Neonatal Morbidities of Fetal Growth Restriction: Pathophysiology and Impact

The placental blood perfusion and LINC00473-mediated promotion of trophoblast apoptosis in fetal growth restriction

This study aimed to investigate placental microblood flow perfusion in fetal growth restriction (FGR) both pre- and post-delivery, and explore the influence of LINC00473 and its downstream targets on FGR progression in trophoblast cells. Placental vascular distribution, placental vascular index (VIMV), CD34 expression, and histological changes were compared between control and FGR groups. FGR-related differentially expressed genes (DEGs) were analyzed and validated by quantitative real-time polymerase chain reaction (qPCR) and immunohistochemistry (IHC) in placentae. In vitro experiments examined the regulatory relationships among LINC00473, miR-5189-5p, and StAR, followed by investigations into their impacts on cell proliferation and apoptosis. FGR placentae exhibited irregular shapes, uneven parenchymal echo, stromal dysplasia, ischemic infarction, and variable degrees of thickening in some cases. FGR samples showed less prominent mother vessel lakes, significantly lower VIMV, and decreased CD34 expression. Hematoxylin & eosin (H&E) staining revealed placental fibrosis, fibrin adhesion, infarction, and interstitial dysplasia in FGR. LINC00473, miR-5189-5p, and StAR were identified as DEG, with qPCR demonstrating a significant increase in LINC00473 and a decrease in miR-5189-5p in FGR, while both qPCR and IHC indicated a significant increase in StAR expression. LINC00473 served as an endogenous sponge against miR-5189-5p in human HTR-8/SV neo cells, and StAR expression was regulated by both LINC00473 and miR-5189-5p. Dysregulation of these genes affected cell proliferation and apoptosis. Pathological changes in the placenta are significant contributors to FGR, with placental microblood flow potentially serving as an indicator for monitoring its progression. LINC00473 and its downstream targets may modulate trophoblasts proliferation and apoptosis, thus influencing the onset of FGR, suggesting novel avenues for diagnosis and treatment.

The Impact of Fetal Growth Restriction on Prenatal 2D Ultrasound and Doppler Study of the Fetal Adrenal Gland

Background: Uteroplacental insufficiency in fetuses with growth restriction (FGR) leads to chronic hypoxia and stress, predominantly affecting the adrenal glands. However, the mechanisms of impact remain unclear. Objectives: This study is aimed at comparing the Doppler indices of the adrenal artery and the adrenal gland sizes between FGR and those with normal growth. Materials and Methods: A multicenter, cross-sectional study was conducted from February to December 2023. We compared 34 FGR to 34 with normal growth in terms of inferior adrenal artery (IAA) Doppler indices and adrenal gland volumes. Results: The IAA peak systolic velocity (PSV) in the FGR group was 14.9 ± 2.9 cm/s compared to 13.5 ± 2.0 cm/s in the normal group, with a mean difference of 1.4 cm/s (95% confidence interval [CI]: 0.27-2.65; p value = 0.017). There were no significant differences between groups in terms of IAA pulsatility index (PI), resistance index (RI), or systolic/diastolic (S/D), with p values of 0.438, 0.441, and 0.658, respectively. The volumes of the corrected whole adrenal gland and the corrected neocortex were significantly larger in the FGR group, with p values of 0.031 and 0.020, respectively. Conclusion: Both increased IAA PSV and enlarged volumes of the corrected whole adrenal gland and neocortex were found in fetuses with FGR, suggesting significant adrenal gland adaptation in response to chronic intrauterine stress.

Maternal gut Bifidobacterium breve modifies fetal brain metabolism in germ-free mice

BACKGROUND

Recent advances have significantly expanded our understanding of the gut microbiome's influence on host physiology and metabolism. However, the specific role of certain microorganisms in gestational health and fetal development remains underexplored.

OBJECTIVE

This study investigates the impact of Bifidobacterium breve UCC2003 on fetal brain metabolism when colonized in the maternal gut during pregnancy.

METHODS

Germ-free pregnant mice were colonized with or without B. breve UCC2003 during pregnancy. The metabolic profiles of fetal brains were analyzed, focusing on the presence of key metabolites and the expression of critical metabolic and cellular pathways.

RESULTS

Maternal colonization with B. breve resulted in significant metabolic changes in the fetal brain. Specifically, ten metabolites, including citrate, 3-hydroxyisobutyrate, and carnitine, were reduced in the fetal brain. These alterations were accompanied by increased abundance of transporters involved in glucose and branched-chain amino acid uptake. Furthermore, supplementation with this bacterium was associated with elevated expression of critical metabolic pathways such as PI3K-AKT, AMPK, STAT5, and Wnt-β-catenin signaling, including its receptor Frizzled-7. Additionally, there was stabilization of HIF-2 protein and modifications in genes and proteins related to cellular growth, axogenesis, and mitochondrial function.

CONCLUSIONS

The presence of maternal B. breve during pregnancy plays a crucial role in modulating fetal brain metabolism and growth. These findings suggest that Bifidobacterium could modify fetal brain development, potentially offering new avenues for enhancing gestational health and fetal development through microbiota-targeted interventions.

Fetal growth restriction induced by maternal gal-3 deficiency is associated with altered gut-placenta axis

Adverse intrauterine conditions may cause fetal growth restriction (FGR), a pregnancy complication frequently linked to perinatal morbidity and mortality. Although many studies have focused on FGR, the pathophysiological processes underlying this disorder are complex and incompletely understood. We have recently determined that galectin-3 (gal-3), a β-galactoside-binding protein, regulates pregnancy-associated processes, including uterine receptibility, maternal vascular adaptation and placentation. Because gal-3 is expressed at both sides of the maternal-fetal interface, we unraveled the contribution of maternal- and paternal-derived gal-3 on fetal-placental development in the prenatal window and its effects on the post-natal period. Deficiency of maternal gal-3 induced maternal gut microbiome dysbiosis, resulting in a sex-specific fetal growth restriction mainly observed in female fetuses and offspring. In addition, poor placental metabolic adaptions (characterized by decreased trophoblast glycogen content and insulin-like growth factor 2 (Igf2) gene hypomethylation) were only associated with a lack of maternal-derived gal-3. Paternal gal-3 deficiency caused compromised vascularization in the placental labyrinth without affecting fetal growth trajectory. Thus, maternal-derived gal-3 may play a key role in fetal-placental development through the gut-placenta axis.

The effects of radiofrequency exposure on adverse female reproductive outcomes: A systematic review of human observational studies with dose-response meta-analysis

BACKGROUND

To inform radiofrequency electromagnetic field (RF-EMF) exposure guidelines the World Health Organization (WHO) is bringing together evidence on RF-EMF in relation to health outcomes prioritised for evaluation by experts in this field. Given this, a network of topic experts and methodologists have conducted a series of systematic reviews collecting, assessing, and synthesising data of relevance to these guidelines. Here we present a systematic review of the effect of RF-EMF exposure on adverse pregnancy outcomes in human observational studies which follows the WHO handbook for guideline development and the COSTER conduct guidelines.

METHODS

We conducted a broad, sensitive search for potentially relevant records within the following bibliographic databases: MEDLINE; Embase; and the EMF Portal. Grey literature searches were also conducted through relevant databases (including OpenGrey), organisational websites and via consultation of RF-EMF experts. We included quantitative human observational studies on the effect of RF-EMF exposure in adults' preconception or pregnant women on pre-term birth, small for gestational age (SGA; associated with intrauterine growth restriction), miscarriage, stillbirth, low birth weight (LBW) and congenital anomalies. In blinded duplicate, titles and abstracts then full texts were screened against eligibility criteria. A third reviewer gave input when consensus was not reached. Citation chaining of included studies was completed. Two reviewers' data extracted and assessed included studies for risk of bias using the Office of Health Assessment and Translation (OHAT) tool. Random effects meta-analyses of the highest versus the lowest exposures and dose-response meta-analysis were conducted as appropriate and plausible. Two reviewers assessed the certainty in each body of evidence using the OHAT GRADE tool.

RESULTS

We identified 18 studies in this review; eight were general public studies (with the general public as the population of interest) and 10 were occupational studies (with the population of interest specific workers/workforces). General public studies. From pairwise meta-analyses of general public studies, the evidence is very uncertain about the effects of RF-EMF from mobile phone exposure on preterm birth risk (relative risk (RR) 1.14, 95% confidence interval (CI): 0.97-1.34, 95% prediction interval (PI): 0.83-1.57; 4 studies), LBW (RR 1.14, 95% CI: 0.96-1.36, 95% PI: 0.84-1.57; 4 studies) or SGA (RR 1.13, 95% CI: 1.02-1.24, 95% PI: 0.99-1.28; 2 studies) due to very low-certainty evidence. It was not feasible to meta-analyse studies reporting on the effect of RF-EMF from mobile phone exposure on congenital anomalies or miscarriage risk. The reported effects from the studies assessing these outcomes varied and the studies were at some risk of bias. No studies of the general public assessed the impact of RF-EMF exposure on stillbirth. Occupational studies. In occupational studies, based on dose-response meta-analyses, the evidence is very uncertain about the effects of RF-EMF amongst female physiotherapists using shortwave diathermy on miscarriage due to very low-certainty evidence (OR 1.02 95% CI 0.94-1.1; 2 studies). Amongst offspring of female physiotherapists using shortwave diathermy, the evidence is very uncertain about the effects of RF-EMF on the risk of congenital malformations due to very low-certainty evidence (OR 1.4, 95% CI 0.85 to 2.32; 2 studies). From pairwise meta-analyses, the evidence is very uncertain about the effects of RF-EMF on the risk of miscarriage (RR 1.06, 95% CI 0.96 to 1.18; very low-certainty evidence), pre-term births (RR 1.19, 95% CI 0.32 to 4.37; 3 studies; very low-certainty evidence), and low birth weight (RR 2.90, 95% CI: 0.69 to 12.23; 3 studies; very low-certainty evidence). Results for stillbirth and SGA could not be pooled in meta-analyses. The results from the studies reporting these outcomes were inconsistent and the studies were at some risk of bias.

DISCUSSION

Most of the evidence identified in this review was from general public studies assessing localised RF-EMF exposure from mobile phone use on female reproductive outcomes. In occupational settings, each study was of heterogenous whole-body RF-EMF exposure from radar, short or microwave diathermy, surveillance and welding equipment and its effect on female reproductive outcomes. Overall, the body of evidence is very uncertain about the effect of RF-EMF exposure on female reproductive outcomes. Further prospective studies conducted with greater rigour (particularly improved accuracy of exposure measurement and using appropriate statistical methods) are required to identify any potential effects of RF-EMF exposure on female reproductive outcomes of interest.

Impact on neonatal morbidity of moderate to severe early foetal growth restriction defined by doppler criteria: multicentre study

INTRODUCTION

In recent years, there has been a change in the conceptualization of foetal growth restriction (FGR), which has gone from being defined solely based on weight criteria to being defined and staged based on Doppler criteria. The aim of our study was to evaluate neonatal risk in a cohort of neonates with moderate to severe early-onset FGR defined by Doppler criteria.

POPULATION AND METHODS

We conducted a multicentre prospective cohort study in a cohort of neonates with early-onset foetal growth restriction and abnormal Doppler findings and a control cohort without Doppler abnormalities matched for sex and gestational age.

RESULTS

A total of 105 patients (50 cases, 55 controls) were included. We found a higher frequency of respiratory morbidity in the FGR group, with an increased need of surfactant (30% vs. 27.3%; OR, 5.3 [95% CI, 1.1-26.7]), an increased need for supplemental oxygen (66% vs. 49.1%; OR, 5.6 [95% CI, 1.5-20.5]), and a decreased survival without bronchopulmonary dysplasia (70 vs. 87.3%; OR, 0.16 [95% CI, 0.03-0.99]). Patients with FGR required a longer length of stay and more days of parenteral nutrition and had a higher incidence of haematological abnormalities such as neutropenia and thrombopenia. The lactate level at birth was higher in the severe FGR subgroup (6.12 vs. 2.4 mg/dL; P = .02).

CONCLUSION

The diagnosis of early-onset moderate to severe FGR defined by Doppler criteria carries a greater risk of respiratory, nutritional and haematological morbidity, independently of weight and gestational age. These patients, therefore, should be considered at increased risk compared to constitutionally small for gestational age preterm infants or preterm infants without FGR.

Unisex and Sex-Specific Prescriptive Fetal Growth Charts for Improved Detection of Small-for-Gestational-Age Babies in a Low-Risk Population: A post hoc Analysis of a Cluster-Randomized Study

INTRODUCTION

Our aim was to develop and evaluate the performance of population-based sex-specific and unisex prescriptive fetal abdominal circumference growth charts in predicting small-for-gestational-age (SGA) birthweight, severe SGA (sSGA) birthweight, and severe adverse perinatal outcomes (SAPO) in a low-risk population.

METHODS

This is a post hoc analysis of the Dutch nationwide cluster-randomized IRIS study, encompassing ultrasound data of 7,704 low-risk women. IRIS prescriptive unisex and IRIS sex-specific abdominal circumference (AC) fetal growth charts were derived using quantile regression. As a comparison, we used the descriptive unisex Verburg chart, which is commonly applied in the Netherlands. Diagnostic parameters were calculated based on the 34-36 weeks' ultrasound.

RESULTS

Sensitivity rates for predicting SGA and sSGA birthweights were more than twofold higher based on the IRIS prescriptive sex-specific (respectively SGA 43%; sSGA 59%) and unisex (SGA 39%; sSGA 55%) charts, compared to the Verburg chart (SGA 16%; sSGA 23% both p < 0.01). Specificity rates were highest for Verburg (SGA 99%; sSGA 98%) and lowest for IRIS sex-specific (SGA 94%; sSGA 92%). Results for predicting SGA with SAPO were similar for the prescriptive charts (44%), and again higher than the Verburg chart (20%). The IRIS sex-specific chart identified significantly more males as SGA and sSGA (respectively, 42%; 60%, p < 0.001) than the IRIS unisex chart (respectively, 35%; 53% p < 0.01).

CONCLUSION

Our study demonstrates improved performance of both the IRIS sex-specific and unisex prescriptive fetal growth compared to the Verburg descriptive chart, doubling detection rates of SGA, sSGA, and SGA with SAPO. Additionally, the sex-specific chart outperformed the unisex chart in detecting SGA and sSGA. Our findings suggest the potential benefits of using prescriptive AC fetal growth charts in low-risk populations and emphasize the importance of considering customizing fetal growth charts for sex. Nevertheless, the increased sensitivity of these charts should be weighed against the decrease in specificity.

SPAG7 deletion causes intrauterine growth restriction, resulting in adulthood obesity and metabolic dysfunction

From a forward mutagenetic screen to discover mutations associated with obesity, we identified mutations in the Spag7 gene linked to metabolic dysfunction in mice. Here, we show that SPAG7 KO mice are born smaller and develop obesity and glucose intolerance in adulthood. This obesity does not stem from hyperphagia, but a decrease in energy expenditure. The KO animals also display reduced exercise tolerance and muscle function due to impaired mitochondrial function. Furthermore, SPAG7-deficiency in developing embryos leads to intrauterine growth restriction, brought on by placental insufficiency, likely due to abnormal development of the placental junctional zone. This insufficiency leads to loss of SPAG7-deficient fetuses in utero and reduced birth weights of those that survive. We hypothesize that a 'thrifty phenotype' is ingrained in SPAG7 KO animals during development that leads to adult obesity. Collectively, these results indicate that SPAG7 is essential for embryonic development and energy homeostasis later in life.

Plasma metabolites are altered before and after diagnosis of preeclampsia or fetal growth restriction

Metabolomics is the study of small molecules (metabolites), within cells, tissues and biofluids. Maternal metabolites can provide important insight into the health and development of both mother and fetus throughout pregnancy. This study assessed metabolic profiles in the maternal circulation prior to and at the time of diagnosis of preeclampsia and fetal growth restriction. Maternal plasma samples were collected from two independent cohorts: (1) Established disease cohort: 50 participants diagnosed with early-onset preeclampsia (< 34 weeks' gestation), 14 with early-onset fetal growth restriction, and 25 gestation-matched controls. (2) Prospective cohort, collected at 36 weeks' gestation before diagnosis: 17 participants later developed preeclampsia, 49 delivered infants with fetal growth restriction (birthweight < 5th centile), and 72 randomly selected controls. Metabolic evaluation was performed by Metabolomics Australia on the Agilent 6545 QTOF Mass Spectrometer. In the established disease cohort, 77 metabolites were altered in circulation from participants with preeclampsia - increased L-cysteine (3.73-fold), L-cystine (3.28-fold), L-acetylcarnitine (2.57-fold), and carnitine (1.53-fold) (p < 0.05). There were 53 metabolites dysregulated in participants who delivered a fetal growth restriction infant-including increased levulinic acid, citric acid (1.93-fold), and creatine (1.14-fold) (p < 0.05). In the prospective cohort, 30 metabolites were altered in participants who later developed preeclampsia at term - reduced glutaric acid (0.85-fold), porphobilinogen (0.77-fold) and amininohippuric acid (0.82-fold) (p < 0.05) was observed. There were 5 metabolites altered in participants who later delivered a fetal growth restriction infant - including reduced 3-methoxybenzenepropanoic acid (p < 0.05). Downstream pathway analysis revealed aminoacyl-tRNA biosynthesis to be most significantly altered in the established cohort in preeclampsia (13/48 hits, p < 0.001) and fetal growth restriction (7/48 hits, p < 0.001). The predictive cohort showed no significant pathway alterations. This study observed altered metabolites in maternal plasma collected before and after diagnosis of a preeclampsia or fetal growth restriction. While a significant number of metabolites were altered with established disease, few changes were observed in the predictive cohort. Thus, metabolites measured in this study may not be useful as predictors of preeclampsia or fetal growth restriction.

Correlation of fetal lung area with MRI derived pulmonary volume

BACKGROUND

Neonatal chest-Xray (CXR)s are commonly performed as a first line investigation for the evaluation of respiratory complications. Although lung area derived from CXRs correlates well with functional assessments of the neonatal lung, it is not currently utilised in clinical practice, partly due to the lack of reference ranges for CXR-derived lung area in healthy neonates. Advanced MR techniques now enable direct evaluation of both fetal pulmonary volume and area. This study therefore aims to generate reference ranges for pulmonary volume and area in uncomplicated pregnancies, evaluate the correlation between prenatal pulmonary volume and area, as well as to assess the agreement between antenatal MRI-derived and neonatal CXR-derived pulmonary area in a cohort of fetuses that delivered shortly after the antenatal MRI investigation.

METHODS

Fetal MRI datasets were retrospectively analysed from uncomplicated term pregnancies and a preterm cohort that delivered within 72 h of the fetal MRI. All examinations included T2 weighted single-shot turbo spin echo images in multiple planes. In-house pipelines were applied to correct for fetal motion using deformable slice-to-volume reconstruction. An MRI-derived lung area was manually segmented from the average intensity projection (AIP) images generated. Postnatal lung area in the preterm cohort was measured from neonatal CXRs within 24 h of delivery. Pearson correlation coefficient was used to correlate MRI-derived lung volume and area. A two-way absolute agreement was performed between the MRI-derived AIP lung area and CXR-derived lung area.

RESULTS

Datasets from 180 controls and 10 preterm fetuses were suitable for analysis. Mean gestational age at MRI was 28.6 ± 4.2 weeks for controls and 28.7 ± 2.7 weeks for preterm neonates. MRI-derived lung area correlated strongly with lung volumes (p < 0.001). MRI-derived lung area had good agreement with the neonatal CXR-derived lung area in the preterm cohort [both lungs = 0.982].

CONCLUSION

MRI-derived pulmonary area correlates well with absolute pulmonary volume and there is good correlation between MRI-derived pulmonary area and postnatal CXR-derived lung area when delivery occurs within a few days of the MRI examination. This may indicate that fetal MRI derived lung area may prove to be useful reference ranges for pulmonary areas derived from CXRs obtained in the perinatal period.

Prenatal exposure to persistent and non-persistent chemical mixtures and associations with adverse birth outcomes in the Atlanta African American Maternal-Child Cohort

BACKGROUND

African Americans (AAs) experience higher rates of preterm birth and fetal growth restriction relative to other pregnant populations. Differential in utero exposure to environmental chemicals may partially explain these health disparities, as AAs are disproportionately exposed to environmental hazards.

OBJECTIVE

We examined the individual and mixture effects of non-persistent chemicals and persistent organic pollutants (POPs) on gestational age at birth and birthweight for gestational age z-scores within a prospective cohort of pregnant AAs.

METHODS

First-trimester serum and urine samples obtained from participants within the Atlanta African American Maternal-Child cohort were analyzed for 43 environmental chemicals, including per-and polyfluoroalkyl substances (PFAS), polybrominated diphenyl ethers (PBDEs), organochlorine pesticides, pyrethroid insecticides, phthalates, bisphenol A, nicotine, and the primary metabolite of delta-9-tetrahydrocannabinol. Linear regression was used to estimate individual associations between chemicals and gestational age and birthweight z-scores (N ranging from 107 to 523). Mixture associations were estimated using quantile g-computation, principal component (PC) analyses, and hierarchical Bayesian kernel machine regression among complete cases (N = 86).

RESULTS

Using quantile g-computation, increasing all chemical exposures by one quantile was modestly associated with a reduction in gestational age (mean change per quartile increase = -0.47, 95% CI = -1.56, 0.61) and birthweight z-scores (mean change per quartile increase = -0.49, 95% CI = -1.14, 0.15). All PCs were associated with a reduction in birthweight z-scores; associations were greatest in magnitude for the two PCs reflecting exposure to combined tobacco, insecticides, PBDEs, and phthalates. In single pollutant models, we observed inconsistent and largely non-significant associations.

SIGNIFANCE

We conducted multiple targeted exposure assessment methods to quantify levels of environmental chemicals and leveraged mixture methods to quantify their joint effects on gestational age and birthweight z-scores. Our findings suggest that prenatal exposure to multiple classes of persistent and non-persistent chemicals is associated with reduced gestational age and birthweight z-scores in AAs.

IMPACT

African Americans (AAs) experience higher rates of preterm birth and fetal growth restriction relative to other pregnant populations. Differential in utero exposure to environmental chemicals may partially explain these health disparities, as AAs are disproportionately exposed to environmental hazards. In the present study, we analyzed serum and urine samples for levels of 43 environmental chemicals. We used quantile g-computation, principal component analysis, and BKMR to assess associations between chemical exposure mixtures and adverse birth outcomes. Our findings suggest that prenatal exposure to multiple classes of chemicals is associated with reduced birthweight z-scores, a proxy for fetal growth, in AAs.

Hemostatic Status of Neonates with Perinatal Hypoxia, Studied via NATEM in Cord Blood Samples

BACKGROUND

Perinatal hypoxia may result in coagulation dysfunction. Diminished blood flow or oxygen to the fetus/neonate during the perinatal period can cause bone marrow and liver function impairment, leading to thrombocytopenia, impaired synthesis of clotting and fibrinolytic factors, and increased destruction of platelets in the small blood vessels. The goal of the present study was to evaluate the hemostatic status of newborns with perinatal hypoxia via the non-activated thromboelastometry (NATEM) assay in cord blood samples.

METHODS

134 hypoxic neonates born in our maternity unit over a 1.5-year period were enrolled in this observational cohort study, and 189 healthy neonates served as the control group. Participation in the study was voluntary and parents signed informed consent prior to recruitment. Demographic and clinical data were recorded on admission, and the NATEM method was performed on cord blood samples. The following NATEM values were evaluated: clotting time (CT), alpha angle (α-angle), clot formation time (CFT), clot amplitude at 5 and 10 min. (A5, A10), maximum clot firmness (MCF), clot lysis index at 60 min. after CT (LI60), and maximum clot elasticity (MCE). Statistical analysis was conducted utilizing the SAS for Windows 9.4 software platform.

RESULTS

Neonates with perinatal hypoxia exhibited decreased fibrinolytic potential in comparison to healthy neonates, as indicated by increased LI60, and this difference was statistically significant (LΙ60: 94 (92-96) Vs 93 (91-95), p value = 0.0001). There were no statistically significant differences noted among the remaining NATEM variables.

CONCLUSION

Our findings indicate decreased fibrinolytic potential in hypoxic neonates in comparison to healthy neonates, suggesting that NATEM could serve as an effective tool for promptly identifying hemostasis dysfunction in this group of neonates.

The search for blood biomarkers that indicate risk of adverse neurodevelopmental outcomes in fetal growth restriction

Fetal growth restriction (FGR) impacts 5%-10% of pregnancies and is associated with increased risk of mortality and morbidity. Although adverse neurodevelopmental outcomes are observed in up to 50% of FGR infants, a diagnosis of FGR does not indicate the level of risk for an individual infant and these infants are not routinely followed up to assess neurodevelopmental outcomes. Identifying FGR infants at increased risk of adverse neurodevelopmental outcomes would greatly assist in providing appropriate support and interventions earlier, resulting in improved outcomes. However, current methods to detect brain injury around the time of birth lack the sensitivity required to detect the more subtle alterations associated with FGR. Blood biomarkers have this potential. This systematic review assessed the current literature on blood biomarkers for identifying FGR infants at increased risk of adverse neurodevelopmental outcomes at >12 months after birth. Four databases were searched from inception to 22 February 2024. Articles were assessed for meeting the inclusion criteria by two reviewers. The quality of the included article was assessed using Quality Assessment of Diagnostic Accuracy Studies-2. A summary of findings is presented as insufficient articles were identified for meta-analysis. Excluding duplicates, 1,368 records were screened with only 9 articles considered for full text review. Only one article met all the inclusion criteria. Quality assessment indicated low risk of bias. Both blood biomarkers investigated in this study, neuron specific enolase and S100B, demonstrated inverse relationships with neurodevelopmental assessments at 2 years. Four studies did not meet all the inclusion criteria yet identified promising findings for metabolites and cytokines which are discussed here. These findings support the need for further research and highlight the potential for blood biomarkers to predict adverse outcomes.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=369242, Identifier CRD42022369242.

Early cognitive assessment in premature infants: the discriminatory value of eye-tracking vs. Bayley Scales

Introduction

The testing of visuocognitive development in preterm infants shows strong interactions between perinatal characteristics and cognition, learning and overall neurodevelopment evolution. The assessment of anticipatory gaze data of object-location bindings via eye-tracking can predict the neurodevelopment of preterm infants at the age of 3 years; little is known, however, about the early cognitive function and its assessment methods during the first year of life.

Methods

The current study presents data from a novel assessment tool, a Delayed Match Retrieval (DMR) paradigm via eye-tracking was used to measure visual working memory (VWM) and attention skills. The eye-tracking task that was designed to measure infants' ability to actively localize objects and to make online predictions of object-location bindings. 63 infants participated in the study, 39 preterm infants and 24 healthy full term infants - at a corrected age of 8-9 months for premature infants and similar chronological age for full term infants. Infants were also administered the Bayley Scales of Infant and Toddler Development.

Results

The analysis of the Bayley scores showed no significant difference between the two groups while the eye-tracking data showed a significant group effect on all measurements. Moreover, preterm infants' VWM performance was significantly lower than full term's. Birth weight affected the gaze time on all Areas Of Interest (AOIs), overall VWM performance and the scores at the Cognitive Bayley subscale. Furthermore, preterm infants with fetal growth restriction (FGR) showed significant performance effects in the eye-tracking measurements but not on their Bayley scores verifying the high discriminatory value of the eye gaze data.

Conclusion

Visual working memory and attention as measured via eye-tracking is a non-intrusive, painless, short duration procedure (approx. 4-min) was found to be a significant tool for identifying prematurity and FGR effects on the development of cognition during the first year of life. Bayley Scales alone may not pick up these deficits. Identifying tools for early neurodevelopmental assessments and cognitive function is important in order to enable earlier support and intervention in the vulnerable group of premature infants, given the associations between foundational executive functional skills and later cognitive and academic ability.

Acute-on-chronic: using magnetic resonance imaging to disentangle the haemodynamic responses to acute and chronic fetal hypoxaemia

Introduction

The fetal haemodynamic response to acute episodes of hypoxaemia are well characterised. However, how these responses change when the hypoxaemia becomes more chronic in nature such as that associated with fetal growth restriction (FGR), is less well understood. Herein, we utilised a combination of clinically relevant MRI techniques to comprehensively characterize and differentiate the haemodynamic responses occurring during acute and chronic periods of fetal hypoxaemia.

Methods

Prior to conception, carunclectomy surgery was performed on non-pregnant ewes to induce FGR. At 108-110 days (d) gestational age (GA), pregnant ewes bearing control (n = 12) and FGR (n = 9) fetuses underwent fetal catheterisation surgery. At 117-119 days GA, ewes underwent MRI sessions where phase-contrast (PC) and T2 oximetry were used to measure blood flow and oxygenation, respectively, throughout the fetal circulation during a normoxia and then an acute hypoxia state.

Results

Fetal oxygen delivery (DO2) was lower in FGR fetuses than controls during the normoxia state but cerebral DO2 remained similar between fetal groups. Acute hypoxia reduced both overall fetal and cerebral DO2. FGR increased ductus venosus (DV) and foramen ovale (FO) blood flow during both the normoxia and acute hypoxia states. Pulmonary blood flow (PBF) was lower in FGR fetuses during the normoxia state but similar to controls during the acute hypoxia state when PBF in controls was decreased.

Conclusion

Despite a prevailing level of chronic hypoxaemia, the FGR fetus upregulates the preferential streaming of oxygen-rich blood via the DV-FO pathway to maintain cerebral DO2. However, this upregulation is unable to maintain cerebral DO2 during further exposure to an acute episode of hypoxaemia. The haemodynamic alterations required at the level of the liver and lung to allow the DV-FO pathway to maintain cerebral DO2, may have lasting consequences on hepatic function and pulmonary vascular regulation after birth.

Is the sFlt-1/PlGF ratio efficient in predicting adverse neonatal outcomes in small-for-gestational-age newborns? A prospective observational multicenter cohort study

Introduction

Fetuses with growth abnormalities are at an increased risk of adverse neonatal outcomes. The aim of this study was to investigate if placental growth factor (PlGF), soluble fms-like tyrosine kinase-1 (sFlt-1), or the sFlt-1/PlGF ratio were efficient predictive factors of adverse neonatal outcomes in small-for-gestational-age (SGA) newborns.

Methods

A prospective observational multicenter cohort study was performed between 2020 and 2023. At the time of the SGA fetus diagnosis, serum angiogenic biomarker measurements were performed. The primary outcome was an adverse neonatal outcome, diagnosed in the case of any of the following: <34 weeks of gestation: mechanical ventilation, sepsis, necrotizing enterocolitis, intraventricular hemorrhage grade III or IV, and neonatal death before discharge; ≥34 weeks of gestation: Neonatal Intensive Care Unit hospitalization, mechanical ventilation, continuous positive airway pressure, sepsis, necrotizing enterocolitis, intraventricular hemorrhage grade III or IV, and neonatal death before discharge.

Results

In total, 192 women who delivered SGA newborns were included in the study. The serum concentrations of PlGF were lower, leading to a higher sFlt-1/PlGF ratio in the adverse outcome group. No significant differences in sFlt-1 levels were observed between the groups. Both PlGF and sFlt-1 had a moderate correlation with adverse neonatal outcomes (PlGF: R - 0.5, p < 0.001; sFlt-1: 0.5, p < 0.001). The sFlt-1/PlGF ratio showed a correlation of 0.6 (p < 0.001) with adverse outcomes. The uterine artery pulsatility index (PI) and the sFlt-1/PlGF ratio were identified as the only independent risk factors for adverse outcomes. An sFlt-1/PlGF ratio of 19.1 exhibited high sensitivity (85.1%) but low specificity (35.9%) in predicting adverse outcomes and had the strongest correlation with them. This ratio allowed the risk of adverse outcomes to be assessed as low with approximately 80% certainty.

Discussion

The sFlt-1/PlGF ratio seems to be an efficient predictive tool in adverse outcome risk assessment. More studies on large cohorts of SGA-complicated pregnancies with and without preeclampsia are needed to develop an optimal and detailed formula for the risk assessment of adverse outcomes in SGA newborns.

Mid-pregnancy placental transcriptome in a model of placental insufficiency with and without novel intervention

Fetal growth restriction (FGR) affects between 5-10% of all live births. Placental insufficiency is a leading cause of FGR, resulting in reduced nutrient and oxygen delivery to the fetus. Currently, there are no effective in utero treatment options for FGR, or placental insufficiency. We have developed a gene therapy to deliver, via a non-viral nanoparticle, human insulin-like 1 growth factor ( hIGF1 ) to the placenta as potential treatment of placenta insufficiency and FGR. Using a guinea pig maternal nutrient restriction (MNR) model of FGR, we aimed to understand the transcriptional changes within the placenta associated with placental insufficiency that occur prior to/at initiation of FGR, and the impact of short-term hIGF1 nanoparticle treatment. Using RNAsequencing, we analyzed protein coding genes of three experimental groups: Control and MNR dams receiving a sham treatment, and MNR dams receiving hIGF1 nanoparticle treatment. Pathway enrichment analysis comparing differentially expressed genelists in sham-treated MNR placentas to Control revealed upregulation of pathways associated with degradation and repair of genetic information and downregulation of pathways associated with transmembrane transport. When compared to sham-treated MNR placentas, MNR + hIGF1 placentas demonstrated changes to genelists associated with transmembrane transporter activity including ion, vitamin and solute carrier transport. Overall, this study identifies the key signaling and metabolic changes occurring in the placenta contributing to placental insufficiency prior to/at initiation of FGR, and increases our understanding of the pathways that our nanoparticle-mediated gene therapy intervention regulates.

Statements and Declarations

Competing Interests: Authors declare no conflicts of interest.

Fetal Growth Restriction Leads to an Enlarged Cup-to-Disc Ratio in Adults Born at Full Term

PURPOSE

This study explores associations between fetal growth restriction or excessive fetal growth, along with perinatal factors on the optic nerve head morphology in adulthood.

DESIGN

Retrospective cohort study.

METHODS

This retrospective cohort study involved a prospective ophthalmological examination of individuals born at full term (with a gestational age of ≥37 weeks) from 1969 to 2002. Each participant underwent nonmydriatic fundus camera photography to capture images of the optic discs, followed by manual measurements. The vertical cup-to-disc ratio (VCDR) and optic disc area were examined and analyzed in relation to the baby's birth weight relative to the gestational age. These categories included those with former moderate (birth weight percentile between the 3rd and <10th), severe SGA (below the third percentile), normal (AGA, 10th-90th percentile), and moderately (birth weight >90th-97th percentile) and severely (birth weight >97th percentile) large for gestational age (LGA) adults within the age range of 18 to 52 years.

RESULTS

Overall, 535 eyes of 280 individuals (age 29.7 ± 9.2 years, 144 females) born at full term were included. Multivariable analysis showed a significant association between a larger VCDR and the severe SGA group (B = 0.05, 95% CI 0.01-0.10; P = .02). In the univariable model, placental insufficiency was associated with VCDR (B = 0.10, 95% CI 0.01-0.19; P = .03). Other perinatal factors did not demonstrate an association with VCDR. Furthermore, there was an indication of an association suggesting a smaller optic disc area in individuals born moderately SGA at full term (B = -0.17, 95% CI -0.33 to -0.001; P = .05).

CONCLUSIONS

This study provides evidence that individuals born at-term with severe SGA have an increased VCDR, suggesting that fetal growth restriction has a lasting impact on optic disc morphology independent of prematurity throughout adulthood.

Perinatal compromise affects development, form, and function of the hippocampus part one; clinical studies

The hippocampus is a neuron-rich specialised brain structure that plays a central role in the regulation of emotions, learning and memory, cognition, spatial navigation, and motivational processes. In human fetal development, hippocampal neurogenesis is principally complete by mid-gestation, with subsequent maturation comprising dendritogenesis and synaptogenesis in the third trimester of pregnancy and infancy. Dendritogenesis and synaptogenesis underpin connectivity. Hippocampal development is exquisitely sensitive to perturbations during pregnancy and at birth. Clinical investigations demonstrate that preterm birth, fetal growth restriction (FGR), and acute hypoxic-ischaemic encephalopathy (HIE) are common perinatal complications that alter hippocampal development. In turn, deficits in hippocampal development and structure mediate a range of neurodevelopmental disorders, including cognitive and learning problems, autism, and Attention-Deficit/Hyperactivity Disorder (ADHD). In this review, we summarise the developmental profile of the hippocampus during fetal and neonatal life and examine the hippocampal deficits observed following common human pregnancy complications. IMPACT: The review provides a comprehensive summary of the developmental profile of the hippocampus in normal fetal and neonatal life. We address a significant knowledge gap in paediatric research by providing a comprehensive summary of the relationship between pregnancy complications and subsequent hippocampal damage, shedding new light on this critical aspect of early neurodevelopment.

Assessment of feto-placental oxygenation and perfusion in a rat model of placental insufficiency using T2* mapping and 3D dynamic contrast-enhanced MRI

INTRODUCTION

Placental insufficiency may lead to preeclampsia and fetal growth restriction. There is no cure for placental insufficiency, emphasizing the need for monitoring fetal and placenta health. Current monitoring methods are limited, underscoring the necessity for imaging techniques to evaluate fetal-placental perfusion and oxygenation. This study aims to use MRI to evaluate placental oxygenation and perfusion in the reduced uterine perfusion pressure (RUPP) model of placental insufficiency.

METHODS

Pregnant rats were randomized to RUPP (n = 11) or sham surgery (n = 8) on gestational day 14. On gestational day 19, rats imaged using a 7T MRI scanner to assess oxygenation and perfusion using T2* mapping and 3D-DCE MRI sequences, respectively. The effect of the RUPP on the feto-placental units were analyzed from the MRI images.

RESULTS

RUPP surgery led to reduced oxygenation in the labyrinth (24.7 ± 1.8 ms vs. 28.0 ± 2.1 ms, P = 0.002) and junctional zone (7.0 ± 0.9 ms vs. 8.1 ± 1.1 ms, P = 0.04) of the placenta, as indicated by decreased T2* values. However, here were no significant differences in fetal organ oxygenation or placental perfusion between RUPP and sham animals.

DISCUSSION

The reduced placental oxygenation without a corresponding decrease in perfusion suggests an adaptive response to placental ischemia. While acute reduction in placental perfusion may cause placental hypoxia, persistence of this condition could indicate chronic placental insufficiency after ischemic reperfusion injury. Thus, placental oxygenation may be a more reliable biomarker for assessing fetal condition than perfusion in hypertensive disorders of pregnancies including preeclampsia and FGR.

Understanding changes in echocardiographic parameters at different ages following fetal growth restriction: a systematic review and meta-analysis

Fetal growth restriction (FGR) increases cardiovascular risk by cardiac remodeling and programming. This systematic review and meta-analysis across species examines the use of echocardiography in FGR offspring at different ages. PubMed and Embase.com were searched for animal and human studies reporting on echocardiographic parameters in placental insufficiency-induced FGR offspring. We included six animal and 49 human studies. Although unable to perform a meta-analysis of animal studies because of insufficient number of studies per individual outcome, all studies showed left ventricular dysfunction. Our meta-analyses of human studies revealed a reduced left ventricular mass, interventricular septum thickness, mitral annular peak velocity, and mitral lateral early diastolic velocity at neonatal age. No echocardiographic differences during childhood were observed, although the small age range and number of studies limited these analyses. Only two studies at adult age were performed. Meta-regression on other influential factors was not possible due to underreporting. The few studies on myocardial strain analysis showed small changes in global longitudinal strain in FGR offspring. The quality of the human studies was considered low and the risk of bias in animal studies was mostly unclear. Echocardiography may offer a noninvasive tool to detect early signs of cardiovascular predisposition following FGR. Clinical implementation yet faces multiple challenges including identification of the most optimal timing and the exact relation to long-term cardiovascular function in which echocardiography alone might be limited to reflect a child's vascular status. Future research should focus on myocardial strain analysis and the combination of other (non)imaging techniques for an improved risk estimation.NEW & NOTEWORTHY Our meta-analysis revealed echocardiographic differences between fetal growth-restricted and control offspring in humans during the neonatal period: a reduced left ventricular mass and interventricular septum thickness, reduced mitral annular peak velocity, and mitral lateral early diastolic velocity. We were unable to pool echocardiographic parameters in animal studies and human adults because of an insufficient number of studies per individual outcome. The few studies on myocardial strain analysis showed small preclinical changes in FGR offspring.

Long-Term Neurologic Consequences following Fetal Growth Restriction: The Impact on Brain Reserve

BACKGROUND

Fetal growth restriction (FGR) corresponds to the fetus's inability to achieve an adequate weight gain based on genetic potential and gestational age. It is an important cause of morbidity and mortality.

SUMMARY

In this review, we address the challenges of diagnosis and classification of FGR. We review how chronic fetal hypoxia impacts brain development. We describe recent advances on placental and fetal brain imaging using magnetic resonance imaging and how they offer new noninvasive means to study growth restriction in humans. We go on to review the impact of FGR on brain integrity in the neonatal period, later childhood, and adulthood and review available therapies.

KEY MESSAGES

FGR consequences are not limited to the perinatal period. We hypothesize that impaired brain reserve, as defined by structure and size, may predict some concerning epidemiological data of impaired cognitive outcomes and dementia with aging in this group of patients.

Thyroid hormone analogues: Promising therapeutic avenues to improve the neurodevelopmental outcomes of intrauterine growth restriction

Intrauterine growth restriction (IUGR) is a pregnancy complication impairing fetal growth and development. The compromised development is often attributed to disruptions of oxygen and nutrient supply from the placenta, resulting in a number of unfavourable physiological outcomes with impaired brain and organ growth. IUGR is associated with compromised development of both grey and white matter, predisposing the infant to adverse neurodevelopmental outcomes, including long-lasting cognitive and motor difficulties. Cerebral thyroid hormone (TH) signalling, which plays a crucial role in regulating white and grey matter development, is dysregulated in IUGR, potentially contributing to the neurodevelopmental delays associated with this condition. Notably, one of the major TH transporters, monocarboxylate transporter-8 (MCT8), is deficient in the fetal IUGR brain. Currently, no effective treatment to prevent or reverse IUGR exists. Management strategies involve close antenatal monitoring, management of maternal risk factors if present and early delivery if IUGR is found to be severe or worsening in utero. The overall goal is to determine the most appropriate time for delivery, balancing the risks of preterm birth with further fetal compromise due to IUGR. Drug candidates have shown either adverse effects or little to no benefits in this vulnerable population, urging further preclinical and clinical investigation to establish effective therapies. In this review, we discuss the major neuropathology of IUGR driven by uteroplacental insufficiency and the concomitant long-term neurobehavioural impairments in individuals born IUGR. Importantly, we review the existing clinical and preclinical literature on cerebral TH signalling deficits, particularly the impaired expression of MCT8 and their correlation with IUGR. Lastly, we discuss the current evidence on MCT8-independent TH analogues which mimic the brain actions of THs by being metabolised in a similar manner as promising, albeit underappreciated approaches to promote grey and white matter development and improve the neurobehavioural outcomes following IUGR.

Morphologic development of the first-trimester utero-placental vasculature is positively associated with embryonic and fetal growth: the Rotterdam Periconception Cohort

STUDY QUESTION

Is morphologic development of the first-trimester utero-placental vasculature associated with embryonic growth and development, fetal growth, and birth weight percentiles?

SUMMARY ANSWER

Using the utero-placental vascular skeleton (uPVS) as a new imaging marker, this study reveals morphologic development of the first-trimester utero-placental vasculature is positively associated with embryonic growth and development, fetal growth, and birth weight percentiles.

WHAT IS KNOWN ALREADY

First-trimester development of the utero-placental vasculature is associated with placental function, which subsequently impacts embryonic and fetal ability to reach their full growth potential. The attribution of morphologic variations in the utero-placental vascular development, including the vascular structure and branching density, on prenatal growth remains unknown.

STUDY DESIGN, SIZE, DURATION

This study was conducted in the VIRTUAL Placental study, a subcohort of 214 ongoing pregnancies, embedded in the prospective observational Rotterdam Periconception Cohort (Predict study). Women were included before 10 weeks gestational age (GA) at a tertiary referral hospital in The Netherlands between January 2017 and March 2018.

PARTICIPANTS/MATERIALS, SETTING, METHODS

We obtained three-dimensional power Doppler volumes of the gestational sac including the embryo and the placenta at 7, 9, and 11 weeks of gestation. Virtual Reality-based segmentation and a recently developed skeletonization algorithm were applied to the power Doppler volumes to generate the uPVS and to measure utero-placental vascular volume (uPVV). Absolute vascular morphology was quantified by assigning a morphologic characteristic to each voxel in the uPVS (i.e. end-, bifurcation-crossing-, or vessel point). Additionally, total vascular length (mm) was calculated. The ratios of the uPVS characteristics to the uPVV were calculated to determine the density of vascular branching. Embryonic growth was estimated by crown-rump length and embryonic volume. Embryonic development was estimated by Carnegie stages. Fetal growth was measured by estimated fetal weight in the second and third trimester and birth weight percentiles. Linear mixed models were used to estimate trajectories of longitudinal measurements. Linear regression analysis with adjustments for confounders was used to evaluate associations between trajectories of the uPVS and prenatal growth. Groups were stratified for conception method (natural/IVF-ICSI conceptions), fetal sex (male/female), and the occurrence of placenta-related complications (yes/no).

MAIN RESULTS AND THE ROLE OF CHANCE

Increased absolute vascular morphologic development, estimated by positive random intercepts of the uPVS characteristics, is associated with increased embryonic growth, reflected by crown-rump length (endpoints β = 0.017, 95% CI [0.009; 0.025], bifurcation points β = 0.012, 95% CI [0.006; 0.018], crossing points β = 0.017, 95% CI [0.008; 0.025], vessel points β = 0.01, 95% CI [0.002; 0.008], and total vascular length β = 0.007, 95% CI [0.003; 0.010], and similarly with embryonic volume and Carnegie stage, all P-values ≤ 0.01. Density of vascular branching was negatively associated with estimated fetal weight in the third trimester (endpoints: uPVV β = -94.972, 95% CI [-185.245; -3.698], bifurcation points: uPVV β = -192.601 95% CI [-360.532; -24.670]) and birth weight percentiles (endpoints: uPVV β = -20.727, 95% CI [-32.771; -8.683], bifurcation points: uPVV β -51.097 95% CI [-72.257; -29.937], and crossing points: uPVV β = -48.604 95% CI [-74.246; -22.961])), all P-values < 0.05. After stratification, the associations were observed in natural conceptions specifically.

LIMITATION, REASONS FOR CAUTION

Although the results of this prospective observational study clearly demonstrate associations between first-trimester utero-placental vascular morphologic development and prenatal growth, further research is required before we can draw firm conclusions about a causal relationship.

WIDER IMPLICATIONS OF THE FINDINGS

Our findings support the hypothesis that morphologic variations in utero-placental vascular development play a role in the vascular mechanisms involved in embryonic and fetal growth and development. Application of the uPVS could benefit our understanding of the pathophysiology underlying placenta-related complications. Future research should focus on the clinical applicability of the uPVS as an imaging marker for the early detection of fetal growth restriction.

STUDY FUNDING/COMPETING INTEREST(S)

This research was funded by the Department of Obstetrics and Gynecology of the Erasmus MC, University Medical Centre, Rotterdam, The Netherlands. There are no conflicts of interest.

TRIAL REGISTRATION NUMBER

Registered at the Dutch Trial Register (NTR6854).

Neuroprotective effects of maternal melatonin administration in early-onset placental insufficiency and fetal growth restriction

BACKGROUND

Early-onset fetal growth restriction (FGR) is associated with adverse outcomes. We hypothesised that maternal melatonin administration will improve fetal brain structure in FGR.

METHODS

Surgery was performed on twin-bearing ewes at 88 days (0.6 gestation), and FGR induced in one twin via single umbilical artery ligation. Melatonin was administered intravenously (6 mg/day) to a group of ewes commencing on day of surgery until 127 days (0.85 gestation), when the ewe/fetuses were euthanized, and fetal brains collected.

RESULTS

Study groups were control (n = 5), FGR (n = 5), control+melatonin (control+MLT; n = 6) and FGR+melatonin (FGR + MLT; n = 6). Melatonin administration did not significantly alter fetal body or brain weights. Myelin (CNPase+) fibre density was reduced in FGR vs. control animals in most brain regions examined (p < 0.05) and melatonin treatment restored CNPase fibre density. Similar but less pronounced effect was seen with mature myelin (MBP+) staining. Significant differences in activated microglia (Iba-1) activity were seen between lamb groups (MLT mitigated FGR effect) in periventricular white matter, subventricular zone and external capsule (p < 0.05). Similar effects were seen in astrogliosis (GFAP) in intragyral white matter and cortex.

CONCLUSIONS

Maternal melatonin administration in early onset FGR led to improved myelination of white matter brain regions, possibly mediated by decreased inflammation.

IMPACT

Maternal melatonin administration might lead to neuroprotection in the growth-restricted fetus, possibly via dampening neuroinflammation and enhancing myelination. This preclinical study adds to the body of work on this topic, and informs clinical translation. Neuroprotection likely to improve long-term outcomes of this vulnerable infant group.

Leptin deficiency, a potential mechanism for impaired fetal lung development in uteroplacental insufficiency?

Uteroplacental insufficiency (UPI) is a major cause of fetal growth restriction (FGR). Leptin, an adipokine, has been shown to play a vital role in fetal organogenesis. There is evidence reporting leptin deficiency in preterm and growth-restricted fetuses. In this issue of Pediatric Research, Yuliana et al. report leptin expression and lung development in UPI-induced FGR rats. UPI-induced FGR rats expressed decreased lung leptin and had impaired lung development, as shown by decreased surface area and lung volume. They also found a significant association between lung radial alveolar count, serum leptin, von Willebrand factor, and specific metabolites on metabolomic analyses. Previous studies on leptin supplementation in vivo have been associated with improvement in lung maturation; supporting the evidence, that leptin improves lung growth and development in FGR and may have future therapeutic potential in the improvement of respiratory outcomes in these infants. Future studies to support evidence of this association in humans are warranted.

Vaginal micronised progesterone for the prevention of hypertensive disorders of pregnancy: A systematic review and meta-analysis

BACKGROUND

Treatment with vaginal progesterone reduces the risk of miscarriage and preterm birth in selected high-risk women. The hypothesis that vaginal progesterone can reduce the risk of hypertensive disorders of pregnancy (HDP) is unexplored.

OBJECTIVES

To summarise the evidence on the effectiveness of vaginal progesterone to reduce the risk of HDP.

SEARCH STRATEGY

We searched Embase (OVID), MEDLINE (OVID), PubMed, CENTRAL and clinicaltrials.gov from inception until 20 June 2023.

SELECTION CRITERIA

We included placebo-controlled randomised trials (RCTs) of vaginal progesterone for the prevention or treatment of any pregnancy complications.

DATA COLLECTION AND ANALYSIS

We extracted absolute event numbers for HDP and pre-eclampsia in women receiving vaginal progesterone or placebo, and meta-analysed the data with a random effects model. We appraised the certainty of the evidence using GRADE methodology.

MAIN RESULTS

The quantitative synthesis included 11 RCTs, of which three initiated vaginal progesterone in the first trimester, and eight in the second or third trimesters. Vaginal progesterone started in the first trimester of pregnancy lowered the risk of any HDP (risk ratio [RR] 0.71, 95% confidence interval [CI] 0.53-0.93, 2 RCTs, n = 4431 women, I2 = 0%; moderate-certainty evidence) and pre-eclampsia (RR 0.61, 95% CI 0.41-0.92, 3 RCTs, n = 5267 women, I2 = 0%; moderate-certainty evidence) when compared with placebo. Vaginal progesterone started in the second or third trimesters was not associated with a reduction in HDP (RR 1.19, 95% CI 0.67-2.12, 3 RCTs, n = 1602 women, I2 = 9%; low-certainty evidence) or pre-eclampsia (RR 0.97, 95% CI 0.71-1.31, 5 RCTs, n = 4274 women, I2 = 0%; low-certainty evidence).

CONCLUSIONS

Our systematic review found first-trimester initiated vaginal micronised progesterone may reduce the risk of HDP and pre-eclampsia.

Placenta: an old organ with new functions

The transition from oviparity to viviparity and the establishment of feto-maternal communications introduced the placenta as the major anatomical site to provide nutrients, gases, and hormones to the developing fetus. The placenta has endocrine functions, orchestrates maternal adaptations to pregnancy at different periods of pregnancy, and acts as a selective barrier to minimize exposure of developing fetus to xenobiotics, pathogens, and parasites. Despite the fact that this ancient organ is central for establishment of a normal pregnancy in eutherians, the placenta remains one of the least studied organs. The first step of pregnancy, embryo implantation, is finely regulated by the trophoectoderm, the precursor of all trophoblast cells. There is a bidirectional communication between placenta and endometrium leading to decidualization, a critical step for maintenance of pregnancy. There are three-direction interactions between the placenta, maternal immune cells, and the endometrium for adaptation of endometrial immune system to the allogeneic fetus. While 65% of all systemically expressed human proteins have been found in the placenta tissues, it expresses numerous placenta-specific proteins, whose expression are dramatically changed in gestational diseases and could serve as biomarkers for early detection of gestational diseases. Surprisingly, placentation and carcinogenesis exhibit numerous shared features in metabolism and cell behavior, proteins and molecular signatures, signaling pathways, and tissue microenvironment, which proposes the concept of "cancer as ectopic trophoblastic cells". By extensive researches in this novel field, a handful of cancer biomarkers has been discovered. This review paper, which has been inspired in part by our extensive experiences during the past couple of years, highlights new aspects of placental functions with emphasis on its immunomodulatory role in establishment of a successful pregnancy and on a potential link between placentation and carcinogenesis.

The associations between maternal and fetal exposure to endocrine-disrupting chemicals and asymmetric fetal growth restriction: a prospective cohort study

Recent evidence has revealed associations between endocrine-disrupting chemicals (EDCs) and placental insufficiency due to altered placental growth, syncytialization, and trophoblast invasion. However, no epidemiologic study has reported associations between exposure to EDCs and asymmetric fetal growth restriction (FGR) caused by placenta insufficiency. The aim of this study was to evaluate the association between EDC exposure and asymmetric FGR. This was a prospective cohort study including women admitted for delivery to the Maternal Fetal Center at Seoul St. Mary's Hospital between October 2021 and October 2022. Maternal urine and cord blood samples were collected, and the levels of bisphenol-A (BPA), monoethyl phthalates, and perfluorooctanoic acid in each specimen were analyzed. We investigated linear and non-linear associations between the levels of EDCs and fetal growth parameters, including the head circumference (HC)/abdominal circumference (AC) ratio as an asymmetric parameter. The levels of EDCs were compared between fetuses with and without asymmetric FGR. Of the EDCs, only the fetal levels of BPA showed a linear association with the HC/AC ratio after adjusting for confounding variables (β = 0.003, p < 0.05). When comparing the normal growth and asymmetric FGR groups, the asymmetric FGR group showed significantly higher maternal and fetal BPA levels compared to the normal growth group (maternal urine BPA, 3.99 μg/g creatinine vs. 1.71 μg/g creatinine [p < 0.05]; cord blood BPA, 1.96 μg/L vs. -0.86 μg/L [p < 0.05]). In conclusion, fetal exposure levels of BPA show linear associations with asymmetric fetal growth patterns. High maternal and fetal exposure to BPA might be associated with asymmetric FGR.

Placental Nanoparticle-mediated IGF1 Gene Therapy Corrects Fetal Growth Restriction in a Guinea Pig Model

Fetal growth restriction (FGR) caused by placental insufficiency is a major contributor to neonatal morbidity and mortality. There is currently no in utero treatment for placental insufficiency or FGR. The placenta serves as the vital communication, supply, exchange, and defense organ for the developing fetus and offers an excellent opportunity for therapeutic interventions. Here we show efficacy of repeated treatments of trophoblast-specific human insulin-like 1 growth factor ( IGF1 ) gene therapy delivered in a non-viral, polymer nanoparticle to the placenta for the treatment of FGR. Using the guinea pig maternal nutrient restriction model of FGR, nanoparticle-mediated IGF1 treatment was delivered to the placenta via ultrasound guidance across the second half of pregnancy, after establishment of FGR. This treatment resulted in correction of fetal weight in MNR animals compared to control, improved fetal physiology and no negative maternal side-effects. Overall, we show for the first time a therapy capable of improving the entire pregnancy environment: maternal, placental, and fetal. This combined with our previous studies using this therapy at both mid pregnancy and in numerous cell and animal models demonstrate the plausibility of this therapy for future human translation to improve health outcomes of neonates and decrease numerous morbidities associated with the developmental origins of disease.

Obesogenic Diet in Mice Leads to Inflammation and Oxidative Stress in the Mother in Association with Sex-Specific Changes in Fetal Development, Inflammatory Markers and Placental Transcriptome

BACKGROUND

Obesity during pregnancy is related to adverse maternal and neonatal outcomes. Factors involved in these outcomes may include increased maternal insulin resistance, inflammation, oxidative stress, and nutrient mishandling. The placenta is the primary determinant of fetal outcomes, and its function can be impacted by maternal obesity. The aim of this study on mice was to determine the effect of obesity on maternal lipid handling, inflammatory and redox state, and placental oxidative stress, inflammatory signaling, and gene expression relative to female and male fetal growth.

METHODS

Female mice were fed control or obesogenic high-fat/high-sugar diet (HFHS) from 9 weeks prior to, and during, pregnancy. On day 18.5 of pregnancy, maternal plasma, and liver, placenta, and fetal serum were collected to examine the immune and redox states. The placental labyrinth zone (Lz) was dissected for RNA-sequencing analysis of gene expression changes.

RESULTS

the HFHS diet induced, in the dams, hepatic steatosis, oxidative stress (reduced catalase, elevated protein oxidation) and the activation of pro-inflammatory pathways (p38-MAPK), along with imbalanced circulating cytokine concentrations (increased IL-6 and decreased IL-5 and IL-17A). HFHS fetuses were asymmetrically growth-restricted, showing sex-specific changes in circulating cytokines (GM-CSF, TNF-α, IL-6 and IFN-γ). The morphology of the placenta Lz was modified by an HFHS diet, in association with sex-specific alterations in the expression of genes and proteins implicated in oxidative stress, inflammation, and stress signaling. Placental gene expression changes were comparable to that seen in models of intrauterine inflammation and were related to a transcriptional network involving transcription factors, LYL1 and PLAG1.

CONCLUSION

This study shows that fetal growth restriction with maternal obesity is related to elevated oxidative stress, inflammatory pathways, and sex-specific placental changes. Our data are important, given the marked consequences and the rising rates of obesity worldwide.

Early-life influenza A (H1N1) infection independently programs brain connectivity, HPA AXIS and tissue-specific gene expression profiles

Early-life adversity covers a range of physical, social and environmental stressors. Acute viral infections in early life are a major source of such adversity and have been associated with a broad spectrum of later-life effects outside the immune system or "off-target". These include an altered hypothalamus-pituitary-adrenal (HPA) axis and metabolic reactions. Here, we used a murine post-natal day 14 (PND 14) Influenza A (H1N1) infection model and applied a semi-holistic approach including phenotypic measurements, gene expression arrays and diffusion neuroimaging techniques to investigate HPA axis dysregulation, energy metabolism and brain connectivity. By PND 56 the H1N1 infection had been resolved, and there was no residual gene expression signature of immune cell infiltration into the liver, adrenal gland or brain tissues examined nor of immune-related signalling. A resolved early-life H1N1 infection had sex-specific effects. We observed retarded growth of males and altered pre-stress (baseline) blood glucose and corticosterone levels at PND42 after the infection was resolved. Cerebral MRI scans identified reduced connectivity in the cortex, midbrain and cerebellum that were accompanied by tissue-specific gene expression signatures. Gene set enrichment analysis confirmed that these were tissue-specific changes with few common pathways. Early-life infection independently affected each of the systems and this was independent of HPA axis or immune perturbations.

Fetal growth restriction exhibits various mTOR signaling in different regions of mouse placentas with altered lipid metabolism

Fetal growth restriction (FGR) is a common complication of pregnancy and can have significant impact on obstetric and neonatal outcomes. Increasing evidence has shown that the inhibited mechanistic target of rapamycin (mTOR) signaling in placenta is associated with FGR. However, interpretation of existing research is limited due to inconsistent methodologies and varying understanding of the mechanism by which mTOR activity contributes to FGR. Hereby, we have demonstrated that different anatomic regions of human and mouse placentas exhibited different levels of mTOR activity in normal compared to FGR pregnancies. When using the rapamycin-induced FGR mouse model, we found that placentas of FGR pregnancies exhibited abnormal morphological changes and reduced mTOR activity in the decidual-junctional layer. Using transcriptomics and lipidomics, we revealed that lipid and energy metabolism was significantly disrupted in the placentas of FGR mice. Finally, we demonstrated that maternal physical exercise during gestation in our FGR mouse model was associated with increased fetal and placental weight as well as increased placental mTOR activity and lipid metabolism. Collectively, our data indicate that the inhibited placental mTOR signaling contributes to FGR with altered lipid metabolism in mouse placentas, and maternal exercise could be an effective method to reduce the occurrence of FGR or alleviate the adverse outcomes associated with FGR.

Etiology, Diagnosis and Management of Persistent Pulmonary Hypertension of the Newborn in Resource-limited Settings

Persistent Pulmonary Hypertension of the Newborn (PPHN) is more common in Low and middle income countries (LMICs) due to high incidence of sepsis, perinatal asphyxia and meconium aspiration syndrome. Presence of hypoxic respiratory faillure and greater than 5% difference in preductal and post ductal saturation increases clinical sucipision for PPHN. The availability of Inhaled nitric oxide and extracorporaeal membrane oxygenation is limited but pulmonary vasodilators such as sildenafil are readily available in most LMICs.

Early Fetal Growth Restriction with or Without Hypertensive Disorders: a Clinical Overview

Early onset fetal growth restriction (FGR) is one of the main adverse pregnancy conditions, often associated with poor neonatal outcomes. Frequently, early onset FGR is associated with early onset hypertensive disorders of pregnancy (HDP), and in particular preeclampsia (PE). However, to date, it is still an open question whether pregnancies complicated by early FGR plus HDP (FGR-HDP) and those complicated by early onset FGR without HDP (normotensive-FGR (n-FGR)) show different prenatal and postnatal outcomes and, consequently, should benefit from different management and long-term follow-up. Recent data support the hypothesis that the presence of PE may have an additional impact on maternal hemodynamic impairment and placental lesions, increasing the risk of poor neonatal outcomes in pregnancy affected by early onset FGR-HDP compared to pregnancy affected by early onset n-FGR. This review aims to elucidate this poor studied topic, comparing the clinical characteristics, perinatal outcomes, and potential long-term sequelae of early onset FGR-HDP and early onset n-FGR.

Maternal Age at Menarche Genes Determines Fetal Growth Restriction Risk

We aimed to explore the potential link of maternal age at menarche (mAAM) gene polymorphisms with risk of the fetal growth restriction (FGR). This case (FGR)-control (FGR free) study included 904 women (273 FGR and 631 control) in the third trimester of gestation examined/treated in the Departments of Obstetrics. For single nucleotide polymorphism (SNP) multiplex genotyping, 50 candidate loci of mAAM were chosen. The relationship of mAAM SNPs and FGR was appreciated by regression procedures (logistic/model-based multifactor dimensionality reduction [MB-MDR]) with subsequent in silico assessment of the assumed functionality pithy of FGR-related loci. Three mAAM-appertain loci were FGR-linked to genes such as KISS1 (rs7538038) (effect allele G-odds ratio (OR)allelic = 0.63/pperm = 0.0003; ORadditive = 0.61/pperm = 0.001; ORdominant = 0.56/pperm = 0.001), NKX2-1 (rs999460) (effect allele A-ORallelic = 1.37/pperm = 0.003; ORadditive = 1.45/pperm = 0.002; ORrecessive = 2.41/pperm = 0.0002), GPRC5B (rs12444979) (effect allele T-ORallelic = 1.67/pperm = 0.0003; ORdominant = 1.59/pperm = 0.011; ORadditive = 1.56/pperm = 0.009). The haplotype ACA FSHB gene (rs555621*rs11031010*rs1782507) was FRG-correlated (OR = 0.71/pperm = 0.05). Ten FGR-implicated interworking models were founded for 13 SNPs (pperm ≤ 0.001). The rs999460 NKX2-1 and rs12444979 GPRC5B interplays significantly influenced the FGR risk (these SNPs were present in 50% of models). FGR-related mAAM-appertain 15 polymorphic variants and 350 linked SNPs were functionally momentous in relation to 39 genes participating in the regulation of hormone levels, the ovulation cycle process, male gonad development and vitamin D metabolism. Thus, this study showed, for the first time, that the mAAM-appertain genes determine FGR risk.

Preconception maternal gastric bypass surgery and the impact on fetal growth parameters

BACKGROUND

Bariatric surgery is increasingly performed in women of reproductive age. As bariatric surgery will result in postoperative rapid catabolic weight loss which potentially leads to fetal malnutrition and directly related impaired intra-uterine growth, it is advised to postpone pregnancy for at least 12-18 months after surgery.

OBJECTIVES

To investigate the consequences of preconception gastric bypass surgery (pGB) on fetal growth parameters and maternal pregnancy outcome.

SETTING

Maasstad Hospital, The Netherlands, general hospital and Erasmus Medical Center, The Netherlands, university hospital.

METHODS

We included 97 pGB pregnancies (Maasstad hospital) and 440 non-bariatric pregnancies (Rotterdam Periconception cohort, Erasmus Medical Center). Longitudinal second and third trimester fetal growth parameters (head circumference, biparietal diameter, femur length, abdominal circumference, estimated fetal weight) were analyzed using linear mixed models, adjusting for covariates and possible confounders. Fetal growth and birthweight in pGB pregnancies were compared to non-bariatric pregnancies and Dutch reference curves. Maternal pregnancy outcome in the pGB group was compared to non-bariatric pregnancies.

RESULTS

All fetal growth parameters of pGB pregnancies were significantly decreased at 20 weeks' gestation (P < .001) and throughout the remaining part of pregnancy (P < .05) compared with non-bariatric pregnancies (crude and adjusted models). In our cohort, gestational weight gain was not significantly associated with birthweight corrected for gestational age. Birthweight was significantly lower in pGB pregnancies (estimate -241 grams [95% CI, -342.7 to -140.0]) with a 2-fold increased risk of small-for-gestational-age (SGA) (adjusted odds ratio 2.053 [95% CI, 1.058 to 3.872]). Compared to the non-bariatric pregnancies, we found no significant differences in maternal pregnancy outcome.

CONCLUSIONS

PGB is associated with overall reduced fetal growth trajectories and a 2-fold increased risk of SGA, without significant adverse consequences for maternal pregnancy outcome. We recommend close monitoring of fetal growth after pGB.

Metabolic and fecal microbial changes in adult fetal growth restricted mice

BACKGROUND

Fetal growth restriction (FGR) increases risk for development of obesity and type 2 diabetes. Using a mouse model of FGR, we tested whether metabolic outcomes were exacerbated by high-fat diet challenge or associated with fecal microbial taxa.

METHODS

FGR was induced by maternal calorie restriction from gestation day 9 to 19. Control and FGR offspring were weaned to control (CON) or 45% fat diet (HFD). At age 16 weeks, offspring underwent intraperitoneal glucose tolerance testing, quantitative MRI body composition assessment, and energy balance studies. Total microbial DNA was used for amplification of the V4 variable region of the 16 S rRNA gene. Multivariable associations between groups and genera abundance were assessed using MaAsLin2.

RESULTS

Adult male FGR mice fed HFD gained weight faster and had impaired glucose tolerance compared to control HFD males, without differences among females. Irrespective of weaning diet, adult FGR males had depletion of Akkermansia, a mucin-residing genus known to be associated with weight gain and glucose handling. FGR females had diminished Bifidobacterium. Metabolic changes in FGR offspring were associated with persistent gut microbial changes.

CONCLUSION

FGR results in persistent gut microbial dysbiosis that may be a therapeutic target to improve metabolic outcomes.

IMPACT

Fetal growth restriction increases risk for metabolic syndrome later in life, especially if followed by rapid postnatal weight gain. We report that a high fat diet impacts weight and glucose handling in a mouse model of fetal growth restriction in a sexually dimorphic manner. Adult growth-restricted offspring had persistent changes in fecal microbial taxa known to be associated with weight, glucose homeostasis, and bile acid metabolism, particularly Akkermansia, Bilophilia and Bifidobacteria. The gut microbiome may represent a therapeutic target to improve long-term metabolic outcomes related to fetal growth restriction.

Navigating the path of TOF- A Literature review unveiling maternal-fetal dynamics, treatment strategies and psychological dimensions

Tetralogy of Fallot (TOF) is a complex congenital heart defect that poses unique challenges for both mothers and their unborn children. This comprehensive review, aims to provide a holistic exploration of the maternal-fetal dynamics, treatment strategies, and psychological dimensions involved in navigating the path of TOF during pregnancy. It delves into the physiological changes that occur during pregnancy in TOF patients, including pulmonary regurgitation, right ventricular hypertrophy, and the overriding aorta. By understanding these dynamics, healthcare professionals can tailor treatment strategies to optimize maternal and fetal outcomes. The review further investigates the treatment strategies employed in managing TOF during pregnancy, encompassing medical interventions, cardiac monitoring, and multidisciplinary care. It explores the role of advanced imaging techniques, such as echocardiography and cardiac magnetic resonance imaging, in assessing TOF severity and guiding treatment decisions. The psychological factors influencing maternal adaptation, coping strategies, and the long-term implications on the child's psychological development are also examined. The integration of multidisciplinary approaches, including cardiac care, psychosocial support, and mental health interventions, can orchestrate a harmonious symphony of maternal-fetal well-being in the challenging journey of TOF pregnancies. Future research endeavours should continue to explore these dimensions, further refining treatment strategies and enhancing the understanding of TOF pregnancies for improved outcomes.

Trophectoderm biopsy of blastocysts following IVF and embryo culture increases epigenetic dysregulation in a mouse model

STUDY QUESTION

Does trophectoderm biopsy (TEBx) of blastocysts for preimplantation genetic testing in the clinic affect normal placental and embryo development and offspring metabolic outcomes in a mouse model?

SUMMARY ANSWER

TEBx impacts placental and embryonic health during early development, with some alterations resolving and others worsening later in development and triggering metabolic changes in adult offspring.

WHAT IS KNOWN ALREADY

Previous studies have not assessed the epigenetic and morphological impacts of TEBx either in human populations or in animal models.

STUDY DESIGN, SIZE, DURATION

We employed a mouse model to identify the effects of TEBx during IVF. Three groups were assessed: naturally conceived (Naturals), IVF, and IVF + TEBx, at two developmental timepoints: embryonic day (E)12.5 (n = 40/Naturals, n = 36/IVF, and n = 36/IVF + TEBx) and E18.5 (n = 42/Naturals, n = 30/IVF, and n = 35/IVF + TEBx). Additionally, to mimic clinical practice, we assessed a fourth group: IVF + TEBx + Vitrification (Vit) at E12.5 (n = 29) that combines TEBx and vitrification. To assess the effect of TEBx in offspring health, we characterized a 12-week-old cohort (n = 24/Naturals, n = 25/IVF and n = 25/IVF + TEBx).

PARTICIPANTS/MATERIALS, SETTING, METHODS

Our mouse model used CF-1 females as egg donors and SJL/B6 males as sperm donors. IVF, TEBx, and vitrification were performed using standardized methods. Placenta morphology was evaluated by hematoxylin-eosin staining, in situ hybridization using Tpbpa as a junctional zone marker and immunohistochemistry using CD34 fetal endothelial cell markers. For molecular analysis of placentas and embryos, DNA methylation was analyzed using pyrosequencing, luminometric methylation assay, and chip array technology. Expression patterns were ascertained by RNA sequencing. Triglycerides, total cholesterol, high-, low-, and very low-density lipoprotein, insulin, and glucose were determined in the 12-week-old cohort using commercially available kits.

MAIN RESULTS AND THE ROLE OF CHANCE

We observed that at E12.5, IVF + TEBx had a worse outcome in terms of changes in DNA methylation and differential gene expression in placentas and whole embryos compared with IVF alone and compared with Naturals. These changes were reflected in alterations in placental morphology and blood vessel density. At E18.5, early molecular changes in fetuses were maintained or exacerbated. With respect to placentas, the molecular and morphological changes, although different compared to Naturals, were equivalent to the IVF group, except for changes in blood vessel density, which persisted. Of note is that most differences were sex specific. We conclude that TEBx has more detrimental effects in mid-gestation placental and embryonic tissues, with alterations in embryonic tissues persisting or worsening in later developmental stages compared to IVF alone, and the addition of vitrification after TEBx results in more pronounced and potentially detrimental epigenetic effects: these changes are significantly different compared to Naturals. Finally, we observed that 12-week IVF + TEBx offspring, regardless of sex, showed higher glucose, insulin, triglycerides, lower total cholesterol, and lower high-density lipoprotein compared to IVF and Naturals, with only males having higher body weight compared to IVF and Naturals. Our findings in a mouse model additionally support the need for more studies to assess the impact of new procedures in ART to ensure healthy pregnancies and offspring outcomes.

LARGE SCALE DATA

Data reported in this work have been deposited in the NCBI Gene Expression Omnibus under accession number GSE225318.

LIMITATIONS, REASONS FOR CAUTION

This study was performed using a mouse model that mimics many clinical IVF procedures and outcomes observed in humans, where studies on early embryos are not possible.

WIDER IMPLICATIONS OF THE FINDINGS

This study highlights the importance of assaying new procedures used in ART to assess their impact on placenta and embryo development, and offspring metabolic outcomes.

STUDY FUNDING/COMPETING INTEREST(S)

This work was funded by a National Centers for Translational Research in Reproduction and Infertility grant P50 HD068157-06A1 (M.S.B., C.C., M.M.), Ruth L. Kirschstein National Service Award Individual Postdoctoral Fellowship F32 HD107914 (E.A.R.-C.) and F32 HD089623 (L.A.V.), and National Institutes of Health Training program in Cell and Molecular Biology T32 GM007229 (C.N.H.). No conflict of interest.

Effects of fetal growth restriction on the perinatal neurovascular unit and possible treatment targets

The neurovascular unit (NVU) within the brain is a multicellular unit that synergistically acts to maintain blood-brain barrier function and meet cerebral metabolic demand. Recent studies have indicated disruption to the NVU is associated with neuropathology in the perinatal brain. Infants with fetal growth restriction (FGR) are known to be at increased risk of neurodevelopmental conditions including motor, learning, and behavioural deficits. There are currently no neuroprotective treatments for these conditions. In this review, we analyse large animal studies examining the effects of FGR on the perinatal NVU. These studies show altered vascularity in the FGR brain as well as blood-brain barrier dysfunction due to underlying cellular changes, mediated by neuroinflammation. Neuroinflammation is a key mechanism associated with pathological effects in the FGR brain. Hence, targeting inflammation may be key to preserving the multicellular NVU and providing neuroprotection in FGR. A number of maternal and postnatal therapies with anti-inflammatory components have been investigated in FGR animal models examining targets for amelioration of NVU disruption. Each therapy showed promise by uniquely ameliorating the adverse effects of FGR on multiple aspects of the NVU. The successful implementation of a clinically viable neuroprotective treatment has the potential to improve outcomes for neonates affected by FGR. IMPACT: Disruption to the neurovascular unit is associated with neuropathology in fetal growth restriction. Inflammation is a key mechanism associated with neurovascular unit disruption in the growth-restricted brain. Anti-inflammatory treatments ameliorate adverse effects on the neurovascular unit and may provide neuroprotection.

Liposome-Encapsulated Anti-inflammatory Proteins for Targeted Delivery to the Placenta to Treat Fetal Growth Restriction

Fetal growth restriction (FGR), the failure of a fetus to reach its genetically determined growth potential, is a serious complication affecting up to 10% of pregnancies. FGR is a major risk factor for stillbirth and, in the survivors, neurodevelopmental disorders. We have recently identified that the anti-inflammatory and pro-resolving molecule, lipoxin A4 (LXA4) and its soluble receptor, formyl-peptide receptor-2 (FPR-2) are significantly decreased in human placentas from FGR pregnancy. The LXA4 synthetic analog Compound 43 (C43) is considered a safe, anti-inflammatory therapy and is being developed as a treatment for disease conditions with an inflammatory basis, for example, asthma in children. Identification of therapies to treat FGR in utero comes with the need to mitigate their potential side effects and the use of nanoparticle-mediated delivery systems could facilitate this. Our current studies are focused on targeting the resolution of inflammation observed in FGR placentas, by synthesizing liposome-encapsulated C43 as a novel therapeutic to improve placental function in FGR. In this chapter, we provide a detailed methodological procedure for the preparation of liposomes and conjugation of the peptide sequences, which selectively bind to the outer placental syncytiotrophoblast layer or the vascular endothelium of the uterine spiral arterioles.

Fetal growth restriction: How reliable is information available to patients on Google? A systematic review

OBJECTIVES

To review systematically the quality, readability and credibility of English language webpages offering patient information on fetal growth restriction.

STUDY DESIGN

A systematic review of patient information was undertaken on Google with location services and browser history disabled. Websites from the first page were included providing they gave at least 300 words of health information on fetal growth restriction aimed at patients. Validated assessment of readability, credibility and quality were undertaken. An accuracy assessment was performed based on international guidance. Characteristics were tabulated.

RESULTS

Thirty-one websites including 30 different texts were included. No pages had a reading age of 11 years or less, none were credible, and only one was of high quality. Median accuracy rating was 9/24.

CONCLUSION

Patients cannot rely on Google as a source of information on fetal growth restriction. As well as being difficult to read, information tends to be low quality, low accuracy and not credible. Healthcare professionals must consider how to enable access to high-quality patient information and give time for discussion of information patients have found: failure to do so may disenfranchise patients.

Valproic acid elevates HIF-1α-mediated CGB expression and suppresses glucose uptake in BeWo cells

Placental dysfunction can disrupt pregnancy. However, few studies have assessed the effects of chemical-induced toxicity on placental function. Here, we examined the effects of valproic acid (VPA) as a model chemical on production of hormones and on glucose uptake in human choriocarcinoma cell line BeWo. Cells were treated with forskolin to differentiate into syncytiotrophoblasts, which were then treated with VPA for 72 hr. Real-time RT-PCR analysis showed that VPA significantly increased the mRNA expression of chorionic gonadotropin β (CGB), a hormone that is produced by the placenta in the first trimester of pregnancy, relative to that in the forskolin-only group. It also suppressed the increase in intracellular glucose uptake and GLUT1 level observed in the forskolin-only group. RNA-seq analysis and pathway database analysis revealed that VPA consistently decreased the level of HIF-1α protein and expression of its downstream target genes HK2 and ADM in the hypoxia pathway. Cobalt chloride, a HIF-1α inducer, inhibited CGB upregulation in VPA-treated cells and rescued VPA-induced suppression of glucose uptake and GLUT1 level. Thus, HIF-1α-mediated elevation of CGB expression and suppression of glucose uptake by VPA is a novel mechanism of placental dysfunction.

Cardiovascular decline in offspring during the perinatal period in an ovine model of fetal growth restriction

Fetal growth restriction (FGR) increases the risk cardiovascular disease (CVD) in adulthood. Placental insufficiency and subsequent chronic fetal hypoxemia are causal factors for FGR, leading to a redistribution of blood flow that prioritizes vital organs. Subclinical signs of cardiovascular dysfunction are evident in growth-restricted neonates; however, the mechanisms programming for CVD in adulthood remain unknown. This study aimed to determine the potential mechanisms underlying structural and functional changes within the heart and essential (carotid) and nonessential (femoral) vascular beds in growth-restricted lambs. Placental insufficiency was surgically induced in ewes at 89 days gestational age (dGA, term = 148dGA). Three age groups were investigated: fetal (126dGA), newborn (24 h after preterm birth), and 4-wk-old lambs. In vivo and histological assessments of cardiovascular indices were undertaken. Resistance femoral artery function was assessed via in vitro wire myography and blockade of key vasoactive pathways including nitric oxide, prostanoids, and endothelium-dependent hyperpolarization. All lambs were normotensive throughout the first 4 wk of life. Overall, the FGR cohort had more globular hearts compared with controls (P = 0.0374). A progressive decline in endothelium-dependent vasodilation was demonstrated in FGR lambs compared with controls. Further investigation revealed that impairment of the prostanoid pathway may drive this reduction in vasodilatory capacity. Clinical indicators of CVD were not observed in our FGR lambs. However, subclinical signs of cardiovascular dysfunction were present in our FGR offspring. This study provides insight into potential mechanisms, such as the prostanoid pathway, that may warrant therapeutic interventions to improve cardiovascular development in growth-restricted newborns.NEW & NOTEWORTHY Our findings provide novel insight into the potential mechanisms that program for cardiovascular dysfunction in growth-restricted neonates as our growth-restricted lambs exhibited a progressive decline in endothelium-dependent vasodilation in the femoral artery between birth and 4 wk of age. Subsequent analyses indicated that this reduction in vasodilatory capacity is likely to be mediated by the prostanoid pathway and prostanoids could be a potential target for therapeutic interventions for fetal growth restriction (FGR).

Adults are just big kids: pediatric considerations for adult critical care nephrology

PURPOSE OF REVIEW

In recent years, there has been growing attention to pediatric kidney health, especially pediatric acute kidney injury (AKI). However, there has been limited focus on the role of pediatric AKI on adult kidney health, specifically considerations for the critical care physician.

RECENT FINDINGS

We summarize what is known in the field of pediatric AKI to inform adult medical care including factors throughout the early life course, including perinatal, neonatal, and pediatric exposures that impact survivor care later in adulthood.

SUMMARY

The number of pediatric AKI survivors continues to increase, leading to a higher burden of chronic kidney disease and other long-term co-morbidities later in life. Adult medical providers should consider pediatric history and illnesses to inform the care they provide. Such knowledge may help internists, nephrologists, and intensivists alike to improve risk stratification, including a lower threshold for monitoring for AKI and kidney dysfunction in their patients.

Small for gestational age at preterm birth identifies adverse neonatal outcomes more reliably than antenatal suspicion of fetal growth restriction

BACKGROUND

Fetal growth restriction (FGR) is an important reason for premature delivery and a leading cause of perinatal morbidity and mortality. We aimed to evaluate whether classification as small for gestational age (SGA; <10th centile) at birth or antenatal suspicion of FGR was more strongly associated with neonatal morbidity and mortality in preterm infants.

METHODS

A retrospective audit of infants born between 24 + 0 and 32 + 6 weeks of gestation from 2012-2019 and admitted to the Neonatal Unit at Mercy Hospital for Women (MHW). Infants were categorized according to whether FGR was listed as an antenatal complication in the medical records and whether they were SGA (<10th centile on Fenton chart) or appropriate for gestational age (AGA) at birth, and comparisons for neonatal outcomes were made.

RESULTS

371/2126 preterm infants (17.5%) had antenatal suspicion of FGR, and 166 (7.8%) were SGA at birth. No differences in any neonatal outcomes were found between infants with or without suspected FGR, except decreased intraventricular hemorrhage (IVH) in the FGR group. SGA classification was associated with increased rates of all morbidities other than IVH, including bronchopulmonary dysplasia, retinopathy of prematurity, and necrotizing enterocolitis, compared with the AGA group. Death was significantly higher in the SGA group (7.2%) compared with the AGA group (3.5%).

CONCLUSION

SGA by Fenton chart more reliably identified neonates at risk of adverse neonatal outcomes than antenatal suspicion of FGR, suggesting it is a reasonable clinical proxy. This most likely reflects the much lower tenth centile weight cutoffs on the Fenton charts compared to in-utero charts used antenatally to diagnose FGR based on ultrasound estimated fetal weight. SGA classification by Fenton approximately equates to <3rd centile on in-utero charts at our institution, therefore identifying the most severe FGR cases.

Intended delivery mode and neonatal outcomes in pregnancies with fetal growth restriction

Objective: To compare neonatal outcomes in pregnancies with fetal growth restriction (FGR) by intended delivery mode.Methods: This is a retrospective cohort study of singleton pregnancies with FGR that were delivered ≥34.0 weeks gestation. Neonatal outcomes were compared according to the intended delivery mode, which the attending obstetrician determined. Of note, none of the subjects had a contraindication to labor. Crude and adjusted odds ratios (ORs) and corresponding confidence intervals (CIs) were calculated via logistic regression models to assess the potential association between intended delivery mode and neonatal morbidity defined as a composite outcome (i.e. umbilical artery pH ≤7.1, 5-min Apgar score ≤7, admission to the neonatal intensive care unit, hypoglycemia, intrapartum fetal distress requiring expedited delivery, and perinatal death). A sensitivity analysis excluded intrapartum fetal distress requiring emergency cesarean delivery from the composite outcome since only patients with spontaneous labor or labor induction could meet this criterion. Potential confounders in the adjusted effects models included maternal age, body mass index, hypertensive disorders, diabetes, FGR type (i.e. early or late), and oligohydramnios.Results: Seventy-two (34%) patients had an elective cesarean delivery, 73 (34%) had spontaneous labor and were expected to deliver vaginally, and 67 (32%) underwent labor induction. The composite outcome was observed in 65.3%, 89%, and 88.1% of the groups mentioned above, respectively (p < 0.001). Among patients with spontaneous labor and those scheduled for labor induction, 63% and 47.8% required an emergency cesarean delivery for intrapartum fetal distress. Compared to elective cesarean delivery, spontaneous labor (OR 4.32 [95% CI 1.79, 10.42], p = 0.001; aOR 4.85 [95% CI 1.85, 12.66], p = 0.001), and labor induction (OR 3.92 [95% CI 1.62, 9.49] p = 0.002; aOR 5.29 [95% CI 2.01, 13.87], p = 0.001) had higher odds of adverse neonatal outcomes.Conclusion: In this cohort of FGR, delivering at ≥34 weeks of gestation, pregnancies with spontaneous labor, and those that underwent labor induction had higher odds of neonatal morbidity than elective cesarean delivery.

Biomarker screening in fetal growth restriction based on multiple RNA-seq studies

Objective

Fetal growth restriction (FGR) is a severe pathological complication associated with compromised fetal development. The early diagnosis and prediction for FGR are still unclear. Sequencing technologies present a huge opportunity to identify novel biomarkers. However, limitation of individual studies (e.g., long lists of dysregulated genes, small sample size and conflicting results) hinders the selection of the best-matched ones.

Study design

A multi-step bioinformatics analysis was performed. We separately reanalyzed data from four public RNA-seq studies, followed by a combined analysis of individual results. The differentially expressed genes (DEGs) were identified based on DESeq2. Then, function enrichment analyses and protein-protein interaction network (PPI) were conducted to screen for hub genes. The results were further verified by using external microarray data.

Results

A total of 65 dysregulated genes (50 down and 15 upregulated) were identified in FGR compared to controls. Function enrichment and PPI analysis revealed ten hub genes closely related to FGR. Validation analysis found four downregulated candidate biomarkers (CEACAM6, SCUBE2, DEFA4, and MPO) for FGR.

Conclusions

The use of omics tools to explore mechanism of pregnancies disorders contributes to improvements in obstetric clinical practice.

Quantitative Proteomics of Maternal Blood Plasma in Isolated Intrauterine Growth Restriction

Intrauterine growth restriction (IUGR) remains a significant concern in modern obstetrics, linked to high neonatal health problems and even death, as well as childhood disability, affecting adult quality of life. The role of maternal and fetus adaptation during adverse pregnancy is still not completely understood. This study aimed to investigate the disturbance in biological processes associated with isolated IUGR via blood plasma proteomics. The levels of 125 maternal plasma proteins were quantified by liquid chromatography-multiple reaction monitoring mass spectrometry (LC-MRM MS) with corresponding stable isotope-labeled peptide standards (SIS). Thirteen potential markers of IUGR (Gelsolin, Alpha-2-macroglobulin, Apolipoprotein A-IV, Apolipoprotein B-100, Apolipoprotein(a), Adiponectin, Complement C5, Apolipoprotein D, Alpha-1B-glycoprotein, Serum albumin, Fibronectin, Glutathione peroxidase 3, Lipopolysaccharide-binding protein) were found to be inter-connected in a protein-protein network. These proteins are involved in plasma lipoprotein assembly, remodeling, and clearance; lipid metabolism, especially cholesterol and phospholipids; hemostasis, including platelet degranulation; and immune system regulation. Additionally, 18 proteins were specific to a particular type of IUGR (early or late). Distinct patterns in the coagulation and fibrinolysis systems were observed between isolated early- and late-onset IUGR. Our findings highlight the complex interplay of immune and coagulation factors in IUGR and the differences between early- and late-onset IUGR and other placenta-related conditions like PE. Understanding these mechanisms is crucial for developing targeted interventions and improving outcomes for pregnancies affected by IUGR.