Brain-Sparing in Intrauterine Growth Restriction: Considerations for the Neonatologist

Differentially expressed genes in cotyledon of ewes fed mycotoxins

BACKGROUND

Ergot alkaloids (E+) are mycotoxins produced by the endophytic fungus, Epichloë coenophiala, in tall fescue that are associated with ergotism in animals. Exposure to ergot alkaloids during gestation reduces fetal weight and placental mass in sheep. These reductions are related to vasoconstrictive effects of ergot alkaloids and potential alterations in nutrient transport to the fetus. Cotyledon samples were obtained from eight ewes that were fed E+ (n = 4; E+/E+) or E- (endophyte-free without ergot alkaloids; n = 4; E-/E-) seed during both mid (d 35 to 85) and late (d 85-133) gestation to assess differentially expressed genes associated with ergot alkaloid induced reductions in placental mass and fetal weight, and discover potential adaptive mechanisms to alter nutrient supply to fetus.

RESULTS

Ewes fed E+/E+ fescue seed during both mid and late gestation had 20% reduction in fetal body weight and 33% reduction in cotyledon mass compared to controls (E-/E-). Over 13,000 genes were identified with 110 upregulated and 33 downregulated. Four genes had a |log2FC| > 5 for ewes consuming E+/E+ treatment compared to controls: LECT2, SLC22A9, APOC3, and MBL2. REViGO revealed clusters of upregulated genes associated glucose, carbohydrates, lipid, protein, macromolecular and cellular metabolism, regulation of wound healing and response to starvation. For downregulated genes, no clusters were present, but all enriched GO terms were associated with anion and monocarboxylic acid transport. The complement and coagulation cascade and the peroxisome proliferator-activated receptor signaling pathway were found to be enriched for ewes consuming E+/E+ treatment.

CONCLUSIONS

Consumption of ergot alkaloids during gestation altered the cotyledonary transcriptome specifically related to macronutrient metabolism, wound healing and starvation. These results show that ergot alkaloid exposure upregulates genes involved in nutrient metabolism to supply the fetus with additional substrates in attempts to rescue fetal growth.

Maternal sildenafil impairs the cardiovascular adaptations to chronic hypoxaemia in fetal sheep

KEY POINTS

Fetal growth restriction induces a haemodynamic response that aims to maintain blood flow to vital organs such as the brain, in the face of chronic hypoxaemia Maternal sildenafil treatment impairs the hypoxaemia-driven haemodynamic response and potentially compromises fetal development.

ABSTRACT

Inadequate substrate delivery to a fetus results in hypoxaemia and fetal growth restriction (FGR). In response, fetal cardiovascular adaptations redirect cardiac output to essential organs to maintain oxygen delivery and sustain development. However, FGR infants remain at risk for cardiovascular and neurological sequelae. Sildenafil citrate (SC) has been examined as a clinical therapy for FGR, but also crosses the placenta and may exert direct effects on the fetus. We investigated the effects of maternal SC administration on maternal and fetal cardiovascular physiology in growth-restricted fetal sheep. Fetal sheep (0.7 gestation) underwent sterile surgery to induce growth restriction by single umbilical artery ligation (SUAL) or sham surgery (control, AG). Fetal catheters and flow probes were implanted to measure carotid and femoral arterial blood flows. Ewes containing SUAL fetuses were randomized to receive either maternal administration of saline or SC (36 mg i.v. per day) beginning 4 days after surgery, and continuing for 20 days. Physiological recordings were obtained throughout the study. Antenatal SC treatment reduced body weight by 32% and oxygenation by 18% in SUAL compared to AG. SC did not alter maternal or fetal heart rate or blood pressure. Femoral blood flow and peripheral oxygen delivery were increased by 49% and 30% respectively in SUALSC compared to SUAL, indicating impaired cardiovascular adaptation to chronic hypoxaemia. Antenatal SC directly impairs the fetal haemodynamic response to chronic hypoxaemia. Consideration of the consequences upon the fetus should be paramount when administering interventions to the mother during pregnancy.

Near-Infrared spectroscopy for perfusion assessment and neonatal management

Term and preterm infants often present with adverse conditions after birth resulting in abnormal vital functions and severe organ failure, which are associated or sometimes caused by low oxygen and/or blood supply. Brain injury may lead to substantial mortality and morbidity often affecting long-term outcome. Standard monitoring techniques in the NICU focus on arterial oxygen supply and hemodynamics and include respiratory rate, heart rate, blood pressure and arterial oxygen saturation as measured by pulse oximetry but provide only limited information on end organ oxygen delivery. Near-Infrared Spectroscopy can bridge this gap by displaying continuous measurements of tissue oxygen saturation, providing information on the balance of oxygen delivery and consumption in organs of interest. Future techniques using multi-wavelength devices may provide additional information on oxidative metabolism in real time adding important information.

Antenatal corticosteroids in preterm small-for-gestational age infants: a systematic review and meta-analysis

OBJECTIVE

This study aimed to estimate the effect of antenatal corticosteroid administration on neonatal mortality and morbidity in preterm small-for-gestational age infants through a systematic review and meta-analysis.

DATA SOURCES

A predefined, systematic search was conducted through Ovid MEDLINE, Embase, Scopus, Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials, World Health Organization International Clinical Trial Registry Platform, and ClinicalTrials.gov yielding 5324 articles from 1970 to 2019.

STUDY ELIGIBILITY CRITERIA

Eligible studies compared neonatal morbidity and mortality among small-for-gestational age infants delivered preterm who received antenatal corticosteroids with those who did not.

METHODS

The primary outcome was neonatal mortality. Secondary outcomes were respiratory distress syndrome, necrotizing enterocolitis, intraventricular hemorrhage and periventricular leukomalacia, bronchopulmonary dysplasia or chronic lung disease of prematurity, or neonatal sepsis. We assessed heterogeneity by means of Higgins I² statistic and Cochran's Q test and calculated pooled odds ratios with 95% confidence intervals using random effects models.

RESULTS

A total of 16 observational cohort and case-control studies published from 1995 to 2018 met the selection criteria for the systematic review and included 8989 preterm small-for-gestational age infants. Antenatal corticosteroid administration was explicitly reported among 8376 small-for-gestational age infants; 4631 (55.3%) received antenatal corticosteroids and 3741 (44.7%) did not. Of note, 13 studies including 6387 preterm small-for-gestational age infants were then included in the meta-analysis. Neonatal mortality was significantly lower among infants who received antenatal corticosteroids than those who did not (12 studies: 12.8% vs 15.1%; pooled odds ratio, 0.63; 95% confidence interval, 0.46-0.86), with significant heterogeneity between studies (I²=55.1%; P=.011). There was no significant difference in respiratory distress syndrome (12 studies: odds ratio, 0.89; 95% confidence interval, 0.69-1.15), necrotizing enterocolitis (7 studies: odds ratio, 0.93; 95% confidence interval, 0.70-1.22), intraventricular hemorrhage and periventricular leukomalacia (10 studies: odds ratio, 0.82; 95% confidence interval, 0.56-1.20), bronchopulmonary dysplasia or chronic lung disease of prematurity (8 studies: odds ratio, 1.11; 95% confidence interval, 0.88-1.41), or neonatal sepsis (6 studies: odds ratio, 1.13; 95% confidence interval, 0.86-1.49).

CONCLUSION

These data indicate that antenatal corticosteroid administration reduces neonatal mortality in small-for-gestational age infants delivered preterm, with no apparent effect on neonatal morbidity. This supports the use of antenatal corticosteroids to reduce neonatal mortality in pregnancies with small-for-gestational age infants at risk of preterm birth.

The impact of intrauterine growth restriction on cytochrome P450 enzyme expression and activity

With the increased prevalence of non-communicable disease and availability of medications to treat these and other conditions, a pregnancy free from prescribed medication exposure is rare. Up to 99% of women take at least one medication during pregnancy. These medications can be divided into those used to improve maternal health and wellbeing (e.g., analgesics, antidepressants, antidiabetics, antiasthmatics), and those used to promote the baby's wellbeing in either fetal (e.g., anti-arrhythmics) or postnatal life (e.g., antenatal glucocorticoids). These medications are needed for pre-existing or coincidental illnesses in the mother, maternal conditions induced by the pregnancy itself through to conditions that arise in the fetus or that will be encountered by the newborn. Thus, medications administered to the mother may be used to treat the mother, the fetus or both. Metabolism of medications is regulated by a range of physiological processes that change during pregnancy. Other pathological processes such as placental insufficiency can in turn have both immediate and lifelong adverse health consequences for babies. Individuals born growth restricted are more likely to require medications but may also have an altered ability to metabolise these medications in fetal and postnatal life. This review aims to determine the effect of suboptimal fetal growth on the fetal expression of the drug metabolising enzymes (DMEs) that convert medications into active or inactive metabolites, and the transporters that remove both these medications and their metabolites from the fetal compartment.

Low FoxO expression in Drosophila somatosensory neurons protects dendrite growth under nutrient restriction

During prolonged nutrient restriction, developing animals redistribute vital nutrients to favor brain growth at the expense of other organs. In Drosophila, such brain sparing relies on a glia-derived growth factor to sustain proliferation of neural stem cells. However, whether other aspects of neural development are also spared under nutrient restriction is unknown. Here we show that dynamically growing somatosensory neurons in the Drosophila peripheral nervous system exhibit organ sparing at the level of arbor growth: Under nutrient stress, sensory dendrites preferentially grow as compared to neighboring non-neural tissues, resulting in dendrite overgrowth. These neurons express lower levels of the stress sensor FoxO than neighboring epidermal cells, and hence exhibit no marked induction of autophagy and a milder suppression of Tor signaling under nutrient stress. Preferential dendrite growth allows for heightened animal responses to sensory stimuli, indicative of a potential survival advantage under environmental challenges.

Effects of small for gestational age status on mortality and major morbidities in ≤750 g neonates

BACKGROUND

Controversy exists regarding the impact of small for gestational age (SGA = birth weight < 10th percentile) status on mortality and major morbidities.

AIM

To assess the effects of SGA on mortality and major morbidities in ≤750 gram (g) neonates.

STUDY DESIGN

Retrospective (01/2005-12/2017), single center study at a tertiary NICU.

SUBJECTS

SGA neonates ≤ 750 g.

OUTCOME

Effect of SGA status on mortality and major morbidities.

RESULTS

183 infants were enrolled. 103 (56.3%) were non-SGA (mean gestational age 25 + 1 weeks ± 9.9 days, mean birth weight 662.6 ± 75.2 g), and 80 (43.7%) SGA (mean gestational age 26 + 6 weeks ± 14.0 days, mean birth weight 543.9 ± 114.7 g). Mortality was 24.1% (non-SGA: 30/103 (29.1%), SGA: 14/80 (17.5%); p = 0.08). Univariable logistic regression analysis revealed a significant protective effect of SGA status on pneumothoraces (OR 0.28, 95%-CI [0.11-0.69]), IVH (≥3) (OR 0.38; 95%-CI [0.15-0.67]), and seizures (OR 0.09, 95%-CI [0.01-0.76]), but NEC (≥2a) occurred more frequently in SGA neonates (p = 0.024). Multiple logistic regression analysis found SGA status to negatively influence ROP (≥3) (OR 2.87, 95%-CI [1.14-7.23]) and need for home monitoring (OR 2.38, 95%-CI [1.05-5.41]). Other major morbidities (IVH, PVL, RDS, BPD, NEC, FIP, sepsis, hearing impairment) and mortality rates were not significantly affected, but distinct organ-specific patterns were seen.

CONCLUSION

SGA had negative effects on the rate of severe ROP and the need for home monitoring, but other major morbidities as well as mortality rates were not significantly affected. In the future, it will be important to delineate underlying pathophysiological mechanisms that contribute to this pattern.

Association between infertility treatment and intrauterine growth: a multilevel analysis in a retrospective cohort study

OBJECTIVES

This study aimed to identify intrauterine growth differences according to infertility treatment compared with spontaneous conception and to describe intrauterine growth trajectories.

DESIGN

Retrospective cohort study.

SETTING

A single primary and tertiary medical centre in Japan.

PARTICIPANTS

This study included singleton pregnant women with prenatal check-ups and delivery at the University of Yamanashi Hospital between 1 July 2012 and 30 September 2017. Patients were divided into four groups: spontaneous conception, infertility treatment without assisted reproductive technology (ART), fresh-embryo transfer and frozen embryo transfer (FET).

INTERVENTIONS

Differences in intrauterine growth according to the infertility treatment, including ART, and birth weight were evaluated. Multilevel analysis was employed to evaluate intrauterine growth trajectories stratified by the sex of the offspring.

PRIMARY OUTCOME MEASURE

Estimated fetal weight (EFW) assessed by ultrasound examination.

RESULTS

We assessed data from 37 239 prenatal examination results from 2377 pregnant women (spontaneous conception, n=1764; infertility treatment without ART, n=171; fresh-embryo transfer, n=112; and FET, n=330) in the final analysis. Multilevel analysis was adjusted for gestation duration, gestation period, parity, hypertensive disorders of pregnancy, type of infertility treatment, maternal age, smoking status, placenta previa, thyroid disease, gestational diabetes mellitus and the interaction between each potential confounding factor and gestation duration. In male fetuses, the interaction between FET and gestational duration (estimate: 0.36; 95% CI: 0.06 to 0.67) significantly affected the EFW. Similarly, in female fetuses, FET (estimate: -69.85; 95% CI: -112.09 to -27.61) and the interaction between FET and gestation duration (estimate: 0.57; 95% CI: 0.28 to 0.87) significantly affected the EFW.

CONCLUSIONS

This study shows that FET affects intrauterine growth trajectory from the second trimester to term, particularly in female fetuses. Our findings require further prospective research to examine the effect of infertility treatment on fetal growth.

Maternal supplementation with citrulline or arginine during gestation impacts fetal amino acid availability in a model of intrauterine growth restriction (IUGR)

BACKGROUND

Supplementing maternal diet with citrulline or arginine during gestation was shown to enhance fetal growth in a model of IUGR induced by maternal dietary protein restriction in the rat.

OBJECTIVE

The aims of this study were to determine in the same model whether maternal supplementation with citrulline or arginine would increase 1) citrulline and arginine concentration in fetal circulation; 2) the expression of placental amino acid transporters, and 3) the fetal availability of essential amino acids.

METHODS

Pregnant rats (n = 8 per group) were fed either an isocaloric control (20% protein, NP) or a low protein (LP, 4% protein) diet, either alone or supplemented with 2 g/kg/d of l-citrulline (LP + CIT) or isonitrogenous Arginine (LP + ARG) in drinking water throughout gestation. Fetuses were extracted by C-section on the 21st day of gestation. The gene expression of system A (Slc38a1, Slc38a2, and Slc38a4) and L (Slc7a2, Slc7a5, Slc7a8) amino acid transporters was measured in placenta and amino acid concentrations determined in maternal and fetal plasma.

RESULTS

Maternal LP diet decreased fetal (4.01 ± 0.03 vs. 5.45 ± 0.07 g, p < 0.0001) and placental weight (0.617 ± 0.01 vs. 0.392 ± 0.04 g, p < 0.001), by 26 and 36% respectively, compared with NP diet. Supplementation with either CIT or ARG increased fetal birth weight by ≈ 5 or 11%, respectively (4.21 ± 0.05 and 4.48 ± 0.05 g vs. 4.01 ± 0.03 g, p < 0.05). CIT supplementation produced a 5- and 2-fold increase in fetal plasma citrulline and arginine, respectively, whereas ARG supplementation only increased fetal arginine concentration. LP diet led to lower placental SNAT 4 mRNA, and higher LAT2 and SNAT1 expression, compared with NP. SNAT4, 4hFC, LAT2 mRNA were up-regulated in LP + CIT and LP + ARG group compared with the un-supplemented LP group. Higher level of LAT1 mRNA was also observed in the LP + CIT group than in the LP group (p < 0.01). SNAT2 expression was unchanged in response to CIT or ARG supplementation. Fetal amino acid concentrations were decreased by LP diet, and were not restored by CIT or ARG supplementation.

CONCLUSIONS

The current findings confirm supplementation with citrulline or arginine enhances fetal growth in a rat model of IUGR. They further suggest that: 1) citrulline and arginine administered orally to the pregnant mother may reach fetal circulation; 2) citrulline effectively raises fetal arginine availability; and 3) although it failed to increase the concentrations of essential amino acids in fetal plasma, citrulline or arginine supplementation upregulates the gene expression of several placental amino acid transporters.

Predictive possibility of the transverse cerebellar diameter to abdominal circumference ratio for small-for-gestational-age fetus suspected as a cause of maternal placental syndromes: a retrospective cohort study

Objective: To examine whether fetal transverse cerebellar diameter (TCD) to abdominal circumference (AC) ratio can predict small-for-gestational age suspected as a cause of maternal placental syndromes (SGA-MPS).Methods: We evaluated 473 women who underwent ultrasound examinations at 24-28 weeks of gestation. A receiver operating characteristic curve was used to determine the TCD/AC ratio thresholds to predict SGA-MPS. We used multivariable logistic regression analysis to examine the association.Results: TCD/AC ratio>14.37 was associated with SGA-MPS.Conclusions: Accurate risk stratification using the TCD/AC ratio could assist in managing patients with small-for-gestational-age fetuses at risk of developing MPS-associated adverse outcomes.

Cognitive Profiles and Brain Volume Are Affected in Patients with Silver-Russell Syndrome

CONTEXT

There is little information on cognitive function in Silver-Russell syndrome (SRS), and no neuroimaging studies are available so far.

OBJECTIVE

To assess cognitive function and brain volumes in patients with SRS.

DESIGN/SETTING

Wechsler Intelligence Scale and brain magnetic resonance on a 3-Tesla scanner with Voxel-based morphometry analysis were performed between 2016 and 2018 in a single tertiary university center.

PARTECIPANTS

38 white subjects with clinical diagnosis of SRS confirmed by molecular analysis: 30 of these patients (mean age 12.6 ± 10 years) were enrolled for cognitive assessment; 23 of the 30 performed neuroimaging sequences. A control group of 33 school-aged children performed cognitive assessment while 65 age and sex-matched volunteers were included for the neuroradiological assessment.

MAIN OUTCOMES

Intelligence quotient, Verbal Comprehension Index (VCI), Perceptual Reasoning Index (PRI), Working Memory Index (WMI), Processing Speed Index, and brain volume.

RESULTS

The mean overall IQ score was 87.2 ± 17, and it was significantly lower in the maternal uniparental disomy of chromosome 7 (mUPD7) group at the age of 6 to 16 years compared to loss of methylation on chromosome 11p15 (11p15 LOM) group and to controls. VCI, PRI, and WMI were significantly higher in 11p15 LOM group and in control group than in mUPD7 group at the age of 6 to 16 years. There were no significant differences in cognitive scores between 11p15 LOM school-aged patients and the control group. SRS patients showed lower brain volume compared to controls at the frontal/temporal poles and globi pallidi.

CONCLUSIONS

Patients with mUPD7 had an impaired cognitive profile. The brain volume at the frontal/temporal lobes and at the globi pallidi was reduced in patients with SRS.

Effects of Maternal Sildenafil Treatment on Vascular Function in Growth-Restricted Fetal Sheep

Objective- The objective of this study was to investigate the effect of intravenous maternal sildenafil citrate (SC) administration on vascular function in growth-restricted fetal sheep. Approach and Results- Fetal growth restriction (FGR) results in cardiovascular adaptations that redistribute cardiac output to optimize suboptimal intrauterine conditions. These adaptations result in structural and functional cardiovascular changes, which may underlie postnatal neurological and cardiovascular sequelae. Evidence suggests SC, a potent vasodilator, may improve FGR. In contrast, recent clinical evidence suggests potential for adverse fetal consequence. Currently, there is limited data on SC effects in the developing fetus. We hypothesized that SC in utero would improve vascular development and function in an ovine model of FGR. Preterm lambs (0.6 gestation) underwent sterile surgery for single umbilical artery ligation or sham (control, appropriately grown) surgery to replicate FGR. Ewes received continuous intravenous SC (36 mg/24 h) or saline from surgery until 0.83 gestation. Fetuses were delivered and immediately euthanized for collection of femoral and middle cerebral artery vessels. Vessel function was assessed via in vitro wire myography. SC exacerbated growth restriction in growth-restricted fetuses and resulted in endothelial dysfunction in the cerebral and femoral vasculature, irrespective of growth status. Dysfunction in the cerebral circulation is endothelial, whereas smooth muscle in the periphery is the origin of the deficit. Conclusions- SC crosses the placenta and alters key fetal vascular development. Extensive studies are required to investigate the effects of SC on fetal development to address safety before additional use of SC as a treatment.

Data-Mining Approach on Transcriptomics and Methylomics Placental Analysis Highlights Genes in Fetal Growth Restriction

Intrauterine Growth Restriction (IUGR) affects 8% of newborns and increases morbidity and mortality for the offspring even during later stages of life. Single omics studies have evidenced epigenetic, genetic, and metabolic alterations in IUGR, but pathogenic mechanisms as a whole are not being fully understood. An in-depth strategy combining methylomics and transcriptomics analyses was performed on 36 placenta samples in a case-control study. Data-mining algorithms were used to combine the analysis of more than 1,200 genes found to be significantly expressed and/or methylated. We used an automated text-mining approach, using the bulk textual gene annotations of the discriminant genes. Machine learning models were then used to explore the phenotypic subgroups (premature birth, birth weight, and head circumference) associated with IUGR. Gene annotation clustering highlighted the alteration of cell signaling and proliferation, cytoskeleton and cellular structures, oxidative stress, protein turnover, muscle development, energy, and lipid metabolism with insulin resistance. Machine learning models showed a high capacity for predicting the sub-phenotypes associated with IUGR, allowing a better description of the IUGR pathophysiology as well as key genes involved.

Effect of Intrauterine Growth Restriction on Cerebral Regional Oxygen Saturation in Preterm and Term Neonates during Immediate Postnatal Transition

BACKGROUND

Intrauterine growth restriction (IUGR) is associated with adverse perinatal outcome. Affected fetuses commonly display typical blood flow redistribution towards the brain ("brain sparing"). Accordingly, increased cerebral oxygen saturation has been observed in IUGR neonates within the first days of life.

AIM

The aim of our study was to assess cerebral oxygenation behavior during immediate neonatal transition in IUGR infants.

METHODS

This is a retrospective single-center observational cohort study. Cerebral regional oxygen saturation (crSO2) was measured with near-infrared spectroscopy in neonates during the first 15 min after birth. Neonates with IUGR (IUGR group) were matched for gestational age (±1 week) and gender with neonates that were appropriate for gestational age (AGA). The AGA:IUGR matching ratio was 3:1. Arterial oxygen saturation (SpO2), heart rate (HR), crSO2, and cerebral fractional tissue oxygen extraction (cFTOE) were compared between the groups.

RESULTS

Between August 2010 and October 2017, 45 neonates with IUGR were identified and matched to 135 AGA neonates. Mean gestational age was 33.1 ± 3.0 weeks in the IUGR group and 33.5 ± 2.7 weeks in the AGA group. Mean birth weight was 1,559 ± 582 g in the IUGR group and 2,051 ± 679 g in the AGA group. There was a significant group difference in crSO2 beginning at 5 min and continuing for the rest of the observation time with higher crSO2 values in the IUGR group (main effect group: p = 0.011; interaction time × group: p = 0.039). In cFTOE, a significant difference could be observed at 5-9 and 11-13 min with lower rates of oxygen extraction in the IUGR group (main effect group: p = 0.025; interaction time × group: p = 0.463). Concerning SpO2 and HR, there was no significant difference between the IUGR and the AGA neonates.

CONCLUSION

Neonates of the IUGR group did show significantly higher crSO2 values and significantly lower cFTOE values already during immediate neonatal transition compared to the AGA group.

Fetal Brain-Sparing, Postnatal Cerebral Oxygenation, and Neurodevelopment at 4 Years of Age Following Fetal Growth Restriction

Objectives: To assess the role of fetal brain-sparing and postnatal cerebral oxygen saturation (r_cSO₂) as determinants of long-term neurodevelopmental outcome following fetal growth restriction (FGR). Methods: This was a prospective follow-up study of an FGR cohort of 41 children. Prenatally, the presence of fetal brain-sparing (cerebroplacental ratio < 1) was assessed by Doppler ultrasound. During the first two days after birth, r_cSO₂ was measured with near-infrared spectroscopy. At 4 years of age, intelligence (IQ points), behavior (T-scores), and executive function (T-scores) were assessed using the Wechsler Preschool and Primary Scale of Intelligence, Child Behavior Checklist, and Behavior Rating Inventory of Executive Function-Preschool Version, respectively. Using linear regression analyses, we tested the association (p < 0.05) between brain-sparing/r_cSO₂ and normed neurodevelopmental scores. Results: Twenty-six children (gestational age ranging from 28.0 to 39.9 weeks) participated in the follow-up at a median age of 4.3 (range: 3.6 to 4.4) years. Autism spectrum disorder was reported in three children (11.5%). Fetal brain-sparing was associated with better total and externalizing behavior (betas: -0.519 and -0.494, respectively). R_cSO₂ levels above the lowest quartile, particularly on postnatal day 2 (≥ 77%), were associated with better total and internalizing behavior and executive functioning (betas: -0.582, -0.489, and -0.467, respectively), but also lower performance IQ (beta: -0.530). Brain-sparing mediated some but not all of these associations. Conclusions: In this FGR cohort, fetal brain-sparing and high postnatal r_cSO₂ were-independently, but also as a reflection of the same mechanism-associated with better behavior and executive function. Postnatal cerebral hyperoxia, however, was negatively associated with brain functions responsible for performance IQ.

Hydrolyzed Fat Formula Increases Brain White Matter in Small for Gestational Age and Appropriate for Gestational Age Neonatal Piglets

Background: Intrauterine growth restriction is a common cause of small for gestational age (SGA) infants worldwide. SGA infants are deficient in digestive enzymes required for fat digestion and absorption compared to appropriate for gestational age (AGA) infants, putting them at risk for impaired neurocognitive development. Objective: The objective was to determine if a hydrolyzed fat (HF) infant formula containing soy free fatty acids, 2-monoacylglycerolpalmitate, cholesterol, and soy lecithin could increase brain tissue incorporation of essential fatty acids or white matter to enhance brain development in SGA and AGA neonatal piglet models. Methods: Sex-matched, littermate pairs of SGA (0.5-0.9 kg) and AGA (1.2-1.8 kg) 2 days old piglets (N = 60) were randomly assigned to control (CON) or HF formula diets in a 2 × 2 factorial design. On day 14, 24 piglets were used for hippocampal RNA-sequencing; the rest began a spatial learning task. On days 26-29, brain structure was assessed by magnetic resonance imaging (MRI). Cerebellum and hippocampus were analyzed for fatty acid content. Results: SGA piglets grew more slowly than AGA piglets, with no effect of diet on daily weight gain or weight at MRI. HF diet did not affect brain weight. HF diet increased relative volumes of 7 brain regions and white matter (WM) volume in both SGA and AGA piglets. However, HF did not ameliorate SGA total WM integrity deficits. RNA sequencing revealed SGA piglets had increased gene expression of synapse and cell signaling pathways and decreased expression of ribosome pathways in the hippocampus compared to AGA. HF decreased expression of immune response related genes in the hippocampus of AGA and SGA piglets, but did not correct gene expression patterns in SGA piglets. Piglets learned the T-maze task at the same rate, but SGA HF, SGA CON, and AGA HF piglets had more accurate performance than AGA CON piglets on reversal day 2. HF increased arachidonic acid (ARA) percentage in the cerebellum and total ARA in the hippocampus. Conclusions: HF enhanced brain development in the neonatal piglet measured by brain volume and WM volume in specific brain regions; however, more studies are needed to assess long-term outcomes.

Prenatal Use of Sildenafil in Fetal Growth Restriction and Its Effect on Neonatal Tissue Oxygenation-A Retrospective Analysis of Hemodynamic Data From Participants of the Dutch STRIDER Trial

Objective: Sildenafil is under investigation as a potential agent to improve uteroplacental perfusion in fetal growth restriction (FGR). However, the STRIDER RCT was halted after interim analysis due to futility and higher rates of persistent pulmonary hypertension and mortality in sildenafil-exposed neonates. This hypothesis-generating study within the Dutch STRIDER trial sought to understand what happened to these neonates by studying their regional tissue oxygen saturation (rSO₂) within the first 72 h after birth. Methods: Pregnant women with FGR received 25 mg placebo or sildenafil thrice daily within the Dutch STRIDER trial. We retrospectively analyzed the cerebral and renal rSO₂ monitored with near-infrared spectroscopy (NIRS) in a subset of neonates admitted to two participating neonatal intensive care units, in which NIRS is part of standard care. Secondarily, blood pressure and heart rate were analyzed to aid interpretation. Differences in oxygenation levels and interaction with time (slope) between placebo- and sildenafil-exposed groups were tested using mixed effects analyses with multiple comparisons tests. Results: Cerebral rSO₂ levels were not different between treatment groups (79 vs. 77%; both n = 14) with comparable slopes. Sildenafil-exposed infants (n = 5) showed lower renal rSO₂ than placebo-exposed infants (n = 6) during several time intervals on day one and two. At 69-72 h, however, the sildenafil group showed higher renal rSO₂ than the placebo group. Initially, diastolic blood pressure was higher and heart rate lower in the sildenafil than the placebo group, which changed during day two. Conclusions: Although limited by sample size, our data suggest that prenatal sildenafil alters renal but not cerebral oxygenation in FGR neonates during the first 72 post-natal hours. The observed changes in renal oxygenation could reflect a vasoconstrictive rebound from sildenafil. Similar changes observed in accompanying vital parameters support this hypothesis.

The Cerebral Hemodynamic Response to Pain in Preterm Infants With Fetal Growth Restriction

Background: Preterm infants undergoing intensive care often experience painful procedures such as heel lance for blood sampling. Knowledge of the cerebral hemodynamic response to painful stimuli contributes to understanding of cortical pain processing and the neurovascular network in the preterm brain. Previous research has demonstrated cerebral hemodynamic responses using near-infrared spectroscopy (NIRS) after noxious stimuli in infants appropriately grown for age (AGA). But this has not been studied in infants born small for gestational age after fetal growth restriction (FGR). FGR infants differ in brain development due to utero-placental insufficiency leading to the intrauterine growth restriction, and cerebral response to pain may be altered. Objectives: We aimed to compare the cerebral hemodynamic response to painful stimuli (heel lance) in FGR and AGA infants. Methods: Preterm FGR infants (n = 20) and AGA infants (n = 15) born at 28-32 weeks' gestation were studied at mean ± SD postnatal age of 11.5 ± 2.4 and 10.5 ± 2.4 days, respectively. Infants had baseline echocardiographic assessment of ductus arteriosus and stroke volume. They were monitored with NIRS for changes in tissue oxygenation index (TOI, %), and oxygenated, deoxygenated, and total hemoglobin (ΔO₂Hb, ΔHHb, and ΔTHb) in contralateral and ipsilateral cerebral hemispheres, during a heel lance. Results: At baseline, FGR infants had significantly lower TOI, higher heart rate, and lower stroke volume compared to AGA infants. Most infants in both groups showed increase in each of the NIRS parameters in the contralateral hemisphere following heel lance. However, more AGA infants (6/15) showed decreased ΔTHb compared to FGR infants (1/20) (p = 0.016). The magnitude of cerebral hemodynamic response and time to response did not differ between FGR and AGA infants. FGR infants showed larger ΔO₂Hb in the contralateral compared to ipsilateral cortex (p = 0.05). Conclusion: Preterm FGR infants have reduced stroke volume and lower cerebral oxygenation compared to AGA infants in the second to third week of life. FGR infants show similar cerebral hemodynamic responses to noxious stimuli compared to AGA infants. However, FGR infants are less likely to have a cerebral vasoconstrictive response, possibly due to cerebrovascular changes following placental insufficiency and brain sparing in-utero.

Antenatal Magnesium Sulfate and Preeclampsia Differentially Affect Neonatal Cerebral Oxygenation

INTRODUCTION

Magnesium sulfate (MgSO4) is frequently administered for maternal and fetal neuroprotection in preeclampsia (PE) and imminent preterm birth, respectively.

OBJECTIVE

To assess whether MgSO4 affects neonatal cerebral oxygenation, blood flow, and cerebral autoregulation (CAR) during the first postnatal days independently from PE.

METHODS

148 neonates <32 weeks gestational age were included. Cerebral fractional tissue oxygen extraction (cFTOE) was extracted from a daily 2-h period, during which peak systolic blood flow velocity (PSV) and resistance index (RI) of the pericallosal artery were obtained. The percent time of impaired CAR (correlation coefficient between mean arterial blood pressure and cerebral oxygen saturation >0.5) was determined. Linear mixed models were applied.

RESULTS

MgSO4 exposure was recorded in 77 neonates. Twenty-nine neonates were born following PE. MgSO4 independently lowered cFTOE (B: -0.026, 95% CI: -0.050 to 0.002, p < 0.05) but did not affect PSV and RI. PE was associated with a lower cFTOE (B: -0.041, 95% CI: -0.067 to -0.015, p < 0.05) and a tendency towards both lower PSV (B: -4.285, 95% CI: -9.067 to 0.497, p < 0.1) and more impaired CAR (B: 4.042, 95% CI: -0.028 to 8.112, p < 0.1), which seemed to be strongly mediated by fetal brain sparing. MgSO4 did not alter CAR.

CONCLUSIONS

In contrast to fetal brain sparing in PE, MgSO4 seems to lower cFTOE by lowering cerebral oxygen demands in preterm neonates without affecting the cerebrovasculature.

The brain-placental axis: Therapeutic and pharmacological relevancy to pregnancy

The placenta plays a critical role in mammalian reproduction. Although it is a transient organ, its function is indispensable to communication between the mother and fetus, and supply of nutrients and oxygen to the growing fetus. During pregnancy, the placenta is vulnerable to various intrinsic and extrinsic conditions which can result in increased risk of fetal neurodevelopmental disorders as well as fetal death. The placenta controls the neuroendocrine secretion in the brain as a means of adaptive processes to safeguard the fetus from adverse programs, to optimize fetal development and other physiological changes necessary for reproductive success. Although a wealth of information is available on neuroendocrine functions in pregnancy, they are largely limited to the regulation of hypothalamus-pituitary-adrenal/gonad (HPA/ HPG) axis, particularly the oxytocin and prolactin system. There is a major gap in knowledge on systems-level functional interaction between the brain and placenta. In this review, we aim to outline the current state of knowledge about the brain-placental axis with description of the functional interactions between the placenta and the maternal and fetal brain. While describing the brain-placental interactions, a special emphasis has been given on the therapeutics and pharmacology of the placental receptors to neuroligands expressed in the brain during gestation. As a key feature of this review, we outline the prospects of integrated pharmacogenomics, single-cell sequencing and organ-on-chip systems to foster priority areas in this field of research. Finally, we remark on the application of precision genomics approaches to study the brain-placental axis in order to accelerate personalized medicine and therapeutics to treat placental and fetal brain disorders.

Do Doppler Changes Reflect Pathology of Placental Vascular Lesions in IUGR Pregnancies?

OBJECTIVES

Doppler assessment of uteroplacental (UP) and fetoplacental (FP) circulation detects abnormal waveforms in intrauterine growth-restricted (IUGR) pregnancies. Similarly, histopathology also reveals lesions of vascular compromise in IUGR placenta. We evaluated an association between Doppler and histopathological (HP) assessment of the maternal and fetal circulation in IUGR.

METHODS

IUGR cases with both Doppler and histopathology assessment were selected from our database. Doppler patterns recorded UP and FP insufficiency. The HP vascular lesions were classified as maternal vascular underperfusion and fetal thrombotic vasculopathy (FTV). IUGRs were grouped based on (i) presence of preeclampsia (PE), (ii) clinical onset (early vs late) of IUGR (early onset [EO]/late onset), and (iii) gestational age (term, T/preterm, PT).

RESULTS

Abnormal Doppler waveforms were present in 69 of the total 88 IUGR cases (78.4%). The most frequent pattern was fetoplacental insufficiency (FPI) (66%) which was combined with uteroplacental insufficiency (UPI) in 49%. HP showed vascular lesions in 52.3% and most frequent was FTV (38%). PE-associated IUGR (n = 49) had higher UPI pattern (75.5% vs 43.6%, P = .004), while normotensive IUGR had higher FPI pattern (28.2% vs 8.2%, P = .01). EO-IUGR (n = 55) and PT-IUGR (n = 52) had significant abnormal Doppler waveforms (P < .05) with higher combined patterns and brain sparing. Doppler was more sensitive for fetal vascular lesions than maternal (75.8% vs 66.7%). However, 42% of cases with normal Doppler findings showed HP vascular lesions.

CONCLUSION

IUGR pregnancies harbor significant vascular compromise. Fetal circulatory lesions were more common in IUGR pregnancies. In a significant number of cases with normal Doppler report, vascular lesions were identified on histopathology, emphasizing placental examination in all cases of IUGR.

Developmental responses to early-life adversity: Evolutionary and mechanistic perspectives

Adverse ecological and social conditions during early life are known to influence development, with rippling effects that may explain variation in adult health and fitness. The adaptive function of such developmental plasticity, however, remains relatively untested in long-lived animals, resulting in much debate over which evolutionary models are most applicable. Furthermore, despite the promise of clinical interventions that might alleviate the health consequences of early-life adversity, research on the proximate mechanisms governing phenotypic responses to adversity have been largely limited to studies on glucocorticoids. Here, we synthesize the current state of research on developmental plasticity, discussing both ultimate and proximate mechanisms. First, we evaluate the utility of adaptive models proposed to explain developmental responses to early-life adversity, particularly for long-lived mammals such as humans. In doing so, we highlight how parent-offspring conflict complicates our understanding of whether mothers or offspring benefit from these responses. Second, we discuss the role of glucocorticoids and a second physiological system-the gut microbiome-that has emerged as an additional, clinically relevant mechanism by which early-life adversity can influence development. Finally, we suggest ways in which nonhuman primates can serve as models to study the effects of early-life adversity, both from evolutionary and clinical perspectives.

Region-specific changes in Mus musculus brain size and cell composition under chronic nutrient restriction

Nutrition is one of the most influential environmental factors affecting the development of different tissues and organs. It is suggested that under nutrient restriction the growth of the brain is spared as a result of the differential allocation of resources from other organs. However, it is not clear whether this sparing occurs brain-wide. Here, we analyzed morphological changes and cell composition in different regions of the offspring mouse brain after maternal exposure to nutrient restriction during pregnancy and lactation. Using high-resolution magnetic resonance imaging, we found that brain regions were differentially sensitive to maternal protein restriction and exhibited particular patterns of volume reduction. The cerebellum was reduced in absolute and relative volume, while cortex volume was relatively preserved. Alterations in cell composition (examined by the isotropic fractionator method) and organization of white matter (measured by diffusor tensor images) were also region specific. These changes were not related to the metabolic rate of the regions and were only partially explained by their specific growth trajectories. This study is a first step towards understanding the mechanisms of regional brain sparing at microstructural and macrostructural levels resulting from undernutrition.

Early psychosocial development of small for gestational age and intrauterine growth-restricted children: a systematic review

OBJECTIVE

To examine evidence regarding psychosocial development from one month to four years of age in small for gestational age and intrauterine growth-restricted children.

STUDY DESIGN

Studies were included if participants met criteria for small for gestational age or intrauterine growth restriction, follow-up was from age 1 month to 4 years, methods were described, and appropriate comparison groups were included. Methodological quality of included studies was assessed using quality-appraisal guidelines.

RESULTS

Of 3216 studies reviewed, 24 were included. Poorer psychosocial development was described for small for gestational age children in 15 and for intrauterine growth-restricted children in 3 studies. Only 5 studies measured placental insufficiency using Doppler ultrasound. Study heterogeneity limited synthesis and interpretation.

CONCLUSIONS

Although evidence suggests that small for gestational age children are at risk of poorer early childhood psychosocial outcomes, further research is required to clarify whether placental insufficiency is associated with poorer early psychosocial development.

Preeclampsia and intrauterine growth restriction: Role of human umbilical cord mesenchymal stem cells-trophoblast cross-talk

Background

Oxidative stress is involved in the pathogenesis and maintenance of pregnancy-related disorders, such as intrauterine growth restriction (IUGR) and preeclampsia (PE). Human umbilical cord mesenchymal stem cells (hUMSCs) have been suggested as a possible therapeutic tool for the treatment of pregnancy-related disorders in view of their paracrine actions on trophoblast cells.

Objectives

To quantify the plasma markers of peroxidation in patients affected by PE and IUGR and to examine the role of oxidative stress in the pathophysiology of PE and IUGR in vitro by using hUMSCs from physiological and pathological pregnancies and a trophoblast cell line (HTR-8/SVneo).

Study design

In pathological and physiological pregnancies the plasma markers of oxidative stress, arterial blood pressure, serum uric acid, 24h proteinuria, weight gain and body mass index (BMI) were examined. Furthermore, the pulsatility index (PI) of uterine and umbilical arteries, and of fetal middle cerebral artery was measured. In vitro, the different responses of hUMSCs, taken from physiological and pathological pregnancies, and of HTR-8/SVneo to pregnancy-related hormones in terms of viability and nitric oxide (NO) release were investigated. In some experiments, the above measurements were performed on co-cultures between HTR-8/SVneo and hUMSCs.

Results

The results obtained have shown that in pathological pregnancies, body mass index, serum acid uric, pulsatility index in uterine and umbilical arteries and markers of oxidative stress were higher than those found in physiological ones. Moreover, in PE and IUGR, a relation was observed between laboratory and clinical findings and the increased levels of oxidative stress. HTR-8/SVneo and hUMSCs showed reduced viability and increased NO production when stressed with H₂O₂. Finally, HTR-8/SVneo cultured in cross-talk with hUMSCs from pathological pregnancies showed a deterioration of cell viability and NO release when treated with pregnancy-related hormones.

Conclusion

Our findings support that hUMSCs taken from patients affected by PE and IUGR have significant features in comparison with those from physiologic pregnancies. Moreover, the cross-talk between hUMSCs and trophoblast cells might be involved in the etiopathology of IUGR and PE secondary to oxidative stress.

The role of magnesium sulfate (MgSO4) in fetal neuroprotection

Prevention of neurologic disability associated with preterm birth is one of the major challenges in current perinatal medicine. Magnesium sulfate (MgSO₄), the focus of this review has been proposed as major step forward for that matter. MgSO₄ is easily accessible, cheap, and has been proposed as a mandatory part of the management of inevitable preterm birth. The results of the various RCT's on the use of MgSO₄ for neuroprotection has been the subject of many systematic reviews, other studies focused on dosing schedules, side effects and only a few focused on exploring magnesium's mechanism of action. Meanwhile, many guidelines worldwide have plugged MgSO₄ as an essential ingredient of daily best practice when managing inevitable preterm birth because it has been shown to reduce the risk of severe neurologic deficit, in particular, cerebral palsy in appropriately selected patients. The more premature, the greater benefit associated with the use of antenatal MgSO₄. The dose of 4 g given intravenously 15 min continued by 1 g/h until maximum 24 h and minimum for 4 h is the standard regiment proposed in most guidelines. It should be noted, however, that a recent study found that a total dose of 64 g was associated with the maximum protective effect. Only the protocol used by the largest RCT, the BEAM trial, with a loading dose of 6 g initially followed by a 2-g/h maintenance dose, if continued for 24 h would give a total dose over 50 g. Other studies report on an increased risk of neonatal death with these high doses. Several studies expressed concerns about the risk of serious side effects for both mother and neonate. The results from the systematic review showed that the most commonly used dosage, 4 g bolus continued by 1 g/h maintenance, did not increase neonatal mortality and other suspected neonatal complication such as neonatal asphyxia, spontaneous intestinal perforation, necrotizing enterocolitis, and feeding intolerance. Giving a single bolus injection of 4 g MgSO4 for stimulating BDNF production in highly "suspicious" preterm labor, and 4 g again when preterm birth become inevitable may be best from a safety perspective and also appears to have a stronger rationale.

Transitional fetal hemodynamics and gas exchange in premature postpartum adaptation: immediate vs. delayed cord clamping

Background

Recent studies suggest that delayed cord clamping (DCC) is advantageous for achieving hemodynamic stability and improving oxygenation compared to the immediate cord clamping (ICC) during fetal-to-neonatal transition yet there is no quantitative information on hemodynamics and respiration, particularly for pre-term babies and fetal disease states. Therefore, the objective of this study is to investigate the effects of ICC and DCC on hemodynamics and respiration of the newborn preterm infants in the presence of common vascular pathologies.

Methods

A computational lumped parameter model (LPM) of the placental and respiratory system of a fetus is developed to predict blood pressure, flow rates and oxygen saturation. Cardiovascular system at different gestational ages (GA) are modeled using scaling relations governing fetal growth with the LPM. Intrauterine growth restriction (GR), patent ductus arteriosus (PDA) and respiratory distress syndrome (RDS) were modeled for a newborn at 30 weeks GA. We also formulated a "severity index (SI)" which is a weighted measure of ICC vs. DCC based on the functional parameters derived from our model and existing neonatal disease scoring systems.

Results

Our results show that transitional hemodynamics is smoother in DCC compared to ICC for all GAs. Blood volume of the neonate increases by 10% for moderately preterm and term infants (32-40 wks) and by 15% for very and extremely preterm infants (22-30 wks) with DCC compared to ICC. DCC also improves the cardiac output and the arterial blood pressure by 17% in term (36-40 wks), by 18% in moderately preterm (32-36 wks), by 21% in very preterm (28-32 wks) and by 24% in extremely preterm (20-28 wks) births compared to the ICC. A decline in oxygen saturation is observed in ICC received infants by 20% compared to the DCC received ones. At 30 weeks GA, SI were calculated for healthy newborns (1.18), and newborns with GR (1.38), PDA (1.22) and RDS (1.2) templates.

Conclusion

Our results suggest that DCC provides superior hemodynamics and respiration at birth compared to ICC. This information will help preventing the complications associated with poor oxygenation arising in premature births and pre-screening the more critical babies in terms of their cardiovascular severity.

In utero sFlt-1 exposure differentially affects gene expression patterns in fetal liver

The soluble fms-like tyrosine kinase factor 1 (sFlt-1) is a major contributor to antiangiogenesis during preeclampsia. However, little is known about the effects of sFlt-1 on fetal health. In this study we aim to evaluate the effects of the sFlt-1 concentration during pregnancy on fetal liver physiology. We used adenoviral gene delivery in Sprague-Dawley dams (seven females, 10 weeks old) during mid-gestation (gestational day 8) with adenovirus overexpressing sFlt-1, and age-matched controls (six females, 10 weeks old) with empty adenoviral virus in order to quantify the sFlt-1 concentrations in pregnant dams. Dams exposed to adenoviral sFlt-1 delivery were subdivided into a low (n=4) and high sFlt-1 (n=3) group based on host response to the virus. One-way analysis of variance showed that fetuses (five per dam) exposed to high sFlt-1 concentrations in utero show fetal growth restriction (1.84±0.043 g high sFlt-1 v. 2.32±0.036 g control; mean (M)±s.e.m.; P&lt;0.001), without hypertension or proteinuria in the dams. In continuation, the microarray analysis of the fetal liver of the high sFlt-1 group showed significant enrichment of key genes for fatty acid metabolism and Ppara targets. In addition, using pyrosequencing, we found that the Ppara enrichment in the high sFlt-1 group is accompanied by decreased methylation of its promoter (1.89±0.097 mean % methylation in high sFlt-1 v. 2.26±0.095 mean % methylation in control, M±s.e.m., P&lt;0.02). Our data show that high sFlt-1 concentrations during pregnancy have detrimental effects on the fatty acid metabolism genes and the Ppara targets in the fetal liver.

Cardiovascular Programming During and After Diabetic Pregnancy: Role of Placental Dysfunction and IUGR

Intrauterine growth restriction (IUGR) is a condition whereby a fetus is unable to achieve its genetically determined potential size. IUGR is a global health challenge due to high mortality and morbidity amongst affected neonates. It is a multifactorial condition caused by maternal, fetal, placental, and genetic confounders. Babies born of diabetic pregnancies are usually large for gestational age but under certain conditions whereby prolonged uncontrolled hyperglycemia leads to placental dysfunction, the outcome of the pregnancy is an intrauterine growth restricted fetus with clinical features of malnutrition. Placental dysfunction leads to undernutrition and hypoxia, which triggers gene modification in the developing fetus due to fetal adaptation to adverse utero environmental conditions. Thus, in utero gene modification results in future cardiovascular programming in postnatal and adult life. Ongoing research aims to broaden our understanding of the molecular mechanisms and pathological pathways involved in fetal programming due to IUGR. There is a need for the development of effective preventive and therapeutic strategies for the management of growth-restricted infants. Information on the mechanisms involved with in utero epigenetic modification leading to development of cardiovascular disease in adult life will increase our understanding and allow the identification of susceptible individuals as well as the design of targeted prevention strategies. This article aims to systematically review the latest molecular mechanisms involved in the pathogenesis of IUGR in cardiovascular programming. Animal models of IUGR that used nutrient restriction and hypoxia to mimic the clinical conditions in humans of reduced flow of nutrients and oxygen to the fetus will be discussed in terms of cardiac remodeling and epigenetic programming of cardiovascular disease. Experimental evidence of long-term fetal programming due to IUGR will also be included.

The Effect of Morbidity and Sex on Postnatal Growth of Very Preterm Infants: A Multicenter Cohort Study

BACKGROUND

Extrauterine growth restriction is common in the preterm infant, and it is associated with poor neurodevelopment. Nutrition plays an important role in postnatal growth, but growth is also influenced by other factors like co-morbidity, and, also, there might be sex differences.

METHODS

This is a cohort study including preterm infants < 32 weeks at birth (n = 21,825) from the Spanish Neonatal Network database. The effect of sex and morbidity (patent ductus arteriosus, bronchopulmonary dysplasia, necrotizing enterocolitis and late-onset sepsis) on weight gain as well as linear and head growth from birth to discharge/death was assessed with linear regression models adjusted by gestational age and Z-scores at birth.

RESULTS

The 4 selected morbidities had an independent effect on all 6 growth parameters studied, which was greater in the case of necrotizing enterocolitis: changes in weight, length and head Z-scores were -0.60 (95% CI: -0.66 to -0.55), -0.62 (95% CI: -0.70 to -0.54) and -0.63 (95% CI: -0.71 to -0.56), respectively. Weight gain and linear growth were overall more affected than head growth. Girls lost slightly more weight Z-scores (-0.03; 95% CI: -0.06 to -0.002) than boys after adjustment by morbidity. There were no significant gender differences regarding linear and head growth velocity (cm/week), although girls lost more head Z-scores (-0.14; 95% CI: -0.18 to -0.10).

CONCLUSIONS

Main co-morbidities associated with prematurity have an impact on postnatal growth. Head growth is less affected than length and weight. Girls are at slightly higher risk of postnatal weight and head restriction after adjustment by morbidity.

A prospective analysis of intake and composition of mother's own milk in preterm newborns less than 32 weeks' gestational age

Background Mothers of preterm (PT) infants have difficulty providing adequate quantities of human milk (HM) for their babies during their hospital stay. The macronutrient content in HM changes over time, varying across and within individual mothers. The research aim of the strudy was to describe the intake of mothers' own milk (MOM) and its composition according to gestational (GA) and postnatal age (PNA) in infants born <32 weeks' GA and to correlate them with neonatal weight, length and morbidities. Methods A prospective observational study of 176 premature infants in a unit without a donor milk bank was conducted. Daily milk intake was recorded. HM macronutrients were determined by mid-infrared spectrophotometric analysis at 7, 15 and 30 days after delivery and monthly until hospital discharge. Results Intake of MOM increased during the first 2 weeks after birth and decreased steadily thereafter. Protein concentration varied inversely with PNA. Carbohydrate and lipid concentrations increased over the first few days and remained stable thereafter. A fall in weight percentiles from birth to 60 days was found. No correlation was found between total protein and calorie intakes at 3 and 15 days of life and growth velocity (GV) between 15 and 30 days, even when broken down into parenteral nutrition (PN), formula and MOM. Conclusion To improve MOM feeding in PT newborns, intensive support strategies at the prenatal stage along entire hospitalization income should be encouraged. New protocols for fortification of HM should be implemented to optimize postnatal weight gain while preserving the health benefits of HM.

Placental MRI shows preservation of brain volume in growth-restricted fetuses who suffer substantial reduction of putative functional placenta tissue (PFPT)

OBJECTIVE

Recently, a potentially useful diagnostic approach based on MR diffusion-tensor-imaging (DTI) was reported for the estimation of putative functional placenta tissue (PFPT), thus providing direct information about placental function. Yet, the relation between reduced PFPT and the phenomenon of brain-sparing remains unclear. This study aimed to investigate the relation between brain-sparing and reduced PFPT volume, as found in fetuses with intrauterine growth restriction (IUGR).

METHODS

A total of 40 consecutive patients with a US-based diagnosis of placental IUGR were examined using fetal MRI. A control group of 78 patients who received fetal MRI, due to non-placental pathologies, was established. A somatic energy index was calculated as I_E=1-(V_brain/V_pfpt) from brain and PFPT volumes measured with DTI in both groups. I_E, V_pfpt, and V_brain were analyzed with respect to the gestational week.

RESULTS

V_brain corrected for gestational weeks was no different between both groups, while V_pfpt was significantly reduced in IUGR patients. I_E was significantly different between both groups and indicated a higher V_brain at a comparable V_pfpt.

CONCLUSIONS

Fetuses with IUGR show preserved energetic resources necessary for brain growth. Because I_E drops in IUGR more rapidly as pregnancy progresses, depending on V_pfpt, I_E could prove useful for estimating fetal well-being.

Neuropathology as a consequence of neonatal ventilation in premature growth-restricted lambs

Fetal growth restriction (FGR) and prematurity are associated with high risk of brain injury and long-term neurological deficits. FGR infants born preterm are commonly exposed to mechanical ventilation, but it is not known whether ventilation differentially induces brain pathology in FGR infants compared with appropriate for gestational age (AGA) infants. We investigated markers of neuropathology in moderate- to late-preterm FGR lambs, compared with AGA lambs, delivered by caesarean birth and ventilated under standard neonatal conditions for 24 h. FGR was induced by single umbilical artery ligation in fetal sheep at 88-day gestation (term, 150 days). At 125-day gestation, FGR and AGA lambs were delivered, dried, intubated, and commenced on noninjurious ventilation, with surfactant administration at 10 min. A group of unventilated FGR and AGA lambs at the same gestation was also examined. Over 24 h, circulating pH, Po₂, and lactate levels were similar between groups. Ventilated FGR lambs had lower cerebral blood flow compared with AGA lambs ( P = 0.01). The brain of ventilated FGR lambs showed neuropathology compared with unventilated FGR, and unventilated and ventilated AGA lambs, with increased apoptosis (caspase-3), blood-brain barrier dysfunction (albumin extravasation), activated microglia (Iba-1), and increased expression of cellular oxidative stress (4-hydroxynonenal). The neuropathologies seen in the ventilated FGR brain were most pronounced in the periventricular and subcortical white matter but also evident in the subventricular zone, cortical gray matter, and hippocampus. Ventilation of preterm FGR lambs increased brain injury compared with AGA preterm lambs and unventilated FGR lambs, mediated via increased vascular permeability, neuroinflammation and oxidative stress.

In vivo expansion of functionally integrated GABAergic interneurons by targeted increase in neural progenitors

A central hypothesis for brain evolution is that it might occur via expansion of progenitor cells and subsequent lineage-dependent formation of neural circuits. Here, we report in vivo amplification and functional integration of lineage-specific circuitry in Drosophila Levels of the cell fate determinant Prospero were attenuated in specific brain lineages within a range that expanded not only progenitors but also neuronal progeny, without tumor formation. Resulting supernumerary neural stem cells underwent normal functional transitions, progressed through the temporal patterning cascade, and generated progeny with molecular signatures matching source lineages. Fully differentiated supernumerary gamma-amino butyric acid (GABA)-ergic interneurons formed functional connections in the central complex of the adult brain, as revealed by in vivo calcium imaging and open-field behavioral analysis. Our results show that quantitative control of a single transcription factor is sufficient to tune neuron numbers and clonal circuitry, and provide molecular insight into a likely mechanism of brain evolution.

p53 is required for brain growth but is dispensable for resistance to nutrient restriction during Drosophila larval development

BACKGROUND

Animal growth is influenced by the genetic background and the environmental circumstances. How genes promote growth and coordinate adaptation to nutrient availability is still an open question. p53 is a transcription factor that commands the cellular response to different types of stresses. In adult Drosophila melanogaster, p53 regulates the metabolic adaptation to nutrient restriction that supports fly viability. Furthermore, the larval brain is protected from nutrient restriction in a phenomenon called 'brain sparing'. Therefore, we hypothesised that p53 may regulate brain growth and show a protective role over brain development under nutrient restriction.

RESULTS

Here, we studied the function of p53 during brain growth in normal conditions and in animals subjected to developmental nutrient restriction. We showed that p53 loss of function reduced animal growth and larval brain size. Endogenous p53 was expressed in larval neural stem cells, but its levels and activity were not affected by nutritional stress. Interestingly, p53 knockdown only in neural stem cells was sufficient to decrease larval brain growth. Finally, we showed that in p53 mutant larvae under nutrient restriction, the energy storage levels were not altered, and these larvae generated adults with brains of similar size than wild-type animals.

CONCLUSIONS

Using genetic approaches, we demonstrate that p53 is required for proper growth of the larval brain. This developmental role of p53 does not have an impact on animal resistance to nutritional stress since brain growth in p53 mutants under nutrient restriction is similar to control animals.

Maternal protein malnutrition: effects on prostate development and adult disease

Well-controlled intrauterine development is an essential condition for many aspects of normal adult physiology and health. This process is disrupted by poor maternal nutrition status during pregnancy. Indeed, physiological adaptations occur in the fetus to ensure nutrient supply to the most vital organs at the expense of the others, leading to irreversible consequences in tissue formation and differentiation. Evidence indicates that maternal undernutrition in early life promotes changes in key hormones, such as glucocorticoids, growth hormones, insulin-like growth factors, estrogens and androgens, during fetal development. These alterations can directly or indirectly affect hormone release, hormone receptor expression/distribution, cellular function or tissue organization, and impair tissue growth, differentiation and maturation to exert profound long-term effects on the offspring. Within the male reproductive system, maternal protein malnutrition alters development, structure, and function of the gonads, testes and prostate gland. Consequently, these changes impair the reproductive capacity of the male offspring. Further, permanent alterations in the prostate gland occur at the molecular and cellular level and thereby affect the onset of late life diseases such as prostatitis, hyperplasia and even prostate cancer. This review assembles current thoughts on the concepts and mechanisms behind the developmental origins of health and disease as they relate to protein malnutrition, and highlights the effects of maternal protein malnutrition on rat prostate development and homeostasis. Such insights on developmental trajectories of adult-onset prostate disease may help provide a foundation for future studies in this field.

Prevalence and Risk Factors for Microcephaly at Birth in Brazil in 2010

OBJECTIVES

To estimate the baseline prevalence and risk factors for microcephaly at birth before the Zika virus epidemic in 2 Brazilian cities.

METHODS

We used population-based data from the Brazilian Ribeirão Preto (RP) and São Luís (SL) birth cohort studies of 2010 that included hospital deliveries by resident mothers. The final sample was 7376 live births in RP and 4220 in SL. Gestational age was based on the date of the mother's last normal menstrual period or obstetric ultrasonography, if available. Microcephaly at birth was classified according to the criteria of the International Fetal and Newborn Growth Consortium for the 21st Century and the Brazilian Ministry of Health. Risk factors for microcephaly, proportionate and disproportionate microcephaly, and severe microcephaly were estimated in a hierarchized logistic regression model.

RESULTS

According to the International Fetal and Newborn Growth Consortium for the 21st Century definition, the prevalence of microcephaly (>2 SDs below the mean for gestational age and sex) was higher in SL (3.5%) than in RP (2.5%). The prevalence of severe microcephaly (>3 SDs below the mean) was higher in SL (0.7%) than in RP (0.5%). Low maternal schooling, living in consensual union or without a companion, maternal smoking during pregnancy, primiparity, vaginal delivery, and intrauterine growth restriction were consistently associated with microcephaly. The number of cases of microcephaly is grossly underestimated, with an underreporting rate of ∼90%.

CONCLUSIONS

The prevalence of severe microcephaly was much higher than expected in both cities. Our findings suggest that microcephaly was endemic in both municipalities before the circulation of the Zika virus.

Antenatal glucocorticoids, magnesium sulfate, and mode of birth in preterm fetal small for gestational age

A diagnosis of fetal growth restriction and subsequent preterm birth is associated with increased risks of adverse perinatal and neurodevelopmental outcomes and potentially long-lasting effects to adulthood. Most such cases are associated with placental insufficiency and the fetal response to chronic intrauterine hypoxemia and nutrient deprivation leads to substantial physiological and metabolic adaptations. The management of such pregnancies, especially with respect to perinatal interventions and birth mode, remains an unresolved dilemma. The benefits from standard interventions for threatened preterm birth may not be necessarily translated to pregnancies with small-for-gestational-age fetuses. Clinical trials or retrospective studies on outcomes following administration of antenatal glucocorticoids and magnesium sulfate for neuroprotection when preterm birth is imminent either have yielded conflicting results for small-for-gestational-age fetuses, or did not include this subgroup of patients. Experimental models highlight potential harmful effects of administration of antenatal glucocorticoids and magnesium sulfate in the pregnancies with fetal small for gestational age although clinical data do not substantiate these concerns. In addition, heterogeneity in definitions of fetal small for gestational age, variations in the inclusion criteria, and the glucocorticoid regime contribute to inconsistent results. In this review, we discuss the physiologic adaptions of the small-for-gestational-age fetus to its abnormal in utero environment in relation to antenatal glucocorticoids; the impact of antenatal glucocorticoids and intrapartum magnesium sulfate in pregnancies with fetal small for gestational age; the current literature on birth mode for pregnancies with fetal small for gestational age; and the knowledge gaps in the existing literature.

In vivo assessment of placental and brain volumes in growth-restricted fetuses with and without fetal Doppler changes using quantitative 3D MRI

OBJECTIVE

The relationship between placental and fetal brain growth is poorly understood and difficult to assess. The objective of this study was to interrogate placental and fetal brain growth in healthy pregnancies and those complicated by fetal growth restriction (FGR).

STUDY DESIGN

In a prospective, observational study, pregnant women with normal pregnancies or pregnancies complicated by FGR underwent fetal magnetic resonance imaging (MRI). Placental, global and regional brain volumes were calculated.

RESULTS

A total of 114 women (79 controls and 35 FGR) underwent MRI (median gestational age (GA) 30 weeks, range 18 to 39). All measured volumes increased exponentially with advancing GA. Placental, total brain, cerebral and cerebellar volumes were smaller in FGR compared with controls (P<0.05). Increasing placental volume was associated with increasing cerebral and cerebellar volumes (P<0.05).

CONCLUSION

Quantitative fetal MRI can accurately detect decreased placental and brain volumes in pregnancies with FGR and may provide insight into the timing and mechanisms of brain injury in FGR.

Cognitive Functioning and Academic Achievement in Children Aged 6-8 Years, Born at Term After Intrauterine Growth Restriction and Fetal Cerebral Redistribution

Objective

To determine whether cerebroplacental ratio, an indicator of fetal cerebral redistribution (FCR), predicts adverse results for neurodevelopment in intrauterine growth restriction (IUGR) infants.

Methods

In a cohort of 5,702 infants, 64 were IUGR born at term with FCR. Five were excluded. Of the remainder, 32 presented an abnormal cerebroplacental ratio (IUGR-A) and 27 a normal one (IUGR-B). The controls were 61 appropriate-for-gestational-age children. Cognitive and academic outcomes and the odds ratio of lower academic scores were assessed by multivariate analysis of covariance and logistic regression.

Results

IUGR-A children presented deficits in cognitive functioning and academic achievement in all domains. IUGR-B children presented slight deficits. Suboptimal cognitive functioning in IUGR-A was more marked in working memory. Abnormal cerebroplacental ratio predicted low academic scores in IUGR-A.

Conclusions

FCR is a risk factor for IUGR infants, and cerebroplacental ratio identifies those most severely affected. Intervention programs may produce benefits in early-middle childhood.

Fetal-growth-restricted preterm infants display compromised autonomic cardiovascular control on the first postnatal day but not during infancy

BackgroundFetal growth restriction (FGR) is associated with increased perinatal mortality and long-term cardiovascular and neurodevelopmental sequelae. We hypothesized that FGR impacts on the development of autonomic heart rate and blood pressure control, contributing to unfavorable short- and long-term outcomes following FGR.MethodsWe studied 25 preterm FGR and 22 preterm and 19 term appropriate for gestational age (AGA) infants. Preterm neonates were studied on postnatal day 1, and all infants were studied at 1 and 6 months post-term age. To investigate autonomic cardiovascular control, we examined heart rate variability (HRV) and baroreflex sensitivity using spectral power and transfer-function analyses.ResultsPreterm FGR neonates exhibited higher heart rates and reduced HRV compared with preterm AGA controls on postnatal day 1. No significant differences were found between the three groups at 1 or 6 months post-term age.ConclusionPreterm FGR neonates display compromised HRV on postnatal day 1, which may suggest increased vulnerability to circulatory instability. This may predispose these neonates to systemic and cerebral hypoperfusion and increase the risk of long-term neurodevelopmental sequelae. Differences were no longer found at 1 and 6 months post-term age, suggesting that the maturation of autonomic cardiovascular control may be preserved following FGR.

Diffusion-weighted magnetic resonance imaging of the fetal brain in intrauterine growth restriction

OBJECTIVE

Diffusion-weighted magnetic resonance imaging (DWI) is a sensitive method for assessing brain maturation and detecting brain lesions, providing apparent diffusion coefficient (ADC) values as a measure of water diffusion. Abnormal ADC values are seen in ischemic brain lesions, such as those associated with acute or chronic hypoxia. The aim of this study was to assess whether ADC values in the fetal brain were different in fetuses with severe intrauterine growth restriction (IUGR) compared with normal controls.

METHODS

Brain magnetic resonance imaging (MRI) with single-shot axial DWI (b = 0 and b = 700 s/mm² ) was performed in 30 fetuses with severe IUGR (estimated fetal weight < 3^rd centile with absent or reversed umbilical artery Doppler flow) and in 24 normal controls of similar gestational age. Brain morphology and biometry were analyzed. ADC values were measured in frontal and occipital white matter, centrum semiovale, thalami, cerebellar hemisphere and pons. Frontal-occipital and frontal-cerebellar ADC ratios were calculated, and values were compared between IUGR fetuses and controls.

RESULTS

There was no difference in gestational age at MRI between IUGR and control fetuses (IUGR, 30.2 ± 1.6 weeks vs controls, 30.7 ± 1.4 weeks). Fetal brain morphology and signals were normal in all fetuses. Brain dimensions (supratentorial ± infratentorial) were decreased (Z-score, < -2) in 20 (66.7%) IUGR fetuses. Compared with controls, IUGR fetuses had significantly lower ADC values in frontal white matter (1.97 ± 0.23 vs 2.17 ± 0.22 × 10^-3 mm² /s; P < 0.0001), thalami (1.04 ± 0.15 vs 1.13 ± 0.10 ×10^-3 mm² /s; P = 0.0002), centrum semiovale (1.86 ± 0.22 vs 1.97 ± 0.23 ×10^-3 mm² /s; P = 0.01) and pons (0.85 ± 0.19 vs 0.94 ± 0.12 ×10^-3 mm² /s; P = 0.043). IUGR fetuses had a lower frontal-occipital ADC ratio than did normal fetuses (1.00 ± 0.11 vs 1.08 ± 0.05; P = 0.003).

CONCLUSIONS

ADC values in IUGR fetuses were significantly lower than in normal controls in the frontal white matter, thalami, centrum semiovale and pons, suggesting abnormal maturation in these regions. However, the prognostic value of these ADC changes is still unknown. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.

Color doppler indices of proximal and distal parts of middle cerebral artery in fetuses with intrauterine growth restriction

INTRODUCTION

Intrauterine growth restriction (IUGR) is a major clinical issue for pregnant women. The purpose of this study was to evaluate color Doppler indices of the proximal and distal parts of the middle cerebral artery (MCA) of the fetus.

METHODS

In this cross-sectional study, 350 pregnant patients, with gestation age of 32-40 who were suspected to have intrauterine growth restriction, participated. The patients were referred for color Doppler sonography at the Imam Reza Hospital (Kermanshah, Iran) from May 2011 to September 2012. The following indices were measured for the proximal and distal part of the MCA: pulsatility index (PI), resistive index (RI), fetal heart rate (FHR), systolic to diastolic (S/D) ratio, and peak systolic velocity (PSV). The data were analyzed applying Tukey's-test, Paired-Samples t-test, and simple linear regression analysis using SPSS 19.

RESULTS

Average age of the mother, the frequency of pregnancy, and fetus gestational age were 27.79±0.17 years, 2.09±1.3, and 34.19±2.52 weeks, respectively. For gestation age of <36weeks, all Doppler indices of the distal part of the fetus MCA were significantly different from those of proximal part (p<0.05). Comparing indices of gestation age <36 weeks with those of >36 weeks, significant difference was found between the Doppler indices of the proximal parts as well as for the distal parts (p<0.05).

CONCLUSION

Measurement of fetus MCA indices may depend to the sampling location; however, this needs further investigation in order to find a clear probe location.

A case of giant vein of Galen malformation resulting in severe IUGR

Vein of Galen aneurysmal malformation (VGAM) is a rare congenital vascular malformation. We describe a unique case of VGAM diagnosed antenatally due to severe intrauterine growth restriction (IUGR) and heart failure. The neonate underwent two transarterial interventional embolization procedures on days 1 and 4 due to developing ventricular dilation and worsening cardiac failure. We emphazise the importance of a prenatal brain color-Doppler study in all cases of IUGR and the importance of tertiary center referral for a multidisciplinary team approach. Early embolization should be considered in the presence of antenatal heart failure, aiming to limit the neurological sequelae and the multiorgan failure.

Competition for Materno-Fetal Resource Partitioning in a Rabbit Model of Undernourished Pregnancy

The major goal of animal production is to obtain abundant and healthy meat for consumers. Maternal food restriction (MFR) is often applied in farms to reduce production costs. However, the suitability of MFR in livestock animals is questionable, as this management may compromise maternal fitness due to a severe negative energetic balance and can induce Intrauterine Growth Restriction (IUGR) and prenatal programming in the offspring. Here, we sought to determine, using pregnant rabbits, the consequences of MFR on maternal endocrine and metabolic status and conceptus development. Pregnant dams were distributed into three groups: CONTROL (ad libitum feeding throughout the entire pregnancy; mean pregnancy length being around 31 days), UNDERFED (50% MFR during the entire pregnancy) and EARLY-UNDERFED (50% MFR only during the preimplantation period, Days 0–7). Maternal leptin concentrations and glycemic and lipid profiles were determined throughout pregnancy, whilst conceptus development was assessed ex-vivo at Day 28. Placental parameters were determined by macroscopic and histological evaluations and apoptotic assessments (TUNEL and Caspase-3). The main results of the study showed that, despite MFR altered maternal plasma lipid concentration (P<0.05), there were no effects on maternal bodyweight, plasma leptin concentration or glycemic profile. Fetal crown-rump lengths were reduced in both undernourished groups (P<0.001), but a significant reduction in fetal weight was only observed in the UNDERFED group (P<0.001). Growth in both undernourished groups was asymmetrical, with reduced liver weight (P<0.001) and significantly increased brain: fetal weight-ratio (P<0.001) and brain: liver weight-ratio (P<0.001) when compared to the CONTROL group. A significant reduction in placental weight was only observed in the UNDERFED group (P<0.001), despite both undernourished groups showing higher apoptotic rates at decidua and labyrinth zone (P<0.05) than the CONTROL group. Thus, these groups evidenced signs of placental degeneration, necrosis and stromal collapse. In summary, MFR may encourage the mother to make strategic decisions to safeguard her metabolic status and fitness at the expense of growth reduction in the litter, resulting in enhanced apoptotic and pathological processes at placental level and IUGR.

Reduction in Cerebral Oxygenation due to Patent Ductus Arteriosus Is Pronounced in Small-for-Gestational-Age Neonates

BACKGROUND

A haemodynamically significant patent ductus arteriosus (hsPDA) reduces cerebral oxygenation in appropriate-for-gestational-age (AGA) preterm neonates. Reduced cerebral oxygenation has been associated with brain injury. Preterm small-for-gestational-age (SGA) neonates show higher cerebral oxygenation than AGA peers throughout the first postnatal days. To date, no studies have investigated the effect of hsPDA on cerebral oxygenation in preterm SGA neonates.

OBJECTIVE

We aimed to assess the effect of hsPDA on cerebral oxygenation in preterm SGA neonates compared to AGA peers. We hypothesised that higher baseline cerebral oxygenation would reduce the impact of hsPDA on cerebral oxygenation in preterm SGA neonates.

METHODS

We monitored regional cerebral oxygen saturation (rScO2) with near-infrared spectroscopy and calculated the cerebral fractional tissue oxygen extraction (cFTOE) for 72 h after birth. Retrospective analysis compared 36 preterm SGA neonates (birth weight <10th percentile, 18 with hsPDA) to 36 preterm AGA neonates (birth weight 20th to 80th percentile, 18 with hsPDA).

RESULTS

In contrast to the other groups, SGA-hsPDA neonates demonstrated a significant fall in rScO2 [69% (SEM 2.5) at 4-8 h to 61% (2.7) at 68-72 h, p < 0.001] with a concurrent rise in cFTOE [0.26 (0.026) at 4-8 h to 0.34 (0.030) at 68-72 h, p < 0.001].

CONCLUSIONS

Contrary to our hypothesis, hsPDA had a significant negative effect on cerebral oxygenation in preterm SGA neonates. Future studies should explore the potential benefits of early screening and treatment for hsPDA on long-term neurodevelopmental outcome in preterm SGA neonates.

Review: Neuroinflammation in intrauterine growth restriction

Disruption to the maternal environment during pregnancy from events such as hypoxia, stress, toxins, inflammation, and reduced placental blood flow can affect fetal development. Intrauterine growth restriction (IUGR) is commonly caused by chronic placental insufficiency, interrupting supply of oxygen and nutrients to the fetus resulting in abnormal fetal growth. IUGR is a major cause of perinatal morbidity and mortality, occurring in approximately 5-10% of pregnancies. The fetal brain is particularly vulnerable in IUGR and there is an increased risk of long-term neurological disorders including cerebral palsy, epilepsy, learning difficulties, behavioural difficulties and psychiatric diagnoses. Few studies have focused on how growth restriction interferes with normal brain development in the IUGR neonate but recent studies in growth restricted animal models demonstrate increased neuroinflammation. This review describes the role of neuroinflammation in the progression of brain injury in growth restricted neonates. Identifying the mediators responsible for alterations in brain development in the IUGR infant is key to prevention and treatment of brain injury in these infants.