Neurodevelopment after fetal growth restriction

Insights into neurosonographic indicators for prenatal diagnosis of fetal neurological anomalies and cortical development: A systematic review of the literature

BACKGROUND

Congenital defects of the central nervous system are the second cause of disability in childhood, representing up to 20 % of structural malformations diagnosed prenatally. The accurate prenatal diagnosis of fetal neurological anomalies and the assessment of cortical development are critical for early intervention and improved long-term outcomes. Neurosonography plays a vital role in this process, providing detailed insights into the structural and functional development of the fetal brain. This systematic review aims to synthesize current knowledge on neurosonographic indicators for prenatal diagnosis, with a special focus on cortical development and its impact in cases of fetal growth defects.

MATERIAL AND METHODS

We conducted a comprehensive search for primary literature in PubMed database were searched for English and Spanish-language, peer-reviewed literature published in the last 15 years. Additional articles were identified by scrutinizing others search platforms (Cochrane Library, UpToDate). Inclusion criteria were single pregnancy and no known feto-maternal pathologies at the beginning of the study.

RESULTS

Of the 361 published abstracts identified, 35 met criteria for inclusion. The review highlighted the importance of detailed neurosonographic assessments, including the evaluation of cerebral fissures such as the Sylvian fissure, parieto-occipital fissure, and calcarine fissure. Targeted ultrasound techniques were found to provide comprehensive insights comparable to fetal magnetic resonance imaging. We underscored the significant impact of intrauterine growth restriction on cortical development, with early intervention being crucial. Genetic and congenital infection screenings were emphasized as essential components of prenatal assessment.

CONCLUSION

The assessment of fetal brain maturation patterns according to gestational age allows us to rule out a delay in cortical development. The heterogeneity of methods and evaluable parameters in fetal neurodevelopment makes it necessary to standardize the evaluation of the main structures of interest both for screening and for the diagnosis of cortical development anomalies, even with the aim of trying to improve upgrade prognostic advice.

Adverse neurodevelopment in children associated with prenatal exposure to fine particulate matter (PM2.5) - Possible roles of polycyclic aromatic hydrocarbons (PAHs) and mechanisms involved

Prenatal exposure to ambient fine particles (PM2.5) and polycyclic aromatic hydrocarbons (PAHs) has been associated with adverse birth outcomes including neurodevelopmental effects with cognitive and/or behavioral implications in early childhood. As a background we first briefly summarize human studies on PM2.5 and PAHs associated with adverse birth outcomes and modified neurodevelopment. Next, we add more specific information from animal studies and in vitro studies and elucidate possible biological mechanisms. More specifically we focus on the potential role of PAHs attached to PM2.5 and explore whether effects of these compounds may arise from disturbance of placental function or more directly by interfering with neurodevelopmental processes in the fetal brain. Possible molecular initiating events (MIEs) include interactions with cellular receptors such as the aryl hydrocarbon receptor (AhR), beta-adrenergic receptors (βAR) and transient receptor potential (TRP)-channels resulting in altered gene expression. MIE linked to the binding of PAHs to cytochrome P450 (CYP) enzymes and formation of reactive electrophilic metabolites are likely less important. The experimental animal and in vitro studies support the epidemiological findings and suggest steps involved in mechanistic pathways explaining the associations. An overall evaluation of the doses/concentrations used in experimental studies combined with the mechanistic understanding further supports the hypothesis that prenatal PAHs exposure may cause adverse outcomes (AOs) linked to human neurodevelopment. Several MIEs will likely occur simultaneously in various cells/tissues involving several key events (KEs) which relative importance will depend on dose, time, tissue, genetics, other environmental factors, and neurodevelopmental endpoint in study.

Does Catch-Up Growth Come with a Cognitive Cost? Cognitive Outcome and Growth Patterns in Growth Discordant Identical Twins

OBJECTIVE

To determine whether it is the magnitude of early postnatal catch-up growth (CUG) in response to fetal growth restriction (FGR) or the FGR itself that negatively impacts cognitive outcome in a model of monochorionic twins discordant for fetal growth.

STUDY DESIGN

This analysis is part of the LEMON study, a cohort study including all monochorionic twins with selective FGR aged 3 through 17 years. Growth measurements as documented by our primary care system were collected retrospectively. An age-appropriate neurodevelopmental test was performed generating a full-scale IQ (FSIQ). CUG at 2 years was calculated as (weight [kg] at 2 years-birth weight [kg]). We used a multivariable regression model investigating the association between FSIQ (outcome) and birth weight zscore, gestational age at birth and CUG at 2 years (predictors). Generalized estimating equations accounted for the fact that observations between cotwins are not independent.

RESULTS

Median age at follow-up of the 46 included twin pairs was 11 (IQR 8-13) years. Birth weight z score and gestational age at birth were significantly associated with FSIQ, with β-coefficients of 5.897 (95% CI 3.382-8.411), and 2.589 (95% CI 1.227-3.951), respectively (P < .0001). Adjusted for birth weight z score and gestational age, CUG in the first 2 years after birth was not significantly associated with FSIQ (β-coefficient 0.108 [95% CI -1.373 to 1.590], P = .886).

CONCLUSIONS

Our results, combining detailed growth measurements and neurodevelopmental follow-up in a discordant identical twin model, demonstrate that FGR itself rather than early postnatal CUG has negative consequences for cognitive development.

Diagnosis, Prevention, and Management of Fetal Growth Restriction (FGR)

Fetal growth restriction (FGR), or intrauterine growth restriction (IUGR), is still the second most common cause of perinatal mortality. The factors that contribute to fetal growth restriction can be categorized into three distinct groups: placental, fetal, and maternal. The prenatal application of various diagnostic methods can, in many cases, detect the deterioration of the fetal condition in time because the nature of the above disorder is thoroughly investigated by applying a combination of biophysical and biochemical methods, which determine the state of the embryo-placenta unit and assess the possible increased risk of perinatal failure outcome and potential for many later health problems. When considering the potential for therapeutic intervention, the key question is whether it can be utilized during pregnancy. Currently, there are no known treatment interventions that effectively enhance placental function and promote fetal weight development. Nevertheless, in cases with fetuses diagnosed with fetal growth restriction, immediate termination of pregnancy may have advantages not only in terms of minimizing perinatal mortality but primarily in terms of reducing long-term morbidity during childhood and maturity.

Machine learning analysis with population data for prepregnancy and perinatal risk factors for the neurodevelopmental delay of offspring

Neurodevelopmental disorders (NDD) in offspring are associated with a complex combination of pre-and postnatal factors. This study uses machine learning and population data to evaluate the association between prepregnancy or perinatal risk factors and the NDD of offspring. Population-based retrospective cohort data were obtained from Korea National Health Insurance Service claims data for 209,424 singleton offspring and their mothers who gave birth for the first time in 2007. The dependent variables were motor development disorder (MDD), cognitive development disorder (CDD) and combined overall neurodevelopmental disorder (NDD) from offspring. Seventeen independent variables from 2002 to 2007 were included. Random forest variable importance and Shapley Additive Explanation (SHAP) values were calculated to analyze the directions of its associations with the predictors. The random forest with oversampling registered much higher areas under the receiver-operating-characteristic curves than the logistic regression of interaction and non-linearity terms, 79% versus 50% (MDD), 82% versus 52% (CDD) and 74% versus 50% (NDD). Based on random forest variable importance, low socioeconomic status and age at birth were highly ranked. In SHAP values, there was a positive association between NDD and pre- or perinatal outcomes, especially, fetal male sex with growth restriction associated the development of NDD in offspring.

Evaluation of the type of fetal umblical-portal anastomosis in late-onset fetal growth restriction: A case-control study

PURPOSE

To evaluate the type of umbilical-portal anastomosis in late-onset fetal growth restriction (LO-FGR) and appropriate for gestational age (AGA) fetuses. To investigate the impact of the type of umbilical-portal anastomosis on the adverse outcomes in LO-FGR.

METHOD

This study observed 150 pregnancies with AGA fetuses and 62 pregnancies with fetuses with LO-FGR. In each case, the point of reference for measuring the abdominal circumference was established. The type of umbilical-portal anastomosis was evaluated as T-shaped, X-shaped, and H-shaped according to the shape of main portal vein and portal sinus. Incidences of the type of umbilical-portal anastomosis in AGA and LO-FGR fetuses were evaluated.

RESULTS

T-shaped anastomosis was the most common (56.7%) in the AGA group and X-shaped (66.1%) in the LO-FGR group. In LO-FGR, T-shape anastomosis was significantly lower and X-shape anastomosis was significantly higher than AGA (p < 0.001). X-shaped anastomosis was associated with LO-FGR and the RR was 2.3 (95% CI 1.5-3.6; p < 0.001). Incidences of admission to NICU and emergency C/S for fetal distress were higher in fetuses with X -shaped anastomosis in the LO-FGR (p < 0.05).

CONCLUSION

X-shaped umbilical-portal anastomosis have a prognostic significance in LO-FGR fetuses.

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.

Tadalafil for Treatment of Fetal Growth Restriction: A Review of Experimental and Clinical Studies

Fetal growth restriction (FGR) is a major concern in perinatal care. Various medications have been proposed as potential treatments for this serious condition. Nonetheless, there is still no definitive treatment. We studied tadalafil, a phosphodiesterase-5 inhibitor, as a therapeutic agent for FGR in clinical studies and animal experiments. In this review, we summarize our preclinical and clinical data on the use of tadalafil for FGR. Our studies in mouse models indicated that tadalafil improved FGR and hypertensive disorders of pregnancy. A phase II trial we conducted provided evidence supporting the efficacy of tadalafil in prolonging pregnancy (52.4 vs. 36.8 days; p = 0.03) and indicated a good safety profile for fetuses and neonates. Fetal, neonatal, and infant mortality was significantly lower in mothers receiving tadalafil treatment than that in controls (total number: 1 vs. 7, respectively; p = 0.03), and no severe adverse maternal events associated with tadalafil were observed. Although further studies are needed to establish the usefulness of tadalafil in FGR treatment, our research indicates that the use of tadalafil in FGR treatment may be a paradigm shift in perinatal care.

Fetal growth assessed via ultrasound in relation to maternal HIV infection status and antiretroviral regimens

OBJECTIVE

To evaluate effects of maternal HIV and antiretroviral treatment (ART) on intrauterine fetal growth.

DESIGN

Prospective cohort studies of HIV and ZIKA infection among women living with HIV (WLHIV) and women not living with HIV (WNLHIV) conducted in Brazil and the US from 2016 to 2020.

METHODS

We evaluated fetal growth via repeated ultrasounds and calculated z scores for fetal growth measures using Intergrowth-21st standards among women with singleton pregnancies. Adjusted linear mixed models were fit for each fetal growth z score by HIV status. Among WLHIV, we compared fetal growth z scores by the most common maternal ART regimens, stratified by timing of ART initiation.

RESULTS

We included 166 WLHIV and 705 WNLHIV; none had Zika infection. The z scores were similar for WLHIV and WNLHIV for femur length (latest third trimester median = 1.08) and estimated fetal weight (median ≈0.60); adjusted mean differences in fetal weight z scores by HIV status were less than 0.1 throughout gestation. Other fetal growth measurements were lower for WLHIV than WNLHIV early in gestation but increased more rapidly over gestation. Among WLHIV not on ART at conception, adjusted mean z scores were generally similar across regimens initiated during pregnancy but somewhat lower for atazanavir-based regimens for biparietal diameter compared with efavirenz-based or raltegravir-based regimens. Among WLHIV on ART at conception, mean z scores were similar across ART regimens.

CONCLUSION

Within our cohorts, fetal growth was lower in WLHIV than WNLHIV early in gestation but similar by the end of gestation, which is reassuring. Among WLHIV, fetal growth measures were generally similar across ART regimens evaluated.

Corpus Callosum Length and Cerebellar Vermian Height in Fetal Growth Restriction

INTRODUCTION

Growth-restricted fetuses may have changes in their neuroanatomical structures that can be detected in prenatal imaging. We aim to compare corpus callosal length (CCL) and cerebellar vermian height (CVH) measurements between fetal growth restriction (FGR) and control fetuses and to correlate them with cerebral Doppler velocimetry in growth-restricted fetuses.

METHODS

This was a prospective cohort of FGR after 20 weeks of gestation with ultrasound measurements of CCL and CVH. Control cohort was assembled from fetuses without FGR who had growth ultrasound after 20 weeks of gestation. We compared differences of CCL or CVH between FGR and controls. We also tested for the correlations of CCL and CVH with middle cerebral artery (MCA) pulsatility index (PI) and vertebral artery (VA) PI in the FGR group. CCL and CVH measurements were adjusted by head circumference (HC).

RESULTS

CCL and CVH were obtained in 68 and 55 fetuses, respectively. CCL/HC was smaller in FGR fetuses when compared to control fetuses (difference = 0.03, 95% CI: [0.02, 0.04], p < 0.001). CVH/HC was larger in FGR fetuses compared to NG fetuses (difference = 0.1, 95% CI: [-0.01, 0.02], p = < 0.001). VA PI multiples of the median were inversely correlated with CVH/HC (rho = -0.53, p = 0.007), while CCL/HC was not correlated with VA PI. Neither CCL/HC nor CVH/HC was correlated with MCA PI.

CONCLUSIONS

CCL/HC and CVH/HC measurements show differences in growth-restricted fetuses compared to a control cohort. We also found an inverse relationship between VA PI and CVH/HC. The potential use of neurosonography assessment in FGR assessment requires continued explorations.

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.

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.

Impact of early-onset fetal growth restriction on the neurodevelopmental outcome of very preterm infants at 24 months: a retrospective cohort study

BACKGROUND

The association between fetal growth restriction (FGR) and childhood neurodevelopmental delay is unclear and the evidence available to the present date shows conflicting results. Our aim was to analyse the impact of early-onset FGR on the neurodevelopmental outcome at 24 months of corrected age in very preterm infants.

METHODS

Retrospective cohort study of very preterm infants (≤ 32 weeks' gestation) admitted to a neonatal intensive care unit between 1 January 2013-31 December 2019. The control group comprised appropriate for gestational age (AGA) newborns. Griffiths III Mental Development Scale was performed at 24 months of corrected age.

RESULTS

132 infants were included: 44 FGR and 88 AGA. Mean Global Development Quotient (GDQ) was lower for FGR infants (p = 0.004) even after adjusting for maternal and perinatal factors (βadjusted -16.703; p = 0.009). The average scores for the neurodevelopmental domains were highest for personal-social-emotional skills (107.02 ± 16.34), followed by eye/hand coordination (105.61 ± 14.20) and foundation of learning skills (102.23 ± 13.74) and were lowest for gross motor (97.90 ± 11.88) and language/communication skills (96.39 ± 18.88). FGR had a significant negative impact on all domains except for gross motor skills. After adjustment, FGR continued to have a significant adverse impact on language/communication (βadjusted -21.924; p = 0.013), eye/hand coordination (βadjusted -15.446; p = 0.015) and foundation of learning skills (βadjusted -15.211; p = 0.013).

CONCLUSIONS

In very preterm infants, FGR was associated with a significantly increased risk of poor neurodevelopmental outcome at 24 months of corrected age compared to age-matched AGA infants.

Fetal growth restriction inhibits childhood growth despite catch-up in discordant identical twins: an observational cohort study

OBJECTIVE

Research suggests that postnatal catch-up growth after fetal growth restriction (FGR) occurs frequently. Yet, postnatal growth in singletons may be influenced by multiple factors. Identical twins with discordant prenatal growth, termed selective FGR (sFGR), can be regarded as a natural experiment eliminating these sources of bias.

DESIGN

Observational cohort study.

METHODS

Monochorionic twins with sFGR born between 2002 and 2017 (aged 3-17 years) were eligible. Growth measurements (height, weight, head circumference, and body mass index) were performed at follow-up. Detailed growth curves documented by a systematic primary care system in the Netherlands were collected. Measurements were converted to standard deviation scores (SDSs). A mixed-effects model was used to assess within-pair SDS difference and individual height SDS relative to target height SDS.

RESULTS

Forty-seven twin pairs (94 children) were included at a median age of 11 (interquartile range 8-13) years. At the last measurement, smaller twins at birth had a lower height SDS [-0.6 vs -0.3, P < .001, median difference 0.5 (95%CI 0.4-0.7)], lower weight SDS [-0.5 vs -0.1, P < .001, median difference 0.8 (95%CI 0.5-1.0)], and lower head circumference SDS [-0.5 vs 0.2, P < .001, median difference 0.8 (95%CI 0.6-0.9)] compared to larger twins. These differences persisted until the age of 17. Smaller twins showed rapid catch-up growth in the first 2 years and reached their target height range between 8 and 11 years.

CONCLUSIONS

Identical twins with discordant prenatal growth maintain a modest but significant difference in height, weight, and head circumference, indicating a persistent, inhibitory effect of an adverse intrauterine environment on childhood growth.

Relationship between Abnormal Placenta and Obstetric Outcomes: A Meta-Analysis

The placenta has several crucial physiological functions that help maintain a normal pregnancy. Although approximately 2-4% of pregnancies are complicated by abnormal placentas, obstetric outcomes remain understudied. This study aimed to determine the outcomes and prevalence of patients with abnormal placentas by conducting a systematic review of 48 studies published between 1974 and 2022. The cumulative prevalence of circumvallate placenta, succenturiate placenta, multilobed placenta, and placenta membranacea were 1.2%, 1.0%, 0.2%, and 0.004%, respectively. Pregnancies with a circumvallate placenta were associated with an increased rate of emergent cesarean delivery, preterm birth (PTB), and placental abruption compared to those without a circumvallate placenta. The succenturiate lobe of the placenta was associated with a higher rate of emergent cesarean delivery, whereas comparative results were observed in terms of PTB, placental abruption, and placenta previa in comparison to those without a succenturiate lobe of the placenta. A comparator study that examined the outcomes of multilobed placentas found that this data is usually unavailable. Patient-level analysis (n = 15) showed high-rates of abortion (40%), placenta accreta spectrum (40%), and a low term delivery rate (13.3%) in women with placenta membranacea. Although the current evidence is insufficient to draw a robust conclusion, abnormal placentas should be recognized as a high-risk factor for adverse outcomes during pregnancy.

Improving birth weight measurement and recording practices in Kenya and Tanzania: a prospective intervention study with historical controls

BACKGROUND

Low birth weight (LBW) is a significant public health concern given its association with early-life mortality and other adverse health consequences that can impact the entire life cycle. In many countries, accurate estimates of LBW prevalence are lacking due to inaccuracies in collection and gaps in available data. Our study aimed to determine LBW prevalence among facility-born infants in selected areas of Kenya and Tanzania and to assess whether the introduction of an intervention to improve the accuracy of birth weight measurement would result in a meaningfully different estimate of LBW prevalence than current practice.

METHODS

We carried out a historically controlled intervention study in 22 health facilities in Kenya and three health facilities in Tanzania. The intervention included: provision of high-quality digital scales, training of nursing staff on accurate birth weight measurement, recording and scale calibration practices, and quality maintenance support that consisted of enhanced supervision and feedback (prospective arm). The historically controlled data were birth weights from the same facilities recorded in maternity registers for the same calendar months from the previous year measured using routine practices and manual scales. We calculated mean birth weight (95% confidence interval CI), mean difference in LBW prevalence, and respective risk ratio (95% CI) between study arms.

RESULTS

Between October 2019 and February 2020, we prospectively collected birth weights from 8441 newborns in Kenya and 4294 in Tanzania. Historical data were available from 9318 newborns in Kenya and 12,007 in Tanzania. In the prospective sample, the prevalence of LBW was 12.6% (95% confidence intervals [CI]: 10.9%-14.4%) in Kenya and 18.2% (12.2%-24.2%) in Tanzania. In the historical sample, the corresponding prevalence estimates were 7.8% (6.5%-9.2%) and 10.0% (8.6%-11.4%). Compared to the retrospective sample, the LBW prevalence in the prospective sample was 4.8% points (3.2%-6.4%) higher in Kenya and 8.2% points (2.3%-14.0%) higher in Tanzania, corresponding to a risk ratio of 1.61 (1.38-1.88) in Kenya and 1.81 (1.30-2.52) in Tanzania.

CONCLUSION

Routine birth weight records underestimate the risk of LBW among facility-born infants in Kenya and Tanzania. The quality of birth weight data can be improved by a simple intervention consisting of provision of digital scales and supportive training.

Blood Biomarkers in the Fetally Growth Restricted and Small for Gestational Age Neonate: Associations with Brain Injury

Fetal growth restriction (FGR) and small for gestational age (SGA) infants have increased risk of mortality and morbidity. Although both FGR and SGA infants have low birthweights for gestational age, a diagnosis of FGR also requires assessments of umbilical artery Doppler, physiological determinants, neonatal features of malnutrition, and in utero growth retardation. Both FGR and SGA are associated with adverse neurodevelopmental outcomes ranging from learning and behavioral difficulties to cerebral palsy. Up to 50% of FGR, newborns are not diagnosed until around the time of birth, yet this diagnosis lacks further indication of the risk of brain injury or adverse neurodevelopmental outcomes. Blood biomarkers may be a promising tool. Defining blood biomarkers indicating an infant's risk of brain injury would provide the opportunity for early detection and therefore earlier support. The aim of this review was to summarize the current literature to assist in guiding the future direction for the early detection of adverse brain outcomes in FGR and SGA neonates. The studies investigated potential diagnostic blood biomarkers from cord and neonatal blood or serum from FGR and SGA human neonates. Results were often conflicting with heterogeneity common in the biomarkers examined, timepoints, gestational age, and definitions of FGR and SGA used. Due to these variations, it was difficult to draw strong conclusions from the results. The search for blood biomarkers of brain injury in FGR and SGA neonates should continue as early detection and intervention is critical to improve outcomes for these neonates.

Sexual Dimorphism in the Closure of the Hippocampal Postnatal Critical Period of Synaptic Plasticity after Intrauterine Growth Restriction: Link to Oligodendrocyte and Glial Dysregulation

Intrauterine growth restriction (IUGR) resulting from hypertensive disease of pregnancy (HDP) leads to sexually dimorphic hippocampal-dependent cognitive and memory impairment in humans. In our translationally relevant mouse model of IUGR incited by HDP, we have previously shown that the synaptic development in the dorsal hippocampus including GABAergic development, NPTX2+ excitatory synaptic formation, axonal myelination, and perineural net (PNN) formation were perturbed by IUGR at adolescent equivalence in humans (P40). The persistence of these disturbances through early adulthood and the potential upstream mechanisms are currently unknown. Thus, we hypothesized that NPTX2+ expression, PNN formation, axonal myelination, all events closing synaptic development in the hippocampus, will be persistently perturbed, particularly affecting IUGR female mice through P60 given the fact that they had worse short-term recognition memory in this model. We additionally hypothesized that such sexual dimorphism is linked to persistent glial dysregulation. We induced IUGR by a micro-osmotic pump infusion of a potent vasoconstrictor U-46619, a thromboxane A2-analog, in the last week of the C57BL/6 mouse gestation to precipitate HDP. Sham-operated mice were used as controls. At P60, we assessed hippocampal and hemispheric volumes, NPTX2 expression, PNN formation, as well as myelin basic protein (MBP), Olig2, APC/CC1, and M-NF expression. We also evaluated P60 astrocytic (GFAP) reactivity and microglial (Iba1 and TMEM119) activation using immunofluorescent-immunohistochemistry and Imaris morphological analysis plus cytokine profiling using Meso Scale Discovery platform. IUGR offspring continued to have smaller hippocampal volumes at P60 not related to changes in hemisphere volume. NPTX2+ puncta counts and volumes were decreased in IUGR hippocampal CA subregions of female mice compared to sex-matched shams. Intriguingly, NPTX2+ counts and volumes were concurrently increased in the dentate gyrus (DG) subregion. PNN volumes were smaller in CA1 and CA3 of IUGR female mice along with PNN intensity in CA3 but they had larger volumes in the CA3 of IUGR male mice. The myelinated axon (MBP+) areas, volumes, and lengths were all decreased in the CA1 of IUGR female mice compared to sex-matched shams, which correlated with a decrease in Olig2 nuclear expression. No decrease in the number of APC/CC1+ mature oligodendrocytes was identified. We noted an increase in M-NF expression in the mossy fibers connecting DG to CA3 only in IUGR female mice. Reactive astrocytes denoted by GFAP areas, volumes, lengths, and numbers of branching were increased in IUGR female CA1 but not in IUGR male CA3 compared to sex-matched shams. Lastly, activated microglia were only detected in IUGR female CA1 and CA3 subregions. We detected no difference in the cytokine profile between sham and IUGR adult mice of either sex. Collectively, our data support a sexually dimorphic impaired closure of postnatal critical period of synaptic plasticity in the hippocampus of young adult IUGR mice with greater effects on females. A potential mechanism supporting such dimorphism may include oligodendrocyte dysfunction in IUGR females limiting myelination, allowing axonal overgrowth followed by a reactive glial-mediated synaptic pruning.

Speech-Encoding Deficits in Neonates Born Large-for-Gestational Age as Revealed With the Envelope Frequency-Following Response

OBJECTIVES

The present envelope frequency-following response (FFRENV) study aimed at characterizing the neural encoding of the fundamental frequency of speech sounds in neonates born at the higher end of the birth weight continuum (>90th percentile), known as large-for-gestational age (LGA).

DESIGN

Twenty-five LGA newborns were recruited from the maternity unit of Sant Joan de Déu Barcelona Children's Hospital and paired by age and sex with 25 babies born adequate-for-gestational age (AGA), all from healthy mothers and normal pregnancies. FFRENVs were elicited to the/da/ syllable and recorded while the baby was sleeping in its cradle after a successful universal hearing screening. Neural encoding of the stimulus' envelope of the fundamental frequency (F0ENV) was characterized through the FFRENV spectral amplitude. Relationships between electrophysiological parameters and maternal/neonatal variables that may condition neonatal neurodevelopment were assessed, including pregestational body mass index (BMI), maternal gestational weight gain and neonatal BMI.

RESULTS

LGA newborns showed smaller spectral amplitudes at the F0ENV compared to the AGA group. Significant negative correlations were found between neonatal BMI and the spectral amplitude at the F0ENV.

CONCLUSIONS

Our results indicate that in spite of having a healthy pregnancy, LGA neonates' central auditory system is impaired in encoding a fundamental aspect of the speech sounds, namely their fundamental frequency. The negative correlation between the neonates' BMI and FFRENV indicates that this impaired encoding is independent of the pregnant woman BMI and weight gain during pregnancy, supporting the role of the neonatal BMI. We suggest that the higher adipose tissue observed in the LGA group may impair, via proinflammatory products, the fine-grained central auditory system microstructure required for the neural encoding of the fundamental frequency of speech sounds.

Does the Blood-Brain Barrier Integrity Change in Regard to the Onset of Fetal Growth Restriction?

The aim of the study was to determine whether early-onset and late-onset fetal growth restriction (FGR) differentially affects the blood-brain barrier integrity. Furthermore, the purpose of the study was to investigate the relationship between the blood-brain barrier breakdown and neurological disorders in FGR newborns. To evaluate the serum tight junction (TJ) proteins and the placental TJ proteins expression, an ELISA method was used. A significant difference in serum OCLN concentrations was noticed in pregnancies complicated by the early-onset FGR, in relation to the intraventricular hemorrhage (IVH) occurrence in newborns. No significant differences in concentrations of the NR1 subunit of the N-methyl-d-aspartate receptor (NR1), nucleoside diphosphate kinase A (NME1), S100 calcium-binding protein B (S100B), occludin (OCLN), claudin-5 (CLN5), zonula occludens-1 (zo-1), the CLN5/zo-1 ratio, and the placental expression of OCLN, CLN5, claudin-4 (CLN4), zo-1 were noticed between groups. The early-onset FGR was associated with a higher release of NME1 into the maternal circulation in relation to the brain-sparing effect and premature delivery. Additionally, in late-onset FGR, the higher release of the S100B into the maternal serum in regard to fetal distress was observed. Furthermore, there was a higher release of zo-1 into the maternal circulation in relation to newborns' moderate acidosis in late-onset FGR. Blood-brain barrier disintegration is not dependent on pregnancy advancement at the time of FGR diagnosis. NME1 may serve as a biomarker useful in the prediction of fetal circulatory centralization and extremely low birth weight in pregnancies complicated by the early-onset FGR. Moreover, the serum zo-1 concentration may have prognostic value for moderate neonatal acidosis in late-onset FGR pregnancies.

Blood-Brain Barrier Disintegration in Growth-Restricted Fetuses with Brain Sparing Effect

The endothelial cells of the blood-brain barrier adhere closely, which is provided by tight junctions (TJs). The aim of the study was to assess the damage to the endothelial TJs in pregnancy, complicated by fetal growth restriction (FGR) and circulatory centralization (brain-sparing effect, BS). The serum concentrations of NR1 subunit of the N-methyl-D-aspartate receptor (NR1), nucleoside diphosphate kinase A (NME1), S100 calcium-binding protein B (S100B), occludin (OCLN), claudin-5 (CLN5), and zonula occludens protein – 1 (zo-1), and the placental expressions of OCLN, claudin-4 (CLN4), CLN5, and zo-1 were assessed with ELISA. The significantly higher serum NME1 concentrations and the serum CLN5/zo-1 index were observed in FGR pregnancy with BS, as compared to the FGR group without BS. The FGR newborns with BS were about 20 times more likely to develop an intraventricular hemorrhage (IVH) than the FGR infants without BS. The cerebroplacental ratio (CPR) allowed to predict the IVH in growth-restricted fetuses. The significantly lower placental CLN4 expression was observed in the FGR group with BS and who postnatally developed an IVH, as compared to the growth-restricted infants with BS without IVH signs. Pregnancy complicated by FGR and BS is associated with the destabilization of the fetal blood-brain barrier. The IVH in newborns is reflected in the inhibition of the placental CLN4 expression, which may be a useful marker in the prediction of an IVH among growth-restricted fetuses.

Maternal Serum and Umbilical Cord Brain Natriuretic Peptide Levels in Fetuses with Intrauterine Growth Restriction

Aim: We compared maternal serum and fetal cord blood proBNP levels in healthy pregnancies to those with intrauterine growth restriction (IUGR). Methods: Prospectively, maternal and cord blood samples at childbirth of 40 pregnant women with isolated IUGR and 40 healthy pregnant women were evaluated for ProBNP levels. Results: The mean serum ProBNP level was significantly higher in newborn cord blood with IUGR than in the control group (181.28 ± 145.37 vs. 91.41 ± 49.77 pg/mL, p = <0.01). Mean serum ProBNP level trended higher in women with IUGR compared to the controls, but was not statistically significant (124.21 ± 113.32 vs. 88.73 ± 85.18 pg/mL, p= >0.05). Conclusion: Third trimester mean proBNP in fetal cord blood are increased in IUGR fetuses at term birth compared to pregnancies with normal fetal growth.

Changes in structural brain development after selective fetal growth restriction in monochorionic twins

OBJECTIVES

Fetal growth restriction (FGR) may alter brain development permanently, resulting in lifelong structural and functional changes. However, in studies addressing this research question, FGR singletons have been compared primarily to matched appropriately grown singletons, a design which is inherently biased by differences in genetic and maternal factors. To overcome these limitations, we conducted a within-pair comparison of neonatal structural cerebral ultrasound measurements in monochorionic twin pairs with selective FGR (sFGR).

METHODS

Structural cerebral measurements on neonatal cerebral ultrasound were compared between the smaller and larger twins of monochorionic twin pairs with sFGR, defined as a birth-weight discordance (BWD) ≥ 20%, born in our center between 2010 and 2020. Measurements from each twin pair were also compared with those of an appropriately grown singleton, matched according to sex and gestational age at birth.

RESULTS

Included were 58 twin pairs with sFGR, with a median gestational age at birth of 31.7 (interquartile range, 29.9-33.8) weeks and a median birth weight of 1155 g for the smaller twin and 1725 g for the larger twin (median BWD, 32%). Compared with both the larger twin and the singleton, the smaller twin had significantly smaller cerebral structures (corpus callosum, vermis, cerebellum), less white/deep gray matter and smaller intracranial surface area and volume. Intracranial-volume discordance and BWD correlated significantly (R²  = 0.228, P < 0.0001). The median intracranial-volume discordance was smaller than the median BWD (19% vs 32%, P < 0.0001). After correction for intracranial volume, only one of the observed differences (biparietal diameter) remained significant for the smaller twin vs both the larger twin and the singleton.

CONCLUSIONS

In monochorionic twins with sFGR, neonatal cerebral ultrasound reveals an overall, proportional restriction in brain growth, with smaller cerebral structures, less white/deep gray matter and smaller overall brain-size parameters in the smaller twin. There was a positive linear relationship between BWD and intracranial-volume discordance, with intracranial-volume discordance being smaller than BWD. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.

Fetal neurosonography at 31-35 weeks reveals altered cortical development in pre-eclampsia with and without small-for-gestational-age fetus

OBJECTIVE

To explore the pattern of fetal cortical development in pregnancies complicated by pre-eclampsia (PE), with and without a small-for-gestational-age (SGA) fetus, compared to uncomplicated pregnancies.

METHODS

This was a prospective observational study including singleton pregnancies complicated by normotensive SGA (birth weight < 10^th centile) (n = 77), PE with an appropriate-for-gestational-age (AGA) fetus (n = 76) or PE with a SGA fetus (n = 67), and 128 uncomplicated pregnancies (normotensive AGA) matched by gestational age at ultrasound. All pregnancies underwent detailed neurosonography, using a transabdominal and transvaginal approach, at 31-35 weeks' gestation to assess the depth of the insula, Sylvian fissure, parieto-occipital sulcus, cingulate sulcus and calcarine sulcus. All measurements were adjusted for biparietal diameter (BPD). In addition, a grading score of cortical development was assigned to each brain structure, ranging from Grade 0 (no development) to Grade 5 (maximum development). Univariate and multiple regression analyses were conducted.

RESULTS

Similar to findings in previous studies, normotensive pregnancies with a SGA fetus showed significant differences in cortical development compared with controls, with reduced Sylvian fissure depth adjusted for BPD (14.5 ± 2.4 vs 16.6 ± 2.3; P < 0.001) and increased insula depth adjusted for BPD (33.2 ± 2.0 vs 31.8 ± 2.0; P < 0.001). Interestingly, a similar cortical development pattern was observed in PE pregnancies with a SGA fetus and in PE pregnancies with an AGA fetus, manifested by reduced Sylvian fissure depth adjusted for BPD (14.2 ± 2.3 and 14.3 ± 2.3 vs 16.6 ± 2.3; P < 0.001 for both) and greater insula depth adjusted for BPD (33.2 ± 2.1 and 32.8 ± 1.7 vs 31.8 ± 2.0; P < 0.001 for both) compared with controls. No significant differences were observed in parieto-occipital, cingulate sulcus or calcarine sulcus depth across the study groups. The Sylvian fissure was scored as Grade 4 in significantly more (93.2% vs 59.5%) and as Grade 5 in significantly fewer (2.7% vs 37.3%) PE pregnancies with an AGA fetus compared with controls (P < 0.05 for both). These differences remained significant even after statistical adjustment for potential confounders, including ethnicity, low socioeconomic status, nulliparity, chronic hypertension, pregestational diabetes, assisted reproductive technologies, smoking and fetal gender, with the application of Benjamini-Hochberg procedure for multiple comparisons.

CONCLUSIONS

PE with or without SGA is associated with a differential fetal cortical development pattern which is similar to that described previously in small fetuses. Future research is warranted to elucidate better the mechanism(s) underlying these changes. © 2022 International Society of Ultrasound in Obstetrics and Gynecology.

Doppler Ultrasound of the Umbilical Artery: Clinical Application

OBJECTIVE

 To provide a survey of relevant literature on umbilical artery Doppler ultrasound use in clinical practice, technical considerations and limitations, and future perspectives.

METHODS

 Literature searches were conducted in PubMed and Medline, restricted to articles written in English. Additionally, the references of all analyzed studies were searched to obtain necessary information.

RESULTS

 The use of this technique as a routine surveillance method is only recommended for high-risk pregnancies with impaired placentation. Meta-analyses of randomized trials have established that obstetric management guided by umbilical artery Doppler findings can improve perinatal mortality and morbidity. The values of the indices of Umbilical artery Doppler decrease with advancing gestational age; however, a lack of consensus on reference ranges prevails.

CONCLUSION

 Important clinical decisions are based on the information obtained with umbilical artery Doppler ultrasound. Future efforts in research are imperative to overcome the current limitations of the technique.

First-trimester biomarkers and the risk of cerebral palsy

BACKGROUND

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

AIMS

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

STUDY DESIGN

Nationwide cohort study.

SUBJECTS

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

OUTCOME MEASURES

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

RESULTS

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

CONCLUSIONS

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

Brain-Derived Neurotrophic Factor Levels in Cord Blood from Growth Restricted Fetuses with Doppler Alteration Compared to Adequate for Gestational Age Fetuses

Background and Objectives: Fetal growth restriction (FGR) is a severe obstetric disease characterized by a low fetal size entailing a set of undesired consequences. For instance, previous studies have noticed a worrisome association between FGR with an abnormal neurodevelopment. However, the precise link between FGR and neurodevelopmental alterations are not yet fully understood yet. Brain-derived neurotrophic factor (BDNF) is a critical neurotrophin strongly implicated in neurodevelopmental and other neurological processes. In addition, serum levels of BDNF appears to be an interesting indicator of pathological pregnancies, being correlated with the neonatal brain levels. Therefore, the aim of this study is to analyze the blood levels of BDNF in the cord blood from fetuses with FGR in comparison to those with weight appropriate for gestational age (AGA). Materials and Methods: In this study, 130 subjects were recruited: 91 in group A (AGA fetuses); 39 in group B (16 FGR fetuses with exclusively middle cerebral artery (MCA) pulsatility index (PI) < 5th percentile and 23 with umbilical artery (UA) PI > 95th percentile). Serum levels of BDNF were determined through ELISA reactions in these groups. Results: Our results show a significant decrease in cord blood levels of BDNF in FGR and more prominently in those with UA PI >95th percentile in comparison to AGA. FGR fetuses with exclusively decreased MCA PI below the 5th percentile also show reduced levels of BDNF than AGA, although this difference was not statistically significant. Conclusions: Overall, our study reports a potential pathophysiological link between reduced levels of BDNF and neurodevelopmental alterations in fetuses with FGR. However, further studies should be conducted in those FGR subjects with MCA PI < 5th percentile in order to understand the possible implications of BDNF in this group.

Electroencephalographic studies in growth-restricted and small-for-gestational-age neonates

Foetal growth restriction (FGR) and being born small for gestational age (SGA) are associated with neurodevelopmental delay. Early diagnosis of neurological damage is difficult in FGR and SGA neonates. Electroencephalography (EEG) has the potential as a tool for the assessment of brain development in FGR/SGA neonates. In this review, we analyse the evidence base on the use of EEG for the assessment of neonates with FGR or SGA. We found consistent findings that FGR/SGA is associated with measurable changes in the EEG that present immediately after birth and persist into childhood. Early manifestations of FGR/SGA in the EEG include changes in spectral power, symmetry/synchrony, sleep-wake cycling, and the continuity of EEG amplitude. Later manifestations of FGR/SGA into infancy and early childhood include changes in spectral power, sleep architecture, and EEG amplitude. FGR/SGA infants had poorer neurodevelopmental outcomes than appropriate for gestational age controls. The EEG has the potential to identify FGR/SGA infants and assess the functional correlates of neurological damage. IMPACT: FGR/SGA neonates have significantly different EEG activity compared to AGA neonates. EEG differences persist into childhood and are associated with adverse neurodevelopmental outcomes. EEG has the potential for early identification of brain impairment in FGR/SGA neonates.

Intrauterine Growth Restriction Disrupts the Postnatal Critical Period of Synaptic Plasticity in the Mouse Dorsal Hippocampus in a Model of Hypertensive Disease of Pregnancy

INTRODUCTION

Intrauterine growth restriction (IUGR) from hypertensive disease of pregnancy complicates up to 10% of all pregnancies. Significant hippocampal-dependent cognitive and memory impairments as well as neuropsychiatric disorders have been linked to IUGR. Because disturbance of the hippocampal critical period (CPd) of synaptic plasticity leads to impairments similar to those described in IUGR human offspring, we hypothesized that IUGR would perturb the CPd of synaptic plasticity in the mouse hippocampus in our model.

METHODS

IUGR was produced by a micro-osmotic pump infusion of the potent vasoconstrictor U-46619, a thromboxane A2-agonist, at embryonic day 12.5 in C57BL/6J mouse dams to precipitate hypertensive disease of pregnancy and IUGR. Sham-operated mice acted as controls. At P10, P18, and P40, we assessed astrogliosis using GFAP-IHC. In dorsal CA1 and CA3 subfields, we assessed the immunoreactivities (IR) (IF-IHC) to (i) parvalbumin (PV) and glutamate decarboxylase (GAD) 65/67, involved in CPd onset; (ii) PSA-NCAM that antagonizes CPd onset; (iii) NPTX2, necessary for excitatory synapse formation and engagement of CPd; and (iv) MBP and WFA, staining perineural nets (PNNs), marking CPd closure. ImageJ/Fiji and IMARIS were used for image processing and SPSS v24 for statistical analysis.

RESULTS

Although PV+ interneuron numbers and IR intensity were unchanged, development of GAD65/67+ synaptic boutons was accelerated at P18 IUGR mice and inversely correlated with decreased expression of PSA-NCAM in the CA of P18 IUGR mice at P18. NPTX2+ puncta and total volume were persistently decreased in the CA3 pyramidal and radiatum layers of IUGR mice from P18 to P40. At P40, axonal myelination (MBP+) in CA3 of IUGR mice was decreased and correlated with NPTX2 deficits. Lastly, the volume and integrity of the PNNs in the dorsal CA was disrupted in IUGR mice at P40.

DISCUSSION/CONCLUSION

IUGR disrupts the molecular and structural initiation, consolidation, and closure of the CPd of synaptic plasticity in the mouse hippocampus in our model, which may explain the learning and memory deficits observed in juvenile IUGR mice and the cognitive disorders seen in human IUGR offspring. The mechanistic links warrant further investigation, to identify therapeutic targets to prevent neurodevelopmental deficits in patients affected by IUGR.

Prenatal Environment and Neurodevelopmental Disorders

The internal and external environment of the mother during the developmental stages of the fetus affects the offspring's health. According to the developmental origins of health and disease (DOHaD) theory, environmental factors influence the offspring and also affect health in adulthood. Recently, studies based on this theory have gained attracted attention because of their clinical utility in identifying the risk groups for various diseases. Neurodevelopmental disorders (NDDs) such as autism spectrum disorder (ASD) and attention-deficit hyperactivity disorder (ADHD) can be caused by exposure to certain prenatal environments during pregnancy. This review describes the latest findings on the effect of prenatal environment on the onset mechanism of NDDs based on the DOHaD theory. Unravelling the molecular mechanisms underlying the pathogenesis of NDDs is important, because there are no therapeutic drugs for these disorders. Furthermore, elucidating the relationship between the DOHaD theory and NDDs will contribute to the popularization of preventive medicine.

Overexpression of microRNAs miR-25-3p, miR-185-5p and miR-132-3p in Late Onset Fetal Growth Restriction, Validation of Results and Study of the Biochemical Pathways Involved

In a prospective study, 48 fetuses were evaluated with Doppler ultrasound after 34 weeks and classified, according to the cerebroplacental ratio (CPR) and estimated fetal weight (EFW), into fetuses with normal growth and fetuses with late-onset fetal growth restriction (LO-FGR). Overexpression of miRNAs from neonatal cord blood belonging to LO-FGR fetuses, was validated by real-time PCR. In addition, functional characterization of overexpressed miRNAs was performed by analyzing overrepresented pathways, gene ontologies, and prioritization of synergistically working miRNAs. Three miRNAs: miR-25-3p, miR-185-5p and miR-132-3p, were significantly overexpressed in cord blood of LO-FGR fetuses. Pathway and gene ontology analysis revealed over-representation of certain molecular pathways associated with cardiac development and neuron death. In addition, prioritization of synergistically working miRNAs highlighted the importance of miR-185-5p and miR-25-3p in cholesterol efflux and starvation responses associated with LO-FGR phenotypes. Evaluation of miR-25-3p; miR-132-3p and miR-185-5p might serve as molecular biomarkers for the diagnosis and management of LO-FGR; improving the understanding of its influence on adult disease.

Prenatal administration of IL-1Ra attenuate the neurodevelopmental impacts following non-pathogenic inflammation during pregnancy

Prenatal inflammation negatively affects placental function, subsequently altering fetal development. Pathogen-associated molecular patterns (PAMPs) are used to mimics infections in preclinical models but rarely detected during pregnancy. Our group previously developed an animal model of prenatal exposure to uric acid (endogenous mediator), leading to growth restriction alongside IL-1-driven placental inflammation (Brien et al. in J Immunol 198(1):443–451, 2017). Unlike PAMPs, the postnatal impact of prenatal non-pathogenic inflammation is still poorly understood. Therefore, we investigated the effects of prenatal uric acid exposure on postnatal neurodevelopment and the therapeutic potential of the IL-1 receptor antagonist; IL-1Ra. Uric acid induced growth restriction and placental inflammation, which IL-1Ra protected against. Postnatal evaluation of both structural and functional aspects of the brain revealed developmental changes. Both astrogliosis and microgliosis were observed in the hippocampus and white matter at postnatal day (PND)7 with IL-1Ra being protective. Decreased myelin density was observed at PND21, and reduced amount of neuronal precursor cells was observed in the Dentate Gyrus at PND35. Functionally, motor impairments were observed as evaluated with the increased time to fully turn upward (180 degrees) on the inclined plane and the pups were weaker on the grip strength test. Prenatal exposure to sterile inflammation, mimicking most clinical situation, induced growth restriction with negative impact on neurodevelopment. Targeted anti-inflammatory intervention prenatally could offer a strategy to protect brain development during pregnancy.

Change of pace: How developmental tempo varies to accommodate failed provision of early needs

The interplay of genes and environments (GxE) is a fundamental source of variation in behavioral and developmental outcomes. Although the role of developmental time (T) in the unfolding of such interactions has yet to be fully considered, GxE operates within a temporal frame of reference across multiple timescales and degrees of biological complexity. Here, we consider GxExT interactions to understand adversity-induced developmental acceleration or deceleration whereby environmental conditions hasten or hinder children's development. To date, developmental pace changes have been largely explained through a focus on the individual: for example, how adversity "wears down" aging biological systems or how adversity accelerates or decelerates maturation to optimize reproductive fitness. We broaden such theories by positing shifts in developmental pace in response to the parent-child dyad's capacity or incapacity for meeting children's early, physiological and safety needs. We describe empirical evidence and potential neurobiological mechanisms supporting this new conceptualization of developmental acceleration and deceleration. We conclude with suggestions for future research on the developmental consequences of early adverse exposures.

An integrated approach based on advanced CTG parameters and Doppler measurements for late growth restriction management

Background

The clinical diagnosis of late Fetal Growth Restriction (FGR) involves the integration of Doppler ultrasound data and Fetal Heart Rate (FHR) monitoring through computer assisted computerized cardiotocography (cCTG). The aim of the study was to evaluate the diagnostic power of combined Doppler and cCTG parameters by contrasting late FGR –and healthy controls.

Methods

The study was conducted from January 2018 to May 2020. Only pregnant women who had the last Doppler measurement obtained within 1 week before delivery and cCTG performed within 24 h before delivery were included in the study. Two hundred forty-nine pregnant women fulfilling the inclusion criteria were enrolled in the study; 95 were confirmed as late FGR and 154 were included in the control group.

Results

Among the extracted cCTG parameters, Delta Index, Short Term Variability (STV), Long Term Variability (LTV), Acceleration and Deceleration Phase Rectified Slope (APRS, DPRS) values were lower in the late FGR participants compared to the control group. In the FGR cohort, Delta, STV, APRS, and DPRS were found different when stratifying by MCA_PI (MCA_PI <5th centile or > 5th centile). STV and DPRS were the only parameters to be found different when stratifying by (UA_PI >95th centile or UA_PI <95th centile). Additionally, we measured the predictive power of cCTG parameters toward the identification of associated Doppler measures using figures of merit extracted from ROC curves.

The AUC of ROC curves were accurate for STV (0,70), Delta (0,68), APRS (0,65) and DPRS (0,71) when UA_PI values were > 95th centile while, the accuracy attributable to the prediction of MCA_PI was 0.76, 0.77, 0.73, and 0.76 for STV, Delta, APRS, and DPRS, respectively.

An association of UA_PI>95th centile and MCA_PI<5th centile with higher risk for NICU admission, was observed, while CPR < 5th centile resulted not associated with any perinatal outcome. Values of STV, Delta, APRS, DPRS were significantly lower for FGR neonates admitted to NICU, compared with the uncomplicated FGR cohort.

Conclusions

The results of this study show the contribution of advanced cCTG parameters and fetal Doppler to the identification of late FGR and the association of those parameters with the risk for NICU admission.

Trial registration

Retrospectively registered.

Deficient neural encoding of speech sounds in term neonates born after fetal growth restriction

Infants born after fetal growth restriction (FGR)-an obstetric condition defined as the failure to achieve the genetic growth potential-are prone to neurodevelopmental delays, with language being one of the major affected areas. Yet, while verbal comprehension and expressive language impairments have been observed in FGR infants, children and even adults, specific related impairments at birth, such as in the ability to encode the sounds of speech, necessary for language acquisition, remain to be disclosed. Here, we used the frequency-following response (FFR), a brain potential correlate of the neural phase locking to complex auditory stimuli, to explore the encoding of speech sounds in FGR neonates. Fifty-three neonates born with FGR and 48 controls born with weight adequate-for-gestational age (AGA) were recruited. The FFR was recorded to the consonant-vowel stimulus (/da/) during sleep and quantified as the spectral amplitude to the fundamental frequency of the syllable and its signal-to-noise ratio (SNR). The outcome was available in 45 AGA and 51 FGR neonates, yielding no differences for spectral amplitudes. However, SNR was strongly attenuated in the FGR group compared to the AGA group at the vowel region of the stimulus. These findings suggest that FGR population present a deficit in the neural pitch tracking of speech sounds already present at birth. Our results pave the way for future research on the potential clinical use of the FFR in this population, so that if confirmed, a disrupted FFR recorded at birth may help deriving FGR neonates at risk for postnatal follow-ups.

Neurodevelopmental Outcomes following Intrauterine Growth Restriction and Very Preterm Birth

OBJECTIVES

To evaluate whether intrauterine growth restriction (IUGR) adds further neurodevelopmental risk to that posed by very preterm birth alone in terms of alterations in brain growth and poorer toddlerhood outcomes.

STUDY DESIGN

Participants were 314 infants of very preterm birth enrolled in the Evaluation of Preterm Imaging Study (e-Prime) who were subsequently followed up in toddlerhood. IUGR was identified postnatally from discharge records (n = 49) and defined according to prenatal evaluation of growth restriction confirmed by birth weight <10th percentile for gestational age and/or alterations in fetal Doppler. Appropriate for gestational age (AGA; n = 265) was defined as birth weight >10th percentile for gestational age at delivery. Infants underwent magnetic resonance imaging at term-equivalent age (median = 42 weeks); T2-weighted images were obtained for voxelwise gray matter volumes. Follow-up assessments were conducted at corrected median age of 22 months using the Bayley Scales of Infant and Toddler Development III and the Modified-Checklist for Autism in Toddlers.

RESULTS

Infants of very preterm birth with IUGR displayed a relative volumetric decrease in gray matter in limbic regions and a relative increase in frontoinsular, temporal-parietal, and frontal areas compared with peers of very preterm birth who were AGA. At follow-up, toddlers born very preterm with IUGR had significantly lower cognitive (effect size = 0.42) and motor (effect size = 0.41) scores and were more likely to have a positive Modified-Checklist for Autism in Toddlers screening for autism (OR = 2.12) compared with peers of very preterm birth who were AGA.

CONCLUSIONS

IUGR might confer a neurodevelopmental risk that is greater than that posed by very preterm alone, in terms of both alterations in brain growth and poorer toddlerhood outcomes.

Examination of fetal well-being evaluation metrics for fetal growth restriction as seen from Japan Obstetric Compensation Cause Analysis Report data

Advances in perinatal care have improved the prognoses of both mothers and neonates; however, cerebral palsy continues to occur. In this study, we examined methods for the intragestational evaluation of the health of infants who later developed cerebral palsy. A retrospective review was conducted on light-for-dates cases among the 2113 cause analysis reports issued by the Japan Obstetric Compensation System between January 2009 and September 2018. In our examination, we determined that non-stress tests and ultrasonic Doppler tests were used to evaluate fetal well-being. Moreover, we observed cases in which additional testing was not performed even when fetal growth restriction (FGR) was identified. Appropriate management of FGR may help reduce the incidence of cerebral palsy.

Altered trajectory of neurodevelopment associated with fetal growth restriction

Fetal growth restriction (FGR) is principally caused by suboptimal placental function. Poor placental function causes an under supply of nutrients and oxygen to the developing fetus, restricting development of individual organs and overall growth. Estimated fetal weight below the 10th or 3rd percentile with uteroplacental dysfunction, and knowledge regarding the onset of growth restriction (early or late), provide diagnostic criteria for fetuses at greatest risk for adverse outcome. Brain development and function is altered with FGR, with ongoing clinical and preclinical studies elucidating neuropathological etiology. During the third trimester of pregnancy, from ~28 weeks gestation, neurogenesis is complete and neuronal complexity is expanding, through axonal and dendritic outgrowth, dendritic branching and synaptogenesis, accompanied by myelin production. Fetal compromise over this period, as occurs in FGR, has detrimental effects on these processes. Total brain volume and grey matter volume is reduced in infants with FGR, first evident in utero, with cortical volume particularly vulnerable. Imaging studies show that cerebral morphology is disturbed in FGR, with altered cerebral cortex, volume and organization of brain networks, and reduced connectivity of long- and short-range circuits. Thus, FGR induces a deviation in brain development trajectory affecting both grey and white matter, however grey matter volume is preferentially reduced, contributed by cell loss, and reduced neurite outgrowth of surviving neurons. In turn, cell-to-cell local networks are adversely affected in FGR, and whole brain left and right intrahemispheric connections and interhemispheric connections are altered. Importantly, disruptions to region-specific brain networks are linked to cognitive and behavioral impairments.

Gestational Hypoxia and Blood-Brain Barrier Permeability: Early Origins of Cerebrovascular Dysfunction Induced by Epigenetic Mechanisms

Fetal chronic hypoxia leads to intrauterine growth restriction (IUGR), which is likely to reduce oxygen delivery to the brain and induce long-term neurological impairments. These indicate a modulatory role for oxygen in cerebrovascular development. During intrauterine hypoxia, the fetal circulation suffers marked adaptations in the fetal cardiac output to maintain oxygen and nutrient delivery to vital organs, known as the "brain-sparing phenotype." This is a well-characterized response; however, little is known about the postnatal course and outcomes of this fetal cerebrovascular adaptation. In addition, several neurodevelopmental disorders have their origins during gestation. Still, few studies have focused on how intrauterine fetal hypoxia modulates the normal brain development of the blood-brain barrier (BBB) in the IUGR neonate. The BBB is a cellular structure formed by the neurovascular unit (NVU) and is organized by a monolayer of endothelial and mural cells. The BBB regulates the entry of plasma cells and molecules from the systemic circulation to the brain. A highly selective permeability system achieves this through integral membrane proteins in brain endothelial cells. BBB breakdown and dysfunction in cerebrovascular diseases lead to leakage of blood components into the brain parenchyma, contributing to neurological deficits. The fetal brain circulation is particularly susceptible in IUGR and is proposed to be one of the main pathological processes deriving BBB disruption. In the last decade, several epigenetic mechanisms activated by IU hypoxia have been proposed to regulate the postnatal BBB permeability. However, few mechanistic studies about this topic are available, and little evidence shows controversy. Therefore, in this mini-review, we analyze the BBB permeability-associated epigenetic mechanisms in the brain exposed to chronic intrauterine hypoxia.

Fetal neurosonography detects differences in cortical development and corpus callosum in late-onset small fetuses

OBJECTIVE

To explore whether neurosonography can detect differences in cortical development and corpus callosal length in late-onset small fetuses subclassified into small-for-gestational age (SGA) or growth restricted (FGR).

METHODS

This was a prospective cohort study in singleton pregnancies, including normally grown fetuses (birth weight between the 10^th and 90^th centiles) and late-onset small fetuses (estimated fetal weight < 10^th centile, diagnosed after 32 weeks of gestation and confirmed by birth weight < 10^th centile). Small fetuses were subclassified into SGA (birth weight between the 3^rd and 9^th centiles and normal fetoplacental Doppler) and FGR (birth weight < 3^rd centile and/or abnormal cerebroplacental ratio and/or abnormal uterine artery Doppler). Neurosonography was performed at 33 ± 1 weeks of gestation to assess the depth of the insula, Sylvian fissure and parieto-occipital sulcus in the axial views and corpus callosal length in the midsagittal plane. Measurements were performed offline using Alma Workstation software and were adjusted by biparietal diameter or cephalic index. Linear regression analysis was used to assess the association between the neurosonographic variables and study group, adjusting for confounding factors such as gender, gestational age at neurosonography, nulliparity and pre-eclampsia.

RESULTS

In total, 318 fetuses were included, of which 97 were normally grown and 221 were late-onset small fetuses that were further subdivided into late-onset SGA (n = 67) or late-onset FGR (n = 154). Compared to controls, both SGA and FGR cases showed significantly increased insular depth adjusted for biparietal diameter (median (interquartile range), controls 0.329 (0.312-0.342) vs SGA 0.339 (0.321-0.347) vs FGR 0.336 (0.325-0.349); P = 0.006). A linear tendency to reduced Sylvian fissure depth adjusted for biparietal diameter was also observed across the study groups (mean ± SD, controls 0.148 ± 0.021 vs SGA 0.142 ± 0.025 vs FGR 0.139 ± 0.022; P = 0.003). However, differences were significant only between the FGR and control groups. Corpus callosal length adjusted for cephalic index was significantly reduced in FGR cases compared with both controls and SGA cases, while there was no difference between SGA cases and controls (median (interquartile range), controls 0.500 (0.478-0.531) vs SGA 0.502 (0.487-0.526) vs FGR 0.475 (0.447-0.508); P = 0.005). No differences were found in parieto-occipital sulcus depth between the three study groups.

CONCLUSION

Neurosonography seems to be a sensitive tool to detect subtle structural differences in brain development in late-onset small fetuses. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.

Influence of Cerebral Vasodilation on Blood Reelin Levels in Growth Restricted Fetuses

Fetal growth restriction (FGR) is one of the most important obstetric pathologies. It is frequently caused by placental insufficiency. Previous studies have shown a relationship between FGR and impaired new-born neurodevelopment, although the molecular mechanisms involved in this association have not yet been completely clarified. Reelin is an extracellular matrix glycoprotein involved in development of neocortex, hippocampus, cerebellum and spinal cord. Reelin has been demonstrated to play a key role in regulating perinatal neurodevelopment and to contribute to the emergence and development of various psychiatric pathologies, and its levels are highly influenced by pathological conditions of hypoxia. The purpose of this article is to study whether reelin levels in new-borns vary as a function of severity of fetal growth restriction by gestational age and sex. We sub-grouped fetuses in: normal weight group (Group 1, n = 17), FGR group with normal umbilical artery Doppler and cerebral redistribution at middle cerebral artery Doppler (Group 2, n = 9), and FGR with abnormal umbilical artery Doppler (Group 3, n = 8). Our results show a significant association of elevated Reelin levels in FGR fetuses with cerebral blood redistribution compared to the normal weight group and the FGR with abnormal umbilical artery group. Future research should focus on further expanding the knowledge of the relationship of reelin and its regulated products with neurodevelopment impairment in new-borns with FGR and should include larger and more homogeneous samples and the combined use of different in vivo techniques in neonates with impaired growth during their different adaptive phases.

Taurine improves the differentiation of neural stem cells in fetal rats with intrauterine growth restriction via activation of the PKA-CREB-BDNF signaling pathway

Intrauterine growth restriction (IUGR) affects brain neural stem cell (NSC) differentiation. In the present study, we investigated whether taurine supplementation may improve NSC differentiation in IUGR fetal rats via the protein kinase A-cyclic adenosine monophosphate (cAMP) response element protein-brain derived neurotrophic factor (PKA-CREB-BDNF) signaling pathway. The IUGR fetal rat model was established with a low-protein diet. Fresh subventricular zone (SVZ) tissue from the fetuses on the 14th day of pregnancy was microdissected and dissociated into single-cell suspensions, then was cultured to form neurospheres. The neurospheres were divided into the control group, the IUGR group, the IUGR+taurine (taurine) group, the IUGR+H89 (H89) group and the IUGR+taurine+H89 (taurine+H89) group. The mRNA and protein expression levels of PKA, CREB and BDNF were measured by reverse transcription-polymerase chain reaction (RT-PCR) and Western blotting (WB). Tuj-1-positive neurons and GFAP-positive glial cells were detected by immunofluorescence. The total number of proliferating NSCs and the percentage of Tuj-1-positive neurons in the IUGR group were lower than those in the control group, but the percentage of GFAP-positive cells was higher in the IUGR group than in the control group. Taurine supplementation increased the total number of neural cells and the percentage of Tuj-1-positive neurons, and reduced the percentage of GFAP-positive cells among differentiated NSCs after IUGR. H89 reduced the total number and percentage of Tuj-1-positive neurons and increased the percentage of GFAP-positive cells. The mRNA and protein levels of PKA, CREB, and BDNF were lower in the IUGR group. The mRNA and protein expression levels of these factors were increased by taurine supplementation but reduced by the addition of H89. Taurine supplementation increased the ratio of neurons to glial cells and prevented gliosis in the differentiation of NSCs in IUGR fetal rats by activating the PKA-CREB-BDNF signaling pathway.

Fetal epicardial fat thickness in fetal growth restriction; effects on fetal heart function and relationship with the severity of disease

OBJECTIVE

To investigate fetal epicardial fat thickness (EFT) value in fetal growth restriction (FGR) and its relationship with clinical parameters, fetal modified myocardial index (Mod-MPI), and the Doppler parameters.

MATERIAL METHODS

Eighty-five pregnant women, with 30 diagnosed with FGR and 55 healthy pregnant women as control group participated in this prospective case-control study. FGR group was divided into 2 subgroups as early (n = 9) and late FGR (n = 21) groups. Demographic data were taken from the medical records. Amnion fluid value, fetal biometric measurements, and Doppler parameters were obtained. Fetal EFT and fetal Mod-MPI were measured by using the echocardiographic methods. The correlation tests were performed to assess the association between EFT and clinical and ultrasonographic parameters. p < .05 was interpreted as statistically significant.

RESULTS

EFT value was found statistically lower in the early and late FGR groups than the control group (p = .003). Higher umbilical artery pulsatility index (PI) and lower cerebroplacental ratio (CPR) values were found in the early and late FGR (p < .001, p = .001). The optimal EFT cutoff level to predict FGR disease was measured as 1.25 with 63.3% specificity and 77.4% sensitivity. Lower ejection time (ET) and higher Mod-MPI and isovolumetric contraction time (ICT) values were found in the group FGR with absent UAEDF than in the group FGR with no absent UAEDF (p = .001, p < .000, p < .000, respectively). Correlation tests showed statistically negative and weak correlations among EFT, umbilical artery PI, and mean Ut A-PI (p = .019, p = .019). Positive correlations were found in regard to gestational age, EFW, and EFT (p = .002, p < .000).

CONCLUSION

Our study showed that the measurement of EFT may contribute to predicting the diagnosis of FGR. Moreover, lower EFT values can be related to the severity of FGR. Future randomized control studies are needed to understand the effects and pathways of fetal EFT on fetal cardiac function.

Neurodevelopmental assessment of infants born to mothers with hypertensive disorder of pregnancy at six months of age

Infant neurodevelopment is a complex process which may be affected by different events during pregnancy, such as hypertensive disorders of pregnancy (HDP). We conducted a prospective cohort study to compare the prevalence of neurodevelopmental disorders in infants born to mothers with and without HDP at six months of age. Participants attended the Health Observatory of Instituto de Desarrollo e Investigaciones Pediátricas "Prof. Dr. Fernando E. Viteri" during 2018 and 2019. Infant neurodevelopment was assessed with the Bayley Scales of Infant and Toddler Development-Third Edition (Bayley-III). Data were analyzed using Chi-square, Student's t-test and Mann-Whitney test. Of the 132 participating infants, 68 and 64 were born to mothers with and without HDP, respectively. At six months, the prevalence of risk of neurodevelopmental delay was significantly higher in infants born to mothers with than without HDP (27.9% vs. 9.4%; p = 0.008) (odds ratio, 3.71; 95% confidence interval, 1.30; 12.28). In conclusion, infants born to mothers with HDP had three times increased risk of neurodevelopmental delay at six months of age.

Neurodevelopment of infant with late fetal growth restriction

Late fetal growth restriction has increasingly gain interest. Differently from early fetal growth restriction, the severity of this condition and the impact on perinatal mortality and morbidity is less severe. Nevertheless, there is some evidence to suggest that fetuses exposed to growth restriction late in pregnancy are at increased risk of neurological dysfunction and behavioral impairment. The aim of our review was to discuss the available evidence on the neurodevelopmental outcome in fetuses exposed to growth restriction late in pregnancy. Cerebral blood flow redistribution, a Doppler hallmark of late fetal growth restriction, has been associated with this increased risk, although there are still some controversies. Currently, most of the available studies are heterogeneous and do not distinguish between early and late fetal growth restriction when evaluating the long-term outcome, thus, making the correlation between late fetal growth restriction and neurological dysfunction difficult to interpret. The available evidence suggests that fetuses exposed to late growth restriction are at increased risk of neurological dysfunction and behavioral impairment. The presence of the cerebral blood flow redistribution seems to be associated with adverse neurodevelopmental outcome, however, from the present literature the causality cannot be ascertained.

A pilot study on investigating the role of Salvia miltiorrhiza in fetal growth restriction

To date there is no effective treatment for pregnancies complicated by fetal growth restriction (FGR). Salvia miltiorrhiza, a traditional Chinese herb has been shown to promote blood flow and improve microcirculatory disturbance. In this pilot study, we evaluated whether S. miltiorrhiza can potentially become a possible therapy for FGR. Nineteen pregnant women with FGR were treated with S. miltiorrhiza and ATP supplementation for an average of 7 days, and 17 cases received ATP supplementation as controls. The estimated fetal weights (EFWs) were measured by ultrasound after treatment, and the birthweights were recorded after birth. After treatment with S. miltiorrhiza, 7 (37%) FGR cases showed an increase in EFW to above the 10th percentile, compared with 4 (23%) FGR cases in controls (odds ratio: 1.896, 95% confidence limits (CLs): 0.44-8.144). At delivery, 10 (53%) FGR cases in the treatment group delivered babies with a birthweight above the 10th percentile, compared with 6 (35%) FGR cases in the control group (odds ratio: 2.037, 95% CL: 0.532-7.793); 80 or 64% FGR cases in the treatment group showed an increase in fetal abdominal circumference (AC) or biparietal diameter (BPD) above the 10th percentile before delivery. While 44 or 30% FGR cases in the control group showed an increase in AC or BPD. No improvement of head circumference (HC) or femur length (FL) was seen. These pilot data suggest the need for multicenter randomized clinical trials on the potential of S. miltiorrhiza to improve perinatal outcome in pregnant women complicated by FGR.

Twin discordance: a study of volumetric fetal brain MRI and neurodevelopmental outcome

OBJECTIVE

This study employed magnetic resonance imaging (MRI) to compare brain volumes of discordant twins and examined their neurodevelopment after birth by using a validated exam.

STUDY DESIGN

A prospective historical cohort study of discordant dichorionic diamniotic (DCDA) or monochorionic diamniotic (MCDA) twin fetuses, who undergone an MRI scan to evaluate growth restriction in the discordant twin (weight < 10^th centile) during 6 years period, at a single tertiary center. Twenty-seven twin pairs were included in the volumetric study and 17 pairs were included in the neurodevelopmental outcome examination. The volumes of the supratentorial brain region, both hemispheres, eyes, and the cerebellum were measured by 3D MRI semi-automated volume measurements. Volumes were plotted on normal growth curves and discordance was compared between weight at birth and brain structure volumes. Neurodevelopmental outcome was evaluated using the VABS-II questionnaire at a mean age of 4.9 years.

RESULTS

The volume of major brain structures was significantly larger in the appropriate-for-gestational-age twins (AGA) compared to the small-for-gestational-age (SGA) co-twins (p < 0.001). The birth weight discordance was 32.3% (24.9-48.6) and was significantly greater (p < 0.001) than the discordance of the prenatal supratentorial brain (13.6% [5.6-18]), cerebellum volume (21.7% [9.5-30.8]). Further neurodevelopmental outcome evaluation found no significant difference between the AGA twin and the SGA twin.

CONCLUSION

In discordant twins, the smaller twin showed a "brain-preserving effect," which in our study was not associated with a worse neurodevelopmental outcome. The use of MRI in such cases may aid in decision-making and parental consultation.

KEY POINTS

• Weight discordance at birth was significantly greater compared to intrauterine brain volume discordance measured by 3D MRI. • Small-for-gestational-age (SGA) fetuses preserve brain development. • In highly discordant twins, there was no long-term difference in neurodevelopmental outcome at a mean age of 4.9 years.

Is ProBNP a New Marker for Predicting Intrauterine Growth Restriction?

PURPOSE

To evaluate the usability of first-trimester maternal serum ProBNP levels in the prediction of intrauterine growth restriction (IUGR). Methods In this prospective study, blood samples taken from 500 women who applied to our polyclinic for routine serum aneuploidy screening between the 11-14th gestational weeks were centrifuged. The obtained plasma samples were placed in Eppendorf tubes and stored at -80+°C. For the final analysis, first-trimester maternal serum ProBNP levels of 32 women diagnosed with postpartum IUGR and 32 healthy women randomly selected as the control group were compared. FGR was defined as estimated fetal weight below the 10th percentile for the gestational age.

RESULTS

The mean ProBNP levels were statistically and significantly higher in the women with intrauterine growth restriction (113.73±94.69 vs. 58.33±47.70 pg/mL, p<0.01). At a cut-off level of 50.93, ProBNP accurately predicted occurrence of IUGR (AUC+= 0.794 (95% confidence interval 0.679-0.910), p+= 0.001) with sensitivity and specificity rates of 78.1 and 69.0%, respectively. Conclusion First-trimester serum ProBNP level was significantly higher in women who developed IUGR compared to healthy controls. First-trimester ProBNP level can be used as a potential marker to predict the development of IUGR in pregnant women.

FIGO (international Federation of Gynecology and obstetrics) initiative on fetal growth: best practice advice for screening, diagnosis, and management of fetal growth restriction

Fetal growth restriction (FGR) is defined as the failure of the fetus to meet its growth potential due to a pathological factor, most commonly placental dysfunction. Worldwide, FGR is a leading cause of stillbirth, neonatal mortality, and short- and long-term morbidity. Ongoing advances in clinical care, especially in definitions, diagnosis, and management of FGR, require efforts to effectively translate these changes to the wide range of obstetric care providers. This article highlights agreements based on current research in the diagnosis and management of FGR, and the areas that need more research to provide further clarification of recommendations. The purpose of this article is to provide a comprehensive summary of available evidence along with practical recommendations concerning the care of pregnancies at risk of or complicated by FGR, with the overall goal to decrease the risk of stillbirth and neonatal mortality and morbidity associated with this condition. To achieve these goals, FIGO (the International Federation of Gynecology and Obstetrics) brought together international experts to review and summarize current knowledge of FGR. This summary is directed at multiple stakeholders, including healthcare providers, healthcare delivery organizations and providers, FIGO member societies, and professional organizations. Recognizing the variation in the resources and expertise available for the management of FGR in different countries or regions, this article attempts to take into consideration the unique aspects of antenatal care in low-resource settings (labelled “LRS” in the recommendations). This was achieved by collaboration with authors and FIGO member societies from low-resource settings such as India, Sub-Saharan Africa, the Middle East, and Latin America.