Can prenatal ultrasound detect the effects of in-utero alcohol exposure? A pilot study

Alcohol exposure before and during pregnancy is associated with reduced fetal growth: the Safe Passage Study

BACKGROUND

Prenatal alcohol exposure (PAE) is a worldwide public health concern. While PAE is known to be associated with low birth weight, little is known about timing and quantity of PAE on fetal growth. This study investigated the association between periconceptional and prenatal alcohol exposure and longitudinal fetal growth, focusing on timing and quantity in a high exposure cohort.

METHODS

The Safe Passage Study was a prospective cohort study, including 1698 pregnant women. Two-dimensional transabdominal ultrasound examinations were performed to measure fetal femur length, abdominal and head circumference, and biparietal diameter, at three time points during pregnancy. Estimated fetal weight and Z-scores of all parameters were calculated. Trimester-specific alcohol exposure was assessed using the Timeline Followback method. To investigate the associations of specific timing of PAE and fetal growth, two models were built. One with alcohol exposure as accumulative parameter over the course of pregnancy and one trimester specific model, in which PAE was separately analyzed. Linear mixed models adjusted for potential confounders were applied with repeated assessments of both alcohol exposure and fetal growth outcomes.

RESULTS

This study demonstrated that periconceptional and prenatal alcohol exposure were associated with reduced fetal growth. Effect sizes are displayed as estimated differences (ED) in Z-score and corresponding 95% confidence intervals (95% CIs). When investigated as accumulative parameter, PAE was related to a smaller femur length (ED30; - 0.13 (95% CI; - 0.22; - 0.04), ED36; - 0.14 (95% CI; - 0.25; - 0.04)) and a smaller abdominal circumference (ED36; - 0.09 (95% CI; - 0.18; - 0.01)). Periconceptional alcohol exposure was associated with a smaller abdominal circumference (ED30; - 0.14 (95% CI; - 0.25; - 0.02), ED36; - 0.22 (95% CI; - 0.37; - 0.06)) and a smaller estimated fetal weight (ED36; - 0.22 (95% CI; - 0.38; - 0.05)). Second trimester alcohol exposure was associated with a smaller abdominal circumference (ED30; - 0.49 (95% CI; - 0.86; - 0.12), ED36; - 0.70 (95% CI; - 1.22; - 0.17)) and estimated fetal weight (ED30; - 0.54 (95% CI; - 0.94; - 0.14), ED36; - 0.69 (95% CI; - 1.25; - 0.14)). No additional association of binge drinking was found besides the already observed association of PAE and fetal growth.

CONCLUSIONS

This study demonstrated that PAE negatively affects fetal growth, in particular when exposed during the periconception period or in second trimester. Our results indicate that potential negative consequences of PAE are detectable already before birth. Therefore, healthcare providers should actively address and discourage alcohol use during pregnancy.

Effects of medications for opioid use disorder (MOUD) on fetal brain and cranial measurements

BACKGROUND

The use and misuse of opioids, as well as opioid use disorder (OUD) have increased remarkably among reproductive-aged and pregnant women. As many as 25% of pregnant women who report non-medical opioid use in the past month also report concurrent alcohol use. While teratogenic effects of alcohol are well established, there are limited studies evaluating fetal intracranial effects associated with medications for OUD (MOUD) and concurrent use of MOUD and alcohol during pregnancy. The objective of this study was to determine the effect of MOUD, with and without concomitant alcohol use, on fetal intracranial measurements. The type of maternal MOUD therapy (methadone vs. buprenorphine) was also examined.

METHODS

This study was a secondary analysis of a prospective cohort study among participants (n = 196) assigned into three groups (MOUD [n = 94], MOUD+Alcohol [n = 47], and unexposed controls [n = 55]). Co-exposure with either methamphetamines or cocaine were exclusionary criteria; other co-exposures were carefully characterized with prospective repeated self-report measures and biomarkers. Fetal ultrasound measurements at 18-22 weeks (2nd trimester) and 28-32 weeks (early 3rd trimester) were compared among study groups. In addition to standard morphometrics, we performed specialized intracranial measurements of caval-calvarial distance (CCD), frontal lobe width (FLW), frontal lobe length (FLL), and fronto-thalamic distance (FTD).

RESULTS

Brain and cranial measurements between MOUD, with or without alcohol co-exposure, and unexposed controls were generally not significantly different in multivariable analyses. Subjects in the MOUD groups had earlier gestational age at delivery and lower birth weight and birth weight percentile compared to unexposed controls with differences driven primarily by the methadone subgroup. Significant differences in standard and specialized intracranial indices at both second and third trimester as well as differences in the change of HC percentile over time were observed in the methadone subgroup compared to controls, while no differences between buprenorphine subgroup and controls were observed for any measures.

CONCLUSION

Patients receiving methadone therapy might require closer monitoring during pregnancy; however, detailed imaging of the fetal brain other than the standard measurements might not be warranted.

The impact of early-life environment on absence epilepsy and neuropsychiatric comorbidities

This review discusses the long-term effects of early-life environment on epileptogenesis, epilepsy, and neuropsychiatric comorbidities with an emphasis on the absence epilepsy. The WAG/Rij rat strain is a well-validated genetic model of absence epilepsy with mild depression-like (dysthymia) comorbidity. Although pathologic phenotype in WAG/Rij rats is genetically determined, convincing evidence presented in this review suggests that the absence epilepsy and depression-like comorbidity in WAG/Rij rats may be governed by early-life events, such as prenatal drug exposure, early-life stress, neonatal maternal separation, neonatal handling, maternal care, environmental enrichment, neonatal sensory impairments, neonatal tactile stimulation, and maternal diet. The data, as presented here, indicate that some early environmental events can promote and accelerate the development of absence seizures and their neuropsychiatric comorbidities, while others may exert anti-epileptogenic and disease-modifying effects. The early environment can lead to phenotypic alterations in offspring due to epigenetic modifications of gene expression, which may have maladaptive consequences or represent a therapeutic value. Targeting DNA methylation with a maternal methyl-enriched diet during the perinatal period appears to be a new preventive epigenetic anti-absence therapy. A number of caveats related to the maternal methyl-enriched diet and prospects for future research are discussed.

Markers of Neuroinflammation in the Serum of Prepubertal Children with Fetal Alcohol Spectrum Disorders

BACKGROUND

Fetal Alcohol Spectrum Disorders (FASD) are the manifestation of the damage caused by alcohol consumption during pregnancy. Children with Fetal Alcohol Syndrome (FAS), the extreme FASD manifestation, show both facial dysmorphology and mental retardation. Alcohol consumed during gestational age prejudices brain development by reducing, among others, the synthesis and release of neurotrophic factors and neuroinflammatory markers. Alcohol drinking also induces oxidative stress.

HYPOTHESIS/OBJECTIVE

The present study aimed to investigate the potential association between neurotrophins, neuroinflammation, and oxidative stress in 12 prepubertal male and female FASD children diagnosed as FAS or partial FAS (pFAS).

METHODS

Accordingly, we analyzed, in the serum, the level of BDNF and NGF and the oxidative stress, as Free Oxygen Radicals Test (FORT) and Free Oxygen Radicals Defense (FORD). Moreover, serum levels of inflammatory mediators (IL-1α, IL-2, IL-6, IL-10, IL-12, MCP-1, TGF-β, and TNF-α) involved in neuroinflammatory and oxidative processes have been investigated.

RESULTS

We demonstrated low serum levels of NGF and BDNF in pre-pubertal FASD children with respect to healthy controls. These changes were associated with higher serum presence of TNF- α and IL-1α. Quite interestingly, an elevation in the FORD was also found despite normal FORT levels. Moreover, we found a potentiation of IL-1α, IL-2, IL-10, and IL-1α1 in the analyzed female compared to male children.

CONCLUSION

The present investigation shows an imbalance in the peripheral neuroimmune pathways that could be used in children as early biomarkers of the deficits observed in FASD.

Fetus morphology changes by second-trimester ultrasound in pregnant women drinking alcohol

Fetal alcohol spectrum disorders (FASDs) are a group of negative conditions occurring in children exposed to alcohol during gestation. The early discovery of FASD is crucial for mother and infant follow-ups. In this study, we investigated in pregnant women the association between urine ethylglucuronide (EtG-a biomarker of alcohol drinking) and indicators of the physical characteristics of FASD by prenatal ultrasound in the second trimester of gestation. We also correlated these data with the AUDIT-C, T-ACE/TACER-3, TWEAK, and food habit diary, screening questionnaires used to disclose alcohol drinking during pregnancy. Forty-four pregnant women were randomly enrolled and examined for ultrasound investigation during the second trimester of gestation. Urine samples were provided by pregnant women immediately after the routine interviews. EtG determinations were performed with a cutoff established at 100 ng/mL, a value indicating occasional alcohol drinking. Fifteen of the enrolled pregnant women overcame the EtG cutoff (34.09%). Analysis of variance (ANOVA) revealed that the fetuses of the positive EtG pregnant women had significantly longer interorbital distance and also significantly increased frontothalamic distance (P's < 0.02). Quite interestingly, no direct correlation was found between EtG data and both food diary and AUDIT-C. However, a significant correlation was observed between urinary EtG and T-ACE (r = 0.375; P = 0.012) and between urinary EtG and TWEAK (r = 0.512; P < 0.001) and a concordance with all questionnaire for EtG values higher than 500 ng/mL. This study provides clinical evidence that the diagnosis of maternal alcohol consumption during pregnancy by urine EtG may disclose FASD-related damage in the fetus.

A methodological review of fetal neurosonographic studies: New directions in assessment of neurodevelopmental risk for mental health problems

Most mental disorders are now considered to have neurodevelopmental origins, with a growing body of research pointing to neural alterations that predate birth. However, lack of established methods for reliable investigation of fetal brain development has limited research into early neural vulnerability. Using a systematic approach and quantitative evaluation of study methodology, we review neurosonographic studies of fetal brain structure with objective quality measures. A total of 81 studies were identified. High quality studies were identified for measurement of the corpus callosum, cerebellum, vermis, ventricles and frontal cortex, with reference ranges provided to facilitate future clinical research. Fewer and lower quality studies were available for subcortical structures, prompting a need for further research to create reliable reference ranges. Development and adoption of reference ranges for fetal brain structures should facilitate future research in neurosonographic evaluation of fetal brain development and lead to a better understanding of neurodevelopmental risk and resilience processes for mental disorders.

Maternal choline supplementation mitigates alcohol-induced fetal cranio-facial abnormalities detected using an ultrasonographic examination in a sheep model

Early detection of prenatal alcohol exposure is critical for designing and testing effectiveness of interventional therapeutics. Choline supplementation during and after prenatal alcohol exposure has shown promising benefits in improving outcomes in rodent models and clinical studies. A sheep model of first trimester-equivalent binge alcohol exposure was used in this study to model the dose of maternal choline supplementation used in an ongoing prospective clinical trial involving pregnancies at risk for FASD. Pregnant sheep were randomly assigned to six groups: Saline + Placebo control, Saline + Choline, binge Alcohol + Placebo (light binging), binge Alcohol + Choline, Heavy binge Alcohol + Placebo (heavy binging), and Heavy binge Alcohol + Choline. Ewes received intravenous alcohol or saline on three consecutive days per week from gestation day (GD) 4-41 to mimic a first trimester-equivalent weekend binge-drinking paradigm. Choline (10 mg/kg in the daily food ration) was administered from GD 4 until term. On GD 76, 11 fetal ultrasonographic measurements were collected transabdominally. Heavy binge alcohol exposure reduced fetal Frontothalamic Distance (FTD), Mean Orbital Diameter (MOD), and Mean Lens Diameter (MLD), and increased Interorbital Distance (IOD) and Thalamic Width (TW). Maternal choline supplementation mitigated most of these alcohol-induced effects. Maternal choline supplementation also improved overall fetal femur and humerus bone lengths, compared to their respective placebo groups. Taken together, these results indicate a potential dose-dependent effect that could impact the sensitivity of these ultrasonographic measures in predicting prenatal alcohol exposure. This is the first study in the sheep model to identify biomarkers of prenatal alcohol exposure in utero with ultrasound and co-administration of maternal choline supplementation.

A systematic review of associations between maternal exposures during pregnancy other than smoking and antenatal fetal measurements

BACKGROUND

Reduced birth weight is associated with many maternal environmental exposures during pregnancy, but the gestational age at onset of this association is unknown. We have previously reported associations between maternal smoking and fetal size.

OBJECTIVE

To report on our systematic review of the literature describing associations between antenatal size and growth and maternal exposures during pregnancy.

DATA SOURCES

Electronic databases (OVID and EMBASE) and web sites for cohort studies were searched. Studies were eligible if they examined associations between maternal environmental exposures (including ambient air exposure, diet and alcohol) and antenatal fetal ultrasound measurements. The Navigation Guide was used to assess the strength of evidence.

RESULTS

There were 451 abstracts identified and 36 papers were included of which maternal diet was the exposure of interest in 15, maternal ambient air exposure in 10, maternal alcohol in 3 and other exposures in 8. The first paper was published in 2006. Associations were present between exposures and fetal measurements in 18% of comparisons with second trimester measurements and in 46% of comparisons with third trimester measurements. In the third trimester, when an association was present, reduced head size was most commonly (58%) associated with current or previous maternal exposure, with reduced length being least commonly (32%) associated and reduced weight being intermediate (52%). In the third trimester, increased maternal nitrogen dioxide exposure was associated with reduced head size was associated with in all seven studies identified and reduced fetal weight in five out of six studies.

CONCLUSION

There is sufficient evidence of toxicity in the context of maternal exposure to nitrogen dioxide and reduced third trimester fetal head size. There is currently insufficient evidence of toxicity with regard to maternal exposures to dietary factors, alcohol and environmental chemicals and reduced fetal size.

Pre-natal brain development as a target for urban air pollution

Air pollution is the main urban-related environmental hazard and one of the major contributors to the global burden of disease based on its cardiovascular-respiratory impacts. In children, exposure to urban air pollution is associated, among others, with decelerated neurodevelopment early in life and increased risk of neurodevelopmental problems such as attention-deficit hyperactivity disorder, autism spectrum disorders, academic failure and the start of Alzheimer's pathogenesis. However, the evidence of the effects of air pollution on brain development is still inadequate, mainly due to the limitations in (a) characterizing brain development (most studies were based on subjective tools such as questionnaires or neuropsychological tests) and (b) air pollution exposure (most studies only used residential levels based on geographical modelling and also overlooking the variation in the mixture of air pollutants as well as the composition and hence toxicity of particulate pollutants in different settings), (c) the lack of studies during the most vulnerable stages of brain development (foetal and early life (first two years post-natally)) and (d) the lack of structural and functional imaging data underlying these effects. In mice, in utero exposure to fine particles was linked to structural brain changes and there is a need to establish the generalizability of these findings in human beings. Though scarce, current evidence in children supports the importance of the pre-natal period as a susceptible window of exposure. Two studies in schoolchildren found that pre-natal air pollution exposure might damage brain structure while exposure during childhood was not linked to any structural alteration. Another study showed that children with higher traffic-related air pollution at school had lower functional integration in key brain networks, but no changes in brain structure, possibly partly because of the time window of air pollution exposure (in utero versus childhood exposure). A key development is to discover the windows of greatest sensitivity of structural brain changes to air pollution exposure by incorporating the recent advances in non-invasive imaging to characterize natal and post-natal brain development and exploring whether and to what extend placental dysfunction could mediate such an association. Studying pre-natal life is important because effects at this time are of a potentially irreversible nature and because the largest preventive opportunities occur during these periods.

Asymmetric neonatal spasms as an early sign of brain malformation potentially caused by regular light alcohol consumption during the first 22 weeks of pregnancy, a clinical case report

OBJECTIVE

Introduction: Epileptic spasms are seizures usually associated with a severe developmental epilepsy syndrome with onset in the first year of life, peaking between 3 and 10 months of age [12]. A variety of disorders can cause epileptic spasms, with the etiology driving management, prognosis, and overall outcome. Preexisting brain damage has been demonstrated in 60% to 90% of the cases reflecting pre-, peri-, or postnatal brain injury that may usually be determined by history and clinical neurologic examination. Cerebral malformations may account for up to 30% of the cases [2]. Prenatal alcohol exposure can permanently damage the brain, affecting important structures, such as the cerebellum, corpus callosum as well as specific cell populations in many other regions of the brain. No one knows what a "safe" amount of alcohol consumption during pregnancy may be[3]. Objective: The aim of this article is to present a clinical case of a large brain temporal lobe malformation which was recognized after a very early onset of spasms registered on video EEG-monitoring followed by MRI findings and to put forward the assumption that regular consumption of light alcoholic drinks even in low doses could contribute to irreversible brain damage in the fetus.

PATIENTS AND METHODS

Material and methods: All patient data were collected from the NICU and Newborn Pathology Department of Lviv City Children's Clinical Hospital Health Record Department, and included the hospital and clinic records by the staff neurologist, neurophysiologist, and pediatrician, as well as EEG records in the postneonatal period. The mother was interviewed to clarify the pregnancy course data. The mother's consent was obtained for publication.

RESULTS

Results: Asymmetric spasms, which were recognized as seizures on the 4th day of the child's life while recording video EEG, urged the physicians towards further diagnostic investigations. Primarily the child was diagnosed with neonatal abstinence syndrome on the 2nd day of life based on clinical and patient history data, but on the following day episodes of myoclonic jerks and jitteriness were noticed and video EEG monitoring started. Upon analysis of video- EEG, myoclonic seizures and spasms were reported showing asymmetry in the amplitude of ictal EEG. MRI was recommended and performed to explain focal EEG findings, and a large brain left temporal lobe malformation was seen.

CONCLUSION

Conclusions: Spasms in the form of seizures are rarely reported in the neonatal period. Their recognition has to lead to urgent brain imaging study to look for the underlying cause and to implement timely, appropriate corrections in the treatment strategy. Although brain malformations can have many causes, taking careful antenatal, perinatal and family history has ruled out many usual etiologies. Maternal alcohol consumption during pregnancy may potentially have contributed to the condition.

Maternal exposure to ambient air pollution and fetal growth in North-East Scotland: A population-based study using routine ultrasound scans

BACKGROUND

Maternal ambient air pollution exposure is associated with reduced birthweight. Few studies have examined the effect on growth in utero and none have examined the effect of exposure to particulates less than 2.5µm (PM_2.5) and possible effect modification by smoking status.

OBJECTIVES

Examine the effect of maternal exposure to ambient concentrations of PM₁₀, PM_2.5 and nitrogen dioxide (NO₂) for in utero fetal growth, size at birth and effect modification by smoking status.

METHODS

Administratively acquired second and third trimester fetal measurements (bi-parietal diameter, femur length and abdominal circumference), birth outcomes (weight, crown heel length and occipito-frontal circumference) and maternal details were obtained from routine fetal ultrasound scans and maternity records (period 1994-2009). These were modelled against residential annual pollution concentrations (calendar year mean) adjusting for covariates and stratifying by smoking status.

RESULTS

In the whole sample (n=13,775 pregnancies), exposure to PM₁₀, PM_2.5 and NO₂ was associated with reductions in measurements at birth and biparietal diameter from late second trimester onwards. Among mothers who did not smoke at all during pregnancy (n=11,075), associations between biparietal diameter and pollution exposure remained significant but were insignificant among those who did smoke (n=2700). Femur length and abdominal circumference were not significantly associated with pollution exposure.

CONCLUSIONS

Fetal growth is strongly associated with particulates exposure from later in second trimester onwards but the effect appears to be subsumed by smoking. Typical ambient exposures in this study were relatively low compared to other studies and given these results, it may be necessary to consider reducing recommended "safe" ambient air exposures.

Radiological studies of fetal alcohol spectrum disorders in humans and animal models: An updated comprehensive review

Fetal Alcohol Spectrum Disorders encompass a wide range of birth defects in children born to mothers who consumed alcohol during pregnancy. Typical mental impairments in FASD include difficulties in life adaptation and learning and memory, deficits in attention, visuospatial skills, language and speech disabilities, mood disorders and motor disabilities. Multimodal imaging methods have enabled in vivo studies of the teratogenic effects of alcohol on the central nervous system, giving more insight into the FASD phenotype. This paper offers an up-to-date comprehensive review of radiological findings in the central nervous system in studies of prenatal alcohol exposure in both humans and translational animal models, including Magnetic Resonance Imaging, Computed Tomography, Positron Emission Tomography, Single Photon Emission Tomography and Ultrasonography.

A Novel Approach to Prenatal Measurement of the Fetal Frontal Lobe Using Three-Dimensional Sonography

OBJECTIVE

While prenatal 3D ultrasonography results in improved diagnostic accuracy, no data are available on biometric assessment of the fetal frontal lobe. This study was designed to assess feasibility of a standardized approach to biometric measurement of the fetal frontal lobe and to construct frontal lobe growth trajectories throughout gestation.

STUDY DESIGN

A sonographic 3D volume set was obtained and measured in 101 patients between 16.1 and 33.7 gestational weeks. Measurements were obtained by two independent raters. To model the relationship between gestational age and each frontal lobe measurement, flexible linear regression models were fit using penalized regression splines.

RESULTS

The sample contained an ethnically diverse population (7.9% Native Americans, 45.5% Hispanic/Latina). There was high inter-rater reliability (correlation coefficients: 0.95, 1.0, and 0.87 for frontal lobe length, width, and height; p-values < 0.001). Graphs of the growth trajectories and corresponding percentiles were estimated as a function of gestational age. The estimated rates of frontal lobe growth were 0.096 cm/week, 0.247 cm/week, and 0.111 cm/week for length, width, and height.

CONCLUSION

To our knowledge, this is the first study to examine fetal frontal lobe growth trajectories through 3D prenatal ultrasound examination. Such normative data will allow for future prenatal evaluation of a particular disease state by 3D ultrasound imaging.

A systematic review of maternal smoking during pregnancy and fetal measurements with meta-analysis

BACKGROUND

Maternal smoking during pregnancy is linked to reduced birth weight but the gestation at onset of this relationship is not certain. We present a systematic review of the literature describing associations between maternal smoking during pregnancy and ultrasound measurements of fetal size, together with an accompanying meta-analysis.

METHODS

Studies were selected from electronic databases (OVID, EMBASE and Google Scholar) that examined associations between maternal smoking or smoke exposure and antenatal fetal ultrasound measurements. Outcome measures were first, second or third trimester fetal measurements.

RESULTS

There were 284 abstracts identified, 16 papers were included in the review and the meta-analysis included data from eight populations. Maternal smoking was associated with reduced second trimester head size (mean reduction 0.09 standard deviation (SD) [95% CI 0.01, 0.16]) and femur length (0.06 [0.01, 0.10]) and reduced third trimester head size (0.18 SD [0.13, 0.23]), femur length (0.27 SD [0.21, 0.32]) and estimated fetal weight (0.18 SD [0.11, 0.24]). Higher maternal cigarette consumption was associated with a lower z score for head size in the second (mean difference 0.09 SD [0, 0.19]) and third (0.15 SD [0.03, 0.26]) trimesters compared to lower consumption. Fetal measurements were not reduced for those whose mothers quit before or after becoming pregnant compared to mothers who had never smoked.

CONCLUSIONS

Maternal smoking during pregnancy is associated with reduced fetal measurements after the first trimester, particularly reduced head size and femur length. These effects may be attenuated if mothers quit or reduce cigarette consumption during pregnancy.

Impacts on prenatal development of the human cerebellum: a systematic review

PURPOSE

The cerebellum is essential for normal neurodevelopment and is particularly susceptible for intra-uterine disruptions. Although some causal prenatal exposures have been identified, the origin of neurodevelopmental disorders remains mostly unclear. Therefore, a systematic literature search was conducted to provide an overview of parental environmental exposures and intrinsic factors influencing prenatal cerebellar growth and development in humans.

MATERIALS AND METHODS

The literature search was limited to human studies in the English language and was conducted in Embase, Medline, Cochrane, Web of Science, Pubmed and GoogleScholar. Eligible studies were selected by three independent reviewers and study quality was scored by two independent reviewers.

RESULTS

The search yielded 3872 articles. We found 15 eligible studies reporting associations between cerebellar development and maternal smoking (4), use of alcohol (3), in vitro fertilization mediums (1), mercury (1), mifepristone (2), aminopropionitriles (1), ethnicity (2) and cortisol levels (1). No studies reported on paternal factors.

CONCLUSIONS

Current literature on associations between parental environmental exposures, intrinsic factors and human cerebellar development is scarce. Yet, this systematic review provided an essential overview of human studies demonstrating the vulnerability of the cerebellum to the intra-uterine environment.

Cardiac Orienting Responses Differentiate the Impact of Prenatal Alcohol Exposure in Ukrainian Toddlers

BACKGROUND

Prenatal alcohol exposure (PAE) has been found to impact neurophysiological encoding of environmental events negatively in the first year of life but has not been evaluated in older infants or toddlers. Cardiac orienting responses (ORs) collected during a habituation/dishabituation learning paradigm were obtained from 12- to 18-month-olds to assess the impact of PAE beyond the first year of life.

METHODS

Participants included women and their toddlers who differed in PAE histories and enrolled in a randomized clinical trial of multivitamin/mineral usage during pregnancy. Those who were randomly assigned to the no intervention group were used for this analysis. The habituation/dishabituation paradigm consisted of 10 habituation and 5 dishabituation trials. Baseline heart rate (HR) was collected for 30 seconds prior to stimulus onset, and responses to the stimuli were assessed by sampling HR for 12 seconds poststimulus onset.

RESULTS

The speed of the OR in response to auditory stimuli in the dishabituation condition was found to be altered as a function of maternal alcohol use around conception. For visual stimuli, positive histories of PAE were predictive of the magnitude but not the speed of the response on habituation and dishabituation trials. A history of binge drinking was associated with reduced magnitude of the OR response on visual encoding trials, and level of alcohol exposure at the time of conception was predictive of the magnitude of the response on visual dishabituation trials.

CONCLUSIONS

Cardiac ORs collected in the toddler period were sensitive to the effects of PAE. The magnitude of the OR was more sensitive to the impact of PAE than in previous research with younger infants, and this may be a function of brain maturation. Additional research assessing the predictive utility of using ORs in making decisions about individual risk was recommended.

A review of the physical features of the fetal alcohol spectrum disorders

The fetal alcohol spectrum of disorders (FASD) includes four diagnostic categories for the clinical consequences of prenatal alcohol exposure (PAE) in the unborn child. Physical features are necessary for the diagnosis of the fetal alcohol syndrome (FAS) and partial pFAS. Moreover, these features are specific and a diagnosis of FAS can be made even in the absence of knowledge of PAE. Not only growth deficits, microcephaly and the 3 facial features (short palpebral fissures, smooth philtrum and narrow vermillion of the upper lip) are characteristic, since other dysmorphic features particularly in the hands are key to the recognition of FAS. Most features can be explained by the damage to the brain during pregnancy and can be replicated in animal models. Many different diagnostic guidelines are used for the diagnosis of FASD and the physical features are considered differently in each of them. There is a need for universal clinical criteria for the diagnosis of FASD if our goal is to favor universal recognition.

Second-Trimester Ultrasound as a Tool for Early Detection of Fetal Alcohol Spectrum Disorders

BACKGROUND

Early detection of fetal alcohol spectrum disorders (FASDs) is desirable to allow earlier and more comprehensive interventions to be initiated for the mother and infant. We examined prenatal ultrasound as an early method of detecting markers of the physical features and neurobehavioral deficits characteristic of FASD.

METHODS

A longitudinal cohort of pregnant women in Ukraine was recruited as part of the Collaborative Initiative on Fetal Alcohol Spectrum Disorders. Women were enrolled into a moderately to heavy-alcohol-exposed group or a low- or no-alcohol exposure group and were followed to pregnancy outcome. In the second trimester, a fetal ultrasound was performed to measure transverse cerebellar diameter, occipital frontal diameter (OFD), caval-calvarial distance, frontothalamic distance (FTD), interorbital distance (IOD), outer orbital diameter, and orbital diameter (OD). Live born infants received a dysmorphological examination and a neurobehavioral evaluation using the Bayley Scales of Infant Development. These data were used to classify infants with respect to FASD. Comparisons were made on the ultrasound measures between those with and without features of FASD, adjusting for gestational age at ultrasound and maternal smoking.

RESULTS

A total of 233 mother/child dyads were included. Children classified as FASD had significantly longer IOD and lower FTD/IOD, OFD/IOD, and FTD/OD ratios (p < 0.05). Children with a Bayley score <85 had significantly shorter FTD, longer IOD, lower OFD/IOD, and FTD/IOD ratios (p < 0.05). In general, mean differences were small. Ultrasound variables alone predicted <10% of the variance in the FASD outcome.

CONCLUSIONS

Some ultrasound measurements were associated with FASD, selected facial features of the disorder, and lower neurobehavioral scores. However, mean differences were relatively small, making it difficult to predict affected children based solely on these measures. It may be advantageous to combine these easily obtained ultrasound measures with other data to aid in identifying high risk for an FASD outcome.

Fetal alcohol-spectrum disorders: identifying at-risk mothers

Fetal alcohol-spectrum disorders (FASDs) are a collection of physical and neurobehavioral disabilities caused by prenatal exposure to alcohol. To prevent or mitigate the costly effects of FASD, we must identify mothers at risk for having a child with FASD, so that we may reach them with interventions. Identifying mothers at risk is beneficial at all time points, whether prior to pregnancy, during pregnancy, or following the birth of the child. In this review, three approaches to identifying mothers at risk are explored: using characteristics of the mother and her pregnancy, using laboratory biomarkers, and using self-report assessment of alcohol-consumption risk. At present, all approaches have serious limitations. Research is needed to improve the sensitivity and specificity of biomarkers and screening instruments, and to link them to outcomes as opposed to exposure. Universal self-report screening of all women of childbearing potential should ideally be incorporated into routine obstetric and gynecologic care, followed by brief interventions, including education and personalized feedback for all who consume alcohol, and referral to treatment as indicated. Effective biomarkers or combinations of biomarkers may be used during pregnancy and at birth to determine maternal and fetal alcohol exposure. The combination of self-report and biomarker screening may help identify a greater proportion of women at risk for having a child with FASD, allowing them to access information and treatment, and empowering them to make decisions that benefit their children.

Maternal drug or alcohol abuse is associated with decreased head size from mid-pregnancy to childhood

AIM

Maternal alcohol abuse is poorly recognised and causes developmental problems. This study explored the foetal central nervous systems (CNS), head circumference and psychomotor development of children exposed to drugs or alcohol during pregnancy up to 2.5 years of age.

METHODS

We recruited 23 pregnant women referred to Kuopio University Hospital, Finland, by their family doctor because of drug or alcohol abuse, and 22 control mothers. Foetal CNS parameters were measured by three-dimensional ultrasonography at the mean gestational age of 20 weeks and the Griffiths Mental Developmental Scales (GMDS), and anthropometric measurements were carried out at the mean ages of one and 2.5 years.

RESULTS

The exposed foetuses had decreased biparietal and occipito-frontal distances and head circumferences, but unchanged cerebellar volume at 20 weeks, and decreased head circumferences and length and height at birth, one and 2.5 years of age. They scored lower than the controls on the GMDS general quotient and the hearing, language and locomotor subscales at 2.5 years of age.

CONCLUSION

Maternal alcohol or drug exposure was associated with decreased head size from mid-pregnancy to childhood and reduced development at 2.5 years. Foetal head circumference at mid-pregnancy was a useful indicator of substance abuse affecting the CNS.

Dysmorphogenic effects of first trimester-equivalent ethanol exposure in mice: a magnetic resonance microscopy-based study

BACKGROUND

The first trimester of human development and the equivalent developmental period in animal models is a time when teratogenic ethanol (EtOH) exposure induces the major structural birth defects that fall within fetal alcohol spectrum disorder (FASD). Previous FASD research employing an acute high dose maternal intraperitoneal EtOH treatment paradigm has identified sensitive periods for a number of these defects. Extending this work, this investigation utilized high resolution magnetic resonance microscopy (MRM)-based analyses to examine the dysmorphology resulting from maternal dietary EtOH intake occurring during selected first trimester-equivalent time periods.

METHODS

Female C57Bl/6J mice were acclimated to a liquid 4.8% EtOH (v/v)-containing diet, then bred while on standard chow. Dams were again provided the EtOH-containing liquid diet for a period that extended either from the beginning of gestational day (GD) 7 to the end of GD 11 or from the beginning of GD 12 to the end of GD 16. On GD 17, a subset of fetuses was selected for MRM-based analyses. Group comparisons were made for litter characteristics and gross dysmorphology, as well as whole and regional brain volumes.

RESULTS

EtOH-induced stage of exposure-dependent structural brain abnormalities were observed. The GD 7 to 11 EtOH-exposed group presented with a significant decrease in cerebellar volume and an increase in septal volume, while GD 12 to 16 EtOH treatment resulted in a reduction in right hippocampal volume accompanied by enlarged pituitaries. Additionally, the GD 12 to 16 EtOH exposure caused a high incidence of edema/fetal hydrops.

CONCLUSIONS

These results illustrate the teratogenic impact of maternal dietary EtOH intake occurring at time periods approximately equivalent to weeks 3 through 6 (GD 7 to 11 in mice) and weeks 7 through 12 (GD 12 to 16 in mice) of human gestation, further documenting EtOH's stage of exposure-dependent neuroteratogenic end points and highlighting the vulnerability of selected brain regions during the first trimester. Additionally they suggest that clinical attention should be paid to fetal hydrops as a likely component of FASD.

Fetal alcohol spectrum disorders and neuroimmune changes

The behavioral consequences of fetal alcohol spectrum disorders (FASD) are serious and persist throughout life. The causative mechanisms underlying FASD are poorly understood. However, much has been learned about FASD from human structural and functional studies as well as from animal models, which have provided a greater understanding of the mechanisms underlying FASD. Using animal models of FASD, it has been recently discovered that ethanol induces neuroimmune activation in the developing brain. The resulting microglial activation, production of proinflammatory molecules, and alteration in expression of developmental genes are postulated to alter neuron survival and function and lead to long-term neuropathological and cognitive defects. It has also been discovered that microglial loss occurs, reducing microglia's ability to protect neurons and contribute to neuronal development. This is important, because emerging evidence demonstrates that microglial depletion during brain development leads to long-term neuropathological and cognitive defects. Interestingly, the behavioral consequences of microglial depletion and neuroimmune activation in the fetal brain are particularly relevant to FASD. This chapter reviews the neuropathological and behavioral abnormalities of FASD and delineates correlates in animal models. This serves as a foundation to discuss the role of the neuroimmune system in normal brain development, the consequences of microglial depletion and neuroinflammation, the evidence of ethanol induction of neuroinflammatory processes in animal models of FASD, and the development of anti-inflammatory therapies as a new strategy for prevention or treatment of FASD. Together, this knowledge provides a framework for discussion and further investigation of the role of neuroimmune processes in FASD.

Magnetic resonance microscopy-based analyses of the neuroanatomical effects of gestational day 9 ethanol exposure in mice

Animal model-based studies have shown that ethanol exposure during early gestation induces developmental stage-specific abnormalities of the face and brain. The exposure time-dependent variability in ethanol's teratogenic outcomes is expected to contribute significantly to the wide spectrum of effects observed in humans with fetal alcohol spectrum disorder (FASD). The work presented here employs a mouse FASD model and magnetic resonance microscopy (MRM; high resolution magnetic resonance imaging) in studies designed to further our understanding of the developmental stage-specific defects of the brain that are induced by ethanol. At neurulation stages, i.e. at the beginning of gestational day (GD) 9 and again 4 hours later, time-mated C57Bl/6J dams were intraperitoneally administered 2.9 g/kg ethanol or vehicle. Ethanol-exposed fetuses were collected on GD 17, processed for MRM analysis, and results compared to comparably staged controls. Linear and volume measurements as well as shape changes for numerous individual brain regions were determined. GD 9 ethanol exposure resulted in significantly increased septal region width, reduction of cerebellar volume, and enlargement of all of the ventricles. Additionally, the results of shape analyses showed that many areas of the ethanol-exposed brains including the cerebral cortex, hippocampus and right striatum were significantly misshapen. These data demonstrate that ethanol can induce dysmorphology that may not be obvious based on volumetric analyses alone, highlight the asymmetric aspects of ethanol-induced defects, and add to our understanding of ethanol's developmental stage-dependent neuroteratogenesis.

Fetal alcohol spectrum disorders and fetal alcohol syndrome: the state of the art and new diagnostic tools

Ethanol consumption during pregnancy is a widespread problem which is increasing in the generation of young women. Gestational alcohol consumption causes fetal exposure to this teratogen and is associated with the onset of fetal alcohol spectrum disorders (FASD) including fetal alcohol syndrome (FAS). FASD and FAS can lead to several physical, cognitive and behavioral disabilities, whose early diagnosis is of primary importance to perform primary prevention with total abstinence from alcohol during pregnancy and secondary prevention in newborns and children for a proper follow up to reduce risk of secondary consequences. In recent years significant efforts have been made to understand the underlying mechanisms of this disease and to identify objective biological and instrumental diagnostic tools, such as exposure biomarkers in neonatal meconium and advanced magnetic resonance imaging. Nonetheless, further studies are still needed to implement our knowledge on fetal effects of ethanol, and multidisciplinary actions are necessary to raise awareness among women of childbearing age about the danger of consuming even small amounts of ethanol during pregnancy.

Ethanol exposure during pregnancy persistently attenuates cranially directed blood flow in the developing fetus: evidence from ultrasound imaging in a murine second trimester equivalent model

BACKGROUND

Ethanol (EtOH) consumption during pregnancy can lead to fetal growth retardation, mental retardation, and neurodevelopmental delay. The fetal brain initiates neurogenesis and vasculogenesis during the second trimester, and depends on maternal-fetal circulation for nutrition and growth signals. We used high-resolution in vivo ultrasound imaging to test the hypothesis that EtOH interferes with fetal brain-directed blood flow during this critical developmental period.

METHODS

Pregnant mice were lightly anesthetized on gestational day 12 with an isoflurane/oxygen mixture. We assessed the effect of single and repeated binge-like maternal EtOH exposures at 3 g/kg, administered by intragastric gavage or intraperitoneal injection, on maternal circulation and fetal umbilical, aortic, internal carotid, and middle cerebral arterial circulation.

RESULTS

Binge maternal EtOH exposure, regardless of exposure route, significantly reduced fetal arterial blood acceleration and velocity time integral (VTI), from umbilical to cerebral arteries, without a change in fetal heart rate and resistivity indices. Importantly a single maternal binge EtOH exposure induced persistent suppression of fetal arterial VTI for at least 24 hours. Repeated binge episodes resulted in a continuing and persistent suppression of fetal VTI. Qualitative assessments showed that maternal EtOH exposure induced oscillatory, nondirectional blood flow in fetal cerebral arteries. Maternal cardiac and other physiological parameters remained unaltered.

CONCLUSIONS

These data show that binge-type maternal EtOH exposure results in rapid and persistent loss of blood flow from the umbilical artery to the fetal brain, potentially compromising nutrition and the maternal/fetal endocrine environment during a critical period for neuron formation and angiogenesis in the maturing brain.

Magnetic resonance-based imaging in animal models of fetal alcohol spectrum disorder

Magnetic resonance imaging (MRI) techniques, such as magnetic resonance microscopy (MRM), diffusion tensor imaging (DTI), and magnetic resonance spectroscopy (MRS), have recently been applied to the study of both normal and abnormal structure and neurochemistry in small animals. Herein, findings from studies in which these methods have been used for the examination of animal models of Fetal Alcohol Spectrum Disorder (FASD) are discussed. Emphasis is placed on results of imaging studies in fetal and postnatal mice that have highlighted the developmental stage dependency of prenatal ethanol exposure-induced CNS defects. Consideration is also given to the promise of methodological advances to allow in vivo studies of aberrant brain and behavior relationships in model animals and to the translational nature of this work.

Focus on: magnetic resonance-based studies of fetal alcohol spectrum disorders in animal models

The imaging techniques magnetic resonance imaging (MRI), diffusion tensor imaging (DTI), and magnetic resonance spectroscopy (MRS) provide valuable tools for studying brain structure and neurochemistry in fetal alcohol spectrum disorders (FASD). Although the application of magnetic resonance-based methodologies to the study of FASD in animal models is in its infancy, it already has provided new clinically relevant insights and holds significant promise to further extend our understanding of alcohol's effects on the developing fetus.

Implementation of a shared data repository and common data dictionary for fetal alcohol spectrum disorders research

Many previous attempts by fetal alcohol spectrum disorders researchers to compare data across multiple prospective and retrospective human studies have failed because of both structural differences in the collected data and difficulty in coming to agreement on the precise meaning of the terminology used to describe the collected data. Although some groups of researchers have an established track record of successfully integrating data, attempts to integrate data more broadly among different groups of researchers have generally faltered. Lack of tools to help researchers share and integrate data has also hampered data analysis. This situation has delayed improving diagnosis, intervention, and treatment before and after birth. We worked with various researchers and research programs in the Collaborative Initiative on Fetal Alcohol Spectrum Disorders (CI-FASD) to develop a set of common data dictionaries to describe the data to be collected, including definitions of terms and specification of allowable values. The resulting data dictionaries were the basis for creating a central data repository (CI-FASD Central Repository) and software tools to input and query data. Data entry restrictions ensure that only data that conform to the data dictionaries reach the CI-FASD Central Repository. The result is an effective system for centralized and unified management of the data collected and analyzed by the initiative, including a secure, long-term data repository. CI-FASD researchers are able to integrate and analyze data of different types, using multiple methods, and collected from multiple populations, and data are retained for future reuse in a secure, robust repository.

Magnetic resonance microscopy-based analyses of the brains of normal and ethanol-exposed fetal mice

BACKGROUND

The application of magnetic resonance microscopy (MRM) to the study of normal and abnormal prenatal mouse development has facilitated discovery of dysmorphology following prenatal ethanol insult. The current analyses extend this work, providing a regional brain volume-based description of normal brain growth and illustrating the consequences of gestational day (GD) 10 ethanol exposure in the fetal mouse.

METHODS

To assess normal growth, control C57Bl/6J fetuses collected on GD 16, GD 16.5, and GD 17 were scanned using a 9.4-T magnet, resulting in 29-μm isotropic resolution images. For the ethanol teratogenicity studies, C57Bl/6J dams were administered intraperitoneal ethanol (2.9 g/kg) at 10 days, 0 hr, and 10 days, 4 hr, after fertilization, and fetuses were collected for analyses on GD 17. From individual MRM scans, linear measurements and regional brain volumes were determined and compared.

RESULTS

In control fetuses, each of the assessed brain regions increased in volume, whereas ventricular volumes decreased between GD 16 and GD 17. Illustrating a global developmental delay, prenatal ethanol exposure resulted in reduced body volumes, crown-rump lengths, and a generalized decrease in regional brain volumes compared with GD 17 controls. However, compared with GD 16.5, morphologically matched controls, ethanol exposure resulted in volume increases in the lateral and third ventricles as well as a disproportionate reduction in cortical volume.

CONCLUSIONS

The normative data collected in this study facilitate the distinction between GD 10 ethanol-induced developmental delay and frank dysmorphology. This work illustrates the utility of MRM-based analyses for developmental toxicology studies and extends our knowledge of the stage-dependency of ethanol teratogenesis.

Magnetic resonance microscopy defines ethanol-induced brain abnormalities in prenatal mice: effects of acute insult on gestational day 7

BACKGROUND

This magnetic resonance microscopy (MRM)-based report is the second in a series designed to illustrate the spectrum of craniofacial and central nervous system (CNS) dysmorphia resulting from single- and multiple-day maternal ethanol treatment. The study described in this report examined the consequences of ethanol exposure on gestational day (GD) 7 in mice, a time in development when gastrulation and neural plate development begins; corresponding to the mid- to late third week postfertilization in humans. Acute GD 7 ethanol exposure in mice has previously been shown to result in CNS defects consistent with holoprosencephaly (HPE) and craniofacial anomalies typical of those in Fetal Alcohol Syndrome (FAS). MRM has facilitated further definition of the range of GD 7 ethanol-induced defects.

METHODS

C57Bl/6J female mice were intraperitoneally (i.p.) administered vehicle or 2 injections of 2.9 g/kg ethanol on day 7 of pregnancy. Stage-matched control and ethanol-exposed GD 17 fetuses selected for imaging were immersion fixed in a Bouins/Prohance solution. MRM was conducted at either 7.0 Tesla (T) or 9.4 T. Resulting 29 microm isotropic spatial resolution scans were segmented and reconstructed to provide 3D images. Linear and volumetric brain measures, as well as morphological features, were compared for control and ethanol-exposed fetuses. Following MRM, selected specimens were processed for routine histology and light microscopic examination.

RESULTS

Gestational day 7 ethanol exposure resulted in a spectrum of median facial and forebrain deficiencies, as expected. This range of abnormalities falls within the HPE spectrum; a spectrum for which facial dysmorphology is consistent with and typically is predictive of that of the forebrain. In addition, other defects including median facial cleft, cleft palate, micrognathia, pituitary agenesis, and third ventricular dilatation were identified. MRM analyses also revealed cerebral cortical dysplasia/heterotopias resulting from this acute, early insult and facilitated a subsequent focused histological investigation of these defects.

CONCLUSIONS

Individual MRM scans and 3D reconstructions of fetal mouse brains have facilitated demonstration of a broad range of GD 7 ethanol-induced morphological abnormality. These results, including the discovery of cerebral cortical heterotopias, elucidate the teratogenic potential of ethanol insult during the third week of human prenatal development.