 and late n = 75 pregnancy), infant cord blood (n = 133), and placenta (maternal n = 106 and fetal n = 107 compartments) DNA methylation was assessed on the Illumina 450k HumanMethylation array and compared to ASD diagnosis at 36 months of age. Differences in site-specific and global methylation were tested with ASD, as well as enrichment of single site associations for ASD risk genes (n = 881) from the Simons Foundation Autism Research Initiative (SFARI) database. Results: No individual DNA methylation site was associated with ASD at genome-wide significance, however, individual DNA methylation sites nominally associated with ASD (P < 0.05) in each tissue were highly enriched for SFARI genes (cord blood P = 7.9 × 10^-29, maternal blood early pregnancy P = 6.1 × 10^-27, maternal blood late pregnancy P = 2.8 × 10^-16, maternal placenta P = 5.6 × 10^-15, fetal placenta P = 1.3 × 10^-20). DNA methylation sites nominally associated with ASD across all five tissues overlapped at 144 (29.5%) SFARI genes. Conclusion: DNA methylation sites nominally associated with later ASD diagnosis in multiple tissues were enriched for ASD risk genes. Our multi-tissue study demonstrates the utility of examining DNA methylation prior to ASD diagnosis.

Impact of Co-Existing Placental Pathologies in Pregnancies Complicated by Placental Abruption and Acute Neonatal Outcomes

Placental abruption (PA) is a concern for maternal and neonatal morbidity. Adverse neonatal outcomes in the setting of PA include higher risk of prematurity. Placental pathologies include maternal vascular malperfusion (MVM), fetal vascular malperfusion (FVM), acute chorioamnionitis, and villitis of unknown etiology (VUE). We aimed to investigate how placental pathology contributes to acute neonatal outcome in PA. A retrospective cohort study of all placentas with PA were identified. Exposures were MVM, FVM, acute chorioamnionitis and VUE. The primary outcome was NICU admission and the secondary outcomes included adverse base deficit and Apgar scores, need for resuscitation, and small-for-gestational age. A total of 287 placentas were identified. There were 160 (59.9%) of placentas with PA alone vs 107 (40.1%) with PA and additional placental pathologies. Odds of NICU admission were more than two times higher in pregnancies with placental pathologies (OR = 2.37, 95% CI 1.28-4.52). These estimates were in large part mediated by prematurity and birthweight, indirect effect acting through prematurity was OR 1.79 (95% CI 1.12-2.75) and through birthweight OR 2.12 (95% CI 1.40-3.18). Odds of Apgar score ≤ 5 was more than four times higher among pregnancies with placental pathologies (OR = 4.56, 95% CI 1.28-21.26). Coexisting placental pathology may impact Apgar scores in pregnancies complicated by PA. This knowledge could be used by neonatal teams to mobilize resources in anticipation of the need for neonatal resuscitation.

The role of confounding in the association between pregnancy complications and subsequent preterm birth: a cohort study

OBJECTIVE

To estimate the degree of confounding necessary to explain the associations between complications in a first pregnancy and the subsequent risk of preterm birth.

DESIGN

Population-based cohort study.

SETTING

Western Australia.

POPULATION

Women (n = 125 473) who gave birth to their first and second singleton children between 1998 and 2015.

MAIN OUTCOME MEASURES

Relative risk (RR) of a subsequent preterm birth (<37 weeks of gestation) with complications of pre-eclampsia, placental abruption, small-for-gestational age and perinatal death (stillbirth and neonatal death within 28 days of birth). We derived e-values to determine the minimum strength of association for an unmeasured confounding factor to explain away an observed association.

RESULTS

Complications in a first pregnancy were associated with an increased risk of a subsequent preterm birth. Relative risks were significantly higher when the complication was recurrent, with the exception of first-term perinatal death. The association with subsequent preterm birth was strongest when pre-eclampsia was recurrent. The risk of subsequent preterm birth with pre-eclampsia was 11.87 (95% CI 9.52-14.79) times higher after a first term birth with pre-eclampsia, and 64.04 (95% CI 53.58-76.55) times higher after a preterm first birth with pre-eclampsia, than an uncomplicated term birth. The e-values were 23.22 and 127.58, respectively.

CONCLUSIONS

The strong associations between recurrent pre-eclampsia, placental abruption and small-for-gestational age with preterm birth supports the hypothesis of shared underlying causes that persist from pregnancy to pregnancy. High e-values suggest that recurrent confounding is unlikely, as any such unmeasured confounding factor would have to be uncharacteristically large.

TWEETABLE ABSTRACT

First pregnancy complications are associated with a higher risk of subsequent preterm birth, with evidence strongest for pregnancies complicated by pre-eclampsia.

Neurologic Sequelae Associated with Hypertensive Disorders of Pregnancy

Hypertensive disorders of pregnancy (HDP) contribute to adverse gene-environment interactions prior to conception and continue throughout pregnancy. Embryonic/fetal brain disorders occur from interactions between genetic susceptibilities interacting with acquired diseases or conditions affecting the maternal/placental fetal (MPF) triad. Trimester-specific pathophysiological mechanisms, such as maternal immune activation and ischemic placental syndrome, contribute to adverse peripartum, neonatal and childhood outcomes. Two diagnostic approaches provide timelier diagnoses over the first 1000 days from conception until two years of age. Horizontal analyses assess the maturation of the triad, neonate and child. Vertical analyses consider systems-biology from genetic, molecular, cellular, tissue through organ networks during each developmental niche. Disease expressions associated with HDP have cumulative adverse effects across the lifespan when subjected to subsequent adverse events. Critical/sensitive periods of developmental neuroplasticity over the first 1000 days are more likely to result in permanent sequelae. Novel diagnostic approaches, beginning during pre-conception, will facilitate the development of effective preventive, rescue and reparative neurotherapeutic strategies in response to HDP-related trimester-specific disease pathways. Public health policies require the inclusion of women's health advocacy during and beyond their reproductive years to reduce sequelae experienced by mothers and their offspring. A lower global burden of neurologic disease from HDP will benefit future generations.

Automated Quantitative Image Evaluation of Antigen Retrieval Methods for 17 Antibodies in Placentation and Implantation Diagnostic and Research

Immunostaining in clinical routine and research highly depends on standardized staining methods and quantitative image analyses. We qualitatively and quantitatively compared antigen retrieval methods (no pretreatment, pretreatment with pepsin, and heat-induced pretreatment with pH 6 or pH 9) for 17 antibodies relevant for placenta and implantation diagnostics and research. Using our newly established, comprehensive automated quantitative image analysis approach, fluorescent signal intensities were evaluated. Automated quantitative image analysis found that 9 out of 17 antibodies needed antigen retrieval to show positive staining. Heat induction proved to be the most efficient form of antigen retrieval. Eight markers stained positive after pepsin digestion, with β-hCG and vWF showing enhanced staining intensities. To avoid the misinterpretation of quantitative image data, the qualitative aspect should always be considered. Results from native placental tissue were compared with sections of a placental invasion model based on thermo-sensitive scaffolds. Immunostaining on placentas in vitro leads to new insights into fetal development and maternal pathophysiological pathways, as pregnant women are justifiably excluded from clinical studies. Thus, there is a clear need for the assessment of reliable immunofluorescent staining and pretreatment methods. Our evaluation offers a powerful tool for antibody and pretreatment selection in placental research providing objective and precise results.

Placental Pathologic Changes Associated with Fetal Growth Restriction and Consequent Neonatal Outcomes

To evaluate the pathological changes of the placenta to determine the mechanism underlying placenta-derived fetal growth restriction (FGR) and investigate its influence on neonatal outcomes. Study design: This retrospective case-control study included 120 singleton pregnancies with FGR as well as 120 gestational age-matched controls. We compared the placental pathological findings and neonatal outcomes according to the presence of placental malperfusion. Results: The FGR group demonstrated lower placental weight (350.8 ± 118.8 vs. 436.1 ± 109.7g, P < .0001), smaller chorionic plate area (157.7 ± 48.0 vs. 201.5 ± 53.4 cm², P < .0001), and higher rate of villous change lesions (84.2% vs. 52.5%, P < .0001) than the control group. FGR neonates with placental malperfusion had a higher rate of adverse neonatal outcomes (87.1% vs. 63.2%, P = .0175). Conclusion: Small placentas and placental malperfusion reflected in villous changes are associated with FGR. FGR neonates with placental malperfusion are more susceptible to adverse neonatal outcomes.

Placental features of fetal vascular malperfusion and infant neurodevelopmental outcomes at 2 years of age in severe fetal growth restriction

BACKGROUND

Placental pathologic lesions suggesting maternal or fetal vascular malperfusion are common among pregnancies complicated by intrauterine growth restriction. Data on the relationship between pathologic placental lesions and subsequent infant neurodevelopmental outcomes are limited.

OBJECTIVE

This study aimed to assess the relationship between placental pathologic lesions and infant neurodevelopmental outcomes at 2 years of age in a cohort of pregnancies complicated by intrauterine growth restriction.

STUDY DESIGN

An observational cohort study included singleton intrauterine growth restriction pregnancies delivered at ≤34 weeks' gestation and with a birthweight of ≤1500 g at a single institution in the period between 2007 and 2016. Maternal and neonatal data were collected at discharge from the hospital. Infant neurodevelopmental assessment was performed every 3 months during the first year of life and every 6 months in the second year. Penalized logistic regression was used to test the association of maternal vascular malperfusion and fetal vascular malperfusion with infant outcomes adjusting for confounders.

RESULTS

Of the 249 pregnancies enrolled, neonatal mortality was 8.8% (22 of 249). Severe and overall maternal vascular malperfusion were 16.1% (40 of 249) and 31.7% (79 of 249), respectively. Severe maternal vascular malperfusion was associated with an increased risk of neonatal mortality (adjusted odds ratio, 3.3; 95% confidence interval, 1.2-9.5). Among the 198 survivors after a 2-year neurodevelopmental follow-up evaluation, the rate of major and minor neurodevelopmental sequelae was 57.1% (4 of 7) among severe fetal vascular malperfusion (adjusted odds ratio, 24.5; 95% confidence interval, 4.1-146), 44.8% (13 of 29) among overall fetal vascular malperfusion (adjusted odds ratio, 5.8; 95% confidence interval, 5.1-16.2), and 7.1% (12 of 169) in pregnancies without fetal vascular malperfusion. Infants born from pregnancies with fetal vascular malperfusion also had lower 2-year general quotient, personal-social, hearing and speech, and performance subscales scores than those without fetal vascular malperfusion. Finally, in the presence of fetal vascular malperfusion, the likelihood of a 2-year infant survival with normal neurodevelopmental outcomes was reduced by more than 70% (adjusted odds ratio, 0.29; 95% confidence interval, 0.14-0.63). Noticeably, 10 of the 20 subjects with a 2-year major neurodevelopmental impairment (3 of 4 with severe fetal vascular malperfusion) had little or no abnormal neurologic findings at discharge from neonatal intensive care unit.

CONCLUSION

In preterm intrauterine growth restriction, placental fetal vascular malperfusion is correlated with an increased risk of abnormal infant neurodevelopmental outcomes at 2 years of age even in the absence of brain lesions or neurologic abnormalities at discharge from the neonatal intensive care unit. In the case of a diagnosis of fetal vascular malperfusion, pediatricians and neurologists should be alerted to an increased risk of subsequent infant neurodevelopmental problems.

Chronic deciduitis in stillbirths: are there any specific clinical associations?

INTRODUCTION

Placental chronic deciduitis is a lesion consistent with the presence of plasma cells within the placental basal plate. It could be associated with adverse pregnancy outcomes, including stillbirth.

METHODS

We retrospectively evaluated a cohort of 180 antepartum stillborn cases from singleton pregnancies, with the aim of investigating the clinical-histopathological relationship. Placental slides were reviewed following the standard protocol proposed by the "Amsterdam consensus statement".

RESULTS

We observed an association between chronic deciduitis and lesions consistent with maternal vascular malperfusion, delayed villous maturation, villitis of unknown etiology and maternal autoimmunity.

CONCLUSIONS

The observed clinical-histopathological associations suggest that an extensive maternal investigation could improve the comprehension of factors interfering with the placental development and the increasing risk of adverse pregnancy outcomes. HighlightsChronic deciduitis is associated with lesions consistent with maternal vascular malperfusionChronic deciduitis is associated with delayed villous maturationChronic deciduitis is associated with villitis of unknown etiologyChronic deciduitis is associated with maternal autoimmunity.

Association of Self-Reported Physical Fitness during Late Pregnancy with Birth Outcomes and Oxytocin Administration during Labour-The GESTAFIT Project

We explored (a) the associations between self-reported maternal physical fitness and birth outcomes; (b) whether self-reported maternal physical fitness (PF) is related to the administration of oxytocin to induce or stimulate labour. Pregnant women from the GESTAFIT project randomized controlled trial (n = 117) participated in this prospective longitudinal study. Maternal physical fitness was assessed through the International Fitness Scale at the 34th gestational week. Maternal and neonatal birth outcomes and oxytocin administration were collected from the obstetric medical records. Umbilical arterial and venous cord blood gas were analysed immediately after birth. Self-reported overall fitness, cardiorespiratory fitness, muscular strength and flexibility were not related to any maternal and neonatal birth outcomes (all p > 0.05). Greater speed-agility was associated with a more alkaline arterial (p = 0.04) and venous (p = 0.02) pH in the umbilical cord blood. Women who were administered oxytocin to induce or stimulate labour reported lower cardiorespiratory fitness (p = 0.013, Cohen's d = 0.55; 95% confidence interval (CI): 0.14, 0.93) and flexibility (p = 0.040, Cohen´s d = 0.51; 95% CI: 0.09, 0.89) compared to women who were not administered oxytocin. Greater maternal physical fitness during pregnancy could be associated with better neonatal birth outcomes and lower risk of needing oxytocin administration.

Placental Histological Features and Neurodevelopmental Outcomes at Two Years in Very-Low-Birth-Weight Infants

BACKGROUND

We evaluated the rates of placental pathologic lesions and their relationship with two-year neurodevelopmental outcomes in very-low-birth-weight (VLBW) infants.

METHODS

This is a cohort observational study comprising 595 VLBW infants during 2007 to 2015. Neurodevelopmental assessment was carried out at 24 months corrected age.

RESULTS

In univariate analysis the rates of survival with normal neurodevelopmental outcomes were lower in pregnancies with severe histologic chorioamnionitis (38 of 43, 88.4% when compared with 305 of 450, 67.8%), severe maternal vascular malperfusion (MVM) (17 of 37, 45.9% when compared with 326/492, 66.3%), and intravillous hemorrhage (37 of 82, 45.1% when compared with 306 of 449, 68.1%). In logistic models, severe MVM (adjusted odds ratio [adj. OR] = 0.45, 95% confidence interval [CI] = 0.22 to 0.92), severe fetal vascular malperfusion (FVM) (adj. OR = 0.46, 95% CI = 0.22 to 0.45), and intravillous hemorrhage (adj. OR = 0.38, 95% CI = 0.22 to 0.62) were associated with lower rates of infant survival with normal neurodevelopmental outcome. FVM (adj. OR = 0.46, 95% CI = 0.21 to 0.97) and intravillous hemorrhage (adj. OR = 0.37, 95% CI = 0.22 to 0.62) were also the only placental lesions that were independent predictors of a lower rate of intact survival in stepwise analysis for prognostic factors of the entire cohort.

CONCLUSIONS

Placental pathologic findings such as severe MVM, FVM, and intravillous hemorrhage are significant predictors of neonatal survival and subsequent adverse neurodevelopmental outcomes. Data on the placental pathology could be useful in the neurodevelopmental follow-up of VLBW infants.

Different antecedents and neonatal condition in neonatal arterial ischemic stroke and hypoxic-ischemic neonatal encephalopathy

Objective

To define similarities and differences between neonatal arterial ischemic stroke (NAIS) and hypoxic‐ischemic neonatal encephalopathy (HINE).

Methods

A retrospective case‐control study was conducted of neonates born at 35 weeks or more and weighing 1800 g or more at a tertiary care university hospital, between 2005 and 2016, with NAIS (group A), perinatal asphyxia (PA) with Stage II–III HINE (group B), and PA with or without Stage I HINE (group C). Ante‐ and intrapartum data, neonatal characteristics, and placental histopathology were compared.

Results

Eleven neonates were identified in group A, 10 in group B, and 227 in group C. Sentinel events occurred exclusively in groups B (80%) and C (41.4%). Umbilical cord blood gas values and Apgar score were worse in groups B and C compared to group A. No group A neonates required resuscitation at birth, whereas all group B and one‐third of group C neonates did. Seizures developed only in neonates in groups A and B. One neonatal death occurred in group A. There were no significant differences in placental histopathology.

Conclusion

NAIS and PA/HINE cases have different intrapartum and neonatal features. PA does not seem necessary for the occurrence of NAIS. More research is needed regarding associated placental abnormalities.

Birth asphyxia does not seem necessary for neonatal arterial ischemic stroke occurrence. The two conditions have different ante‐/intrapartum and neonatal features.

Autism spectrum disorders in extremely preterm infants and placental pathology findings: a matched case-control study

BACKGROUND

The prevalence of autism spectrum disorders (ASD) is 5-fold higher in preterm (PT) infants born ≤28 weeks gestational age (GA) as compared to the general population. The relationship between placental pathologic lesions and ASD in PT infants has not been studied.

OBJECTIVES

The objective of this study was to determine the association of placental pathology with the occurrence of ASD in PT infants born ≤28 weeks GA.

STUDY DESIGN

A matched case-control study to identify confirmed ASD cases (n = 16) and matched controls (n = 48) born at Parkland Hospital between January 2012 and December 2015. Patients were matched using known variables associated with increased risk of ASD in PT infants. Placental histology from all births was reviewed.

RESULTS

Children with ASD had 2-fold greater incidence of multiple placental pathologic lesions vs. matched controls [11/16 (69%) vs.16/48 (33%), respectively; P = 0.01]. In contrast, single placental pathologic lesions were not associated with ASD [5/16 (31%) vs. 21/48 (43%), respectively; P = 0.1].

CONCLUSIONS

In this study, we have demonstrated an association between the increasing complexity of histologic placental lesions and the later risk for ASD in infants born ≤28 weeks GA. Thus, placental pathology findings may be valuable in further understanding the prenatal pathologic processes underlying ASD in PT infants.

IMPACT

PT infants with ASD have a 2-fold greater incidence of multiple placental pathologies. This is the first study to report an association between the complexity of histologic placental lesions and later risk of ASD in infant born extremely PT (i.e., ≤28 weeks GA). This study reiterates the importance of examining placental pathologic lesions, since placental evidence of antenatal insults correlates with postnatal morbidities and mortality in PT infants.

Placental pathology and intraventricular hemorrhage in preterm and small for gestational age infants

OBJECTIVE

The aim of this study was to examine the relationship between chorioamnionitis and vascular malperfusion on placental pathology and intraventricular hemorrhage (IVH) in premature and small for gestational age (SGA) infants.

STUDY DESIGN

A retrospective analysis of 263 infants ≤34 weeks gestation or ≤1800 g and their mothers was conducted by chart review for placental pathology and clinical data from 2014 to 2018. Unadjusted and adjusted odds ratios (OR) for the association of placental pathology with IVH were calculated.

RESULT

Unadjusted OR showed an association between acute chorioamnionitis and IVH, but logistic regression analysis showed a non-significant adjusted OR between acute or chronic chorioamnionitis with IVH. Maternal vascular malperfusion was significantly associated with increased IVH when controlling for confounders.

CONCLUSION

Placental maternal vascular malperfusion is associated with the development of IVH in premature and SGA infants when controlling for other confounders.

Placental origins of neonatal diseases: toward a precision medicine approach

The placenta is the single most reliable source for precise information on intrauterine environment, as well as maternal and fetal health. It mediates the physiology of two distinct yet highly interconnected individuals. The pathology that develops in the placenta, and the adaptations the placenta undergoes to mitigate this pathology, may influence the later life health of the mother and baby. Pathological placental examination provides a unique opportunity to explore and understand the intrauterine environment, as well as providing a record of events that may be associated with adverse pregnancy outcomes. A number of placental lesions have been described in association with various neonatal morbidities. The purpose of this review is to summarize the evidence for the association of placental pathologic lesions with neurodevelopmental outcomes infants with specific neonatal morbidities, including (1) neonatal encephalopathy, (2) bronchopulmonary dysplasia, (3) congenital heart diseases, and (4) autism spectrum disorders. For each of these disease processes, we will also propose specific research priorities in future studies. We conclude with a hospital-specific protocol for triaging which placentas should receive histological evaluation as a fundamental first step for the field of neuroplacentology to guide precision-based therapeutic approaches in the affected newborns. IMPACT: The purpose of this review is to summarize the evidence for placental origins of neonatal diseases. We propose specific research priorities in the field of neuroplacentology in future studies. We also present a targeted hospital-based approach for triaging which placentas should receive histological evaluation.

"The First Thousand Days" Define a Fetal/Neonatal Neurology Program

Gene-environment interactions begin at conception to influence maternal/placental/fetal triads, neonates, and children with short- and long-term effects on brain development. Life-long developmental neuroplasticity more likely results during critical/sensitive periods of brain maturation over these first 1,000 days. A fetal/neonatal program (FNNP) applying this perspective better identifies trimester-specific mechanisms affecting the maternal/placental/fetal (MPF) triad, expressed as brain malformations and destructive lesions. Maladaptive MPF triad interactions impair progenitor neuronal/glial populations within transient embryonic/fetal brain structures by processes such as maternal immune activation. Destructive fetal brain lesions later in pregnancy result from ischemic placental syndromes associated with the great obstetrical syndromes. Trimester-specific MPF triad diseases may negatively impact labor and delivery outcomes. Neonatal neurocritical care addresses the symptomatic minority who express the great neonatal neurological syndromes: encephalopathy, seizures, stroke, and encephalopathy of prematurity. The asymptomatic majority present with neurologic disorders before 2 years of age without prior detection. The developmental principle of ontogenetic adaptation helps guide the diagnostic process during the first 1,000 days to identify more phenotypes using systems-biology analyses. This strategy will foster innovative interdisciplinary diagnostic/therapeutic pathways, educational curricula, and research agenda among multiple FNNP. Effective early-life diagnostic/therapeutic programs will help reduce neurologic disease burden across the lifespan and successive generations.

The effect of Ipomoea carnea on maternal reproductive outcomes and fetal and postnatal development in rats

Ipomoea carnea is a toxic plant found in Brazil and other tropical countries. The plant contains the alkaloids calystegines and swainsonine, which inhibit key cellular enzymes and cause systematic cell death. It is known that swainsonine is excreted in the amniotic fluid of dams exposed to the plant. Thus, the aim of this study was to verify whether the toxic effect of I. carnea on fetuses is due to exclusively the passage of the active principle of the plant through the placenta, or if the placentotoxic effect of swainsonine could collaborate in the adverse effects observed in the fetus. The teratogenic effects of exposure to the toxic principles of I. carnea were evaluated not only using the conventional protocol but also at later stages in the postnatal developmental period. Females were treated, from gestation day (GD) 6 until GD19, with 0.0, 1.0, 3.0 or 7.0 g/kg body weight of I. carnea dry leaves. The plant did not induce changes in reproductive performance or biochemical profile of the dams. Dams that received the highest dose of I. carnea showed cytoplasmic vacuolization in the liver, kidney and placental tissue. I. carnea promoted different lectin binding patterns in different areas of placental tissue. No fetal skeletal or visceral malformations was observed. The postnatal evaluation revealed a lower litter weight and a lower pup body weight one day after birth in the group that received the highest dose of I. carnea. Physical milestones were unaffected by the treatments. Female pups from all experimental groups exhibited a delay in achieving a negative geotaxis response. The results show that the toxic principle of I. carnea produces injury in utero in mothers and fetuses, but these deleterious effects were better demonstrated using postnatal evaluation.

Maternal-Fetal Inflammation in the Placenta and the Developmental Origins of Health and Disease

Events in fetal life impact long-term health outcomes. The placenta is the first organ to form and is the site of juxtaposition between the maternal and fetal circulations. Most diseases of pregnancy are caused by, impact, or are reflected in the placenta. The purpose of this review is to describe the main inflammatory processes in the placenta, discuss their immunology, and relate their short- and long-term disease associations. Acute placental inflammation (API), including maternal and fetal inflammatory responses corresponds to the clinical diagnosis of chorioamnionitis and is associated with respiratory and neurodevelopmental diseases. The chronic placental inflammatory pathologies (CPI), include chronic villitis of unknown etiology, chronic deciduitis, chronic chorionitis, eosinophilic T-cell vasculitis, and chronic histiocytic intervillositis. These diseases are less-well studied, but have complex immunology and show mechanistic impacts on the fetal immune system. Overall, much work remains to be done in describing the long-term impacts of placental inflammation on offspring health.

Histologic chorioamnionitis and risk of neurodevelopmental impairment at age 10 years among extremely preterm infants born before 28 weeks of gestation

BACKGROUND

Extremely preterm infants whose placenta had histologic evidence of chorioamnionitis have early brain dysfunction, but little is known about neurologic development at 10 years of age.

OBJECTIVE

We investigated the association between histologic chorioamnionitis and neurodevelopmental impairment at 10 years among children born <28 weeks' gestation (extremely preterm).

STUDY DESIGN

The multicenter Extremely Low Gestational Age Newborns study enrolled extremely preterm newborns from 2002 to 2004 at 14 hospitals in the United States. Chorioamnionitis was defined by histologic stage (early, moderate, and advanced) and grade (mild/moderate and severe) of chorionic plate and umbilical cord inflammation. The children were examined for cerebral palsy at 2 years and for autism spectrum disorder, cognitive impairment (intelligence quotient >2 standard deviations below the mean), and epilepsy at the age of 10 years by blinded evaluators using validated measures. Multivariable logistic regression with generalized estimating equations was used.

RESULTS

Among 805 placentas, 43% (347/805) had histologic chorioamnionitis by moderate or advanced maternal stage, 36% (286/805) by severe maternal grade, 18% (132/737) by moderate or advanced fetal stage, and 1% (10/737) by severe fetal grade. The frequencies of impairments were 11% (88/767) for cerebral palsy, 7% (56/773) for autism spectrum disorder, 15% (120/788) for cognitive impairment, and 7% (52/763) for epilepsy. After adjustment for maternal age, body mass index, race, insurance status, maternal education, tobacco use, infant sex, and multiple gestations, the adjusted odds ratio for the association between histologic chorioamnionitis and cerebral palsy years was increased with advanced maternal stage (adjusted odds ratio, 2.5; 95% confidence interval, 1.6-3.9), severe maternal grade (adjusted odds ratio, 2.0; 95% confidence interval, 1.2-3.4), moderate fetal stage (adjusted odds ratio, 2.20; 95% confidence interval, 2.1-2.2), and mild or moderate fetal grade (adjusted odds ratio, 1.5; 95% confidence interval, 1.0-2.2). Similarly, the adjusted odds ratio for the association between histologic chorioamnionitis and epilepsy was increased with advanced maternal stage (adjusted odds ratio, 1.5; 95% confidence interval, 1.3-1.6) and severe fetal grade (adjusted odds ratio, 5.9; 95% confidence interval, 1.9-17.8). In addition, the adjusted odds ratio for the association between histologic chorioamnionitis and autism spectrum disorder was increased with mild or moderate fetal grade (adjusted odds ratio, 1.7; 95% confidence interval, 1.0-2.9). Histologic chorioamnionitis was not associated with cognitive impairment. These findings held after adjustment for gestational age at delivery. In contrast to histologic chorioamnionitis, a clinical diagnosis of chorioamnionitis was not associated with neurodevelopmental impairment.

CONCLUSION

Histologic chorioamnionitis may be associated with some forms of neurodevelopmental impairment at 10 years of life among infants born <28 weeks' gestation.

Perinatal Arterial Ischemic Stroke in Fetal Vascular Malperfusion: A Case Series and Literature Review

Fetal vascular malperfusion includes a continuum of placental histologic abnormalities increasingly associated with perinatal brain injury, namely arterial ischemic stroke. Here, we describe the clinical-neuroimaging features of 5 neonates with arterial ischemic stroke and histologically proved fetal vascular malperfusion. All infarcts involved the anterior territories and were multiple in 2 patients. In 2 neonates, there were additional signs of marked dural sinus congestion, thrombosis, or both. A mixed pattern of chronic hypoxic-ischemic encephalopathy and acute infarcts was noted in 1 patient at birth. Systemic cardiac or thrombotic complications were present in 2 patients. These peculiar clinical-radiologic patterns may suggest fetal vascular malperfusion and should raise the suspicion of this rare, underdiagnosed condition carrying important implications in patient management, medicolegal actions, and future pregnancy counseling.

Association between Placental Inflammatory Pathology and Offspring Neurodevelopment at 8 Months and 4 and 7 Years of Age

OBJECTIVE

To examine whether placental inflammatory pathology is associated with subsequent child neurodevelopment.

STUDY DESIGN

We used the data of US Collaborative Perinatal Project cohort study. Placentas were examined by pathologists and child neurodevelopment was evaluated at 8 months and 4 and 7 years of age. Multivariable logistic regression modelling was used to assess the association. A mediation analysis was used to evaluate whether the association was mediated through shorter gestational age.

RESULTS

Multivariable analysis after adjusting for confounders showed that placental inflammatory pathology was significantly associated with low Bayley motor (adjusted OR (aOR), 2.15; 95% CI, 1.50-3.06) and mental scales (aOR, 1.51; 95% CI, 1.05-2.17) at 8 months and an IQ of 70-84 (aOR, 1.13; 95% CI, 1.01-1.26) at 4 years of age. The association diminished at 7 years of age (IQ of <70, aOR 1.20 [95% CI, 0.97-1.48]; IQ of 70-79, aOR 1.03 [95% CI, 0.89-1.18]). The mediation analysis demonstrated that associations between placental inflammatory pathology and development were primarily due to direct effects of placental inflammatory pathology rather than indirect effects of shorter gestational age.

CONCLUSIONS

Placental inflammation was associated with adverse offspring neurodevelopment up to 4 years of age.