First Insight into Fetal Exposure to Legacy and Emerging Plasticizers Revealed by Infant Hair and Meconium: Occurrence, Biotransformation, and Accumulation

Epidemiological studies have demonstrated the embryonic and developmental toxicity of plasticizers. Thus, understanding the in utero biotransformation and accumulation of plasticizers is essential to assessing their fate and potential toxicity in early life. In the present study, 311 infant hair samples and 271 paired meconium samples were collected at birth in Guangzhou, China, to characterize fetal exposure to legacy and emerging plasticizers and their metabolites. Results showed that most of the target plasticizers were detected in infant hair, with medians of 9.30, 27.6, and 0.145 ng/g for phthalate esters (PAEs), organic phosphate ester (OPEs), and alternative plasticizers (APs), and 1.44, 0.313, and 0.066 ng/g for the metabolites of PAEs, OPEs, and APs, respectively. Positive correlations between plasticizers and their corresponding primary metabolites, as well as correlations among the oxidative metabolites of bis(2-ethylhexyl) phthalate (DEHP) and 1,2-cyclohexane dicarboxylic acid diisononyl ester (DINCH), were observed, indicating that infant hair retained the major phase-I metabolism of the target plasticizers. While no positive correlations were found in parent compounds or their primary metabolites between paired infant hair and meconium, significant positive correlations were observed among secondary oxidative metabolites of DEHP and DINCH in hair and meconium, suggesting that the primary metabolites in meconium come from hydrolysis of plasticizers in the fetus but most of the oxidative metabolites come from maternal-fetal transmission. The parent compound/metabolite ratios in infant hair showed a decreasing trend across pregnancy, suggesting in utero accumulation and deposition of plasticizers. To the best of our knowledge, this study is the first to report in utero exposure to both parent compounds and metabolites of plasticizers by using paired infant hair and meconium as noninvasive biomonitoring matrices and provides novel insights into the fetal biotransformation and accumulation of plasticizers across pregnancy.

Delay in the fine-tuning of locomotion in infants with meconium positive to biomarkers of alcohol exposure: a pilot study

INTRODUCTION

Prenatal alcohol exposure causes a variety of impairments to the fetus called Fetal Alcohol Spectrum Disorders (FASD). Since it is very difficult to identify women that consume alcohol during pregnancy, different methods have been studied to evaluate alcohol exposure. Ethyl Glucuronide (EtG) and Fatty Acid Ethyl Esters (FAEEs) are commonly used to measure alcohol consumption in individuals at-risk for alcohol abuse, including pregnant women.

MATERIALS AND METHODS

We conducted a study of two cohorts of 1.5 year-old infants (of mothers without a history of alcohol abuse) with or without meconium samples positive to both EtG and FAEEs and we evaluated their cognitive-behavioral development by the Griffiths Mental Developmental Scale (GMDS) method. Our protocol included 8 infants with meconium positive to alcohol metabolites (EtG and FAEEs) and 7 with meconium negative to alcohol metabolites.

RESULTS

None of the 8 alcohol metabolites positive meconium infants exhibited distinctive facial features and growth retardation of severe FASD, showing that other factors may contribute to the FASD onset but elevations in EtG and FAEEs in the meconium were significantly associated with disrupted neurodevelopment and adaptive functions within the first year and a half of life. Indeed, we found out that infants with meconium positive for both EtG and FAEEs, although without displaying any FASD morphological features, had a delay in the fine regulation of their own locomotory capabilities.

CONCLUSIONS

Further analyses and larger studies are needed to estimate the right link between prenatal alcohol exposure and the different range of disorders connected but this study provides an additional step in the field of FASD in order to suggest early treatments for at-risk newborns and infants.

Assessment of Fetal Exposure and Elimination of Perfluoroalkyl and Polyfluoroalkyl Substances: New Evidence from Paired Serum, Placenta, and Meconium Samples

Multiple pieces of evidence have shown that prenatal exposure to perfluoroalkyl and polyfluoroalkyl substances (PFASs) is closely related to adverse birth outcomes for infants. However, difficult access to human samples limits our understanding of PFASs transport and metabolism across the human placental barrier, as well as the accurate assessment of fetal PFASs exposure. Herein, we assess fetal exposure to 28 PFASs based on paired serum, placenta, and meconium samples. Overall, 21 PFASs were identified first to be exposed to the fetus prenatally and to be metabolized and excreted by the fetus. In meconium samples, 25 PFASs were detected, with perfluorooctane sulfonate and perfluorohexane sulfonic acid being the dominant congeners, suggesting the metabolism and excretion of PFASs through meconium. Perfluoroalkyl sulfonic acids might be more easily eliminated through the meconium than perfluorinated carboxylic acids. Importantly, based on molecular docking, MRP1, OATP2B1, ASCT1, and P-gp were identified as crucial transporters in the dynamic placental transfer of PFASs between the mother and the fetus. ATSC5p and PubchemFP679 were recognized as critical structural features that affect the metabolism and secretion of PFASs through meconium. With increasing carbon chain length, both the transplacental transfer efficiency and meconium excretion efficiency of PFASs showed a structure-dependent manner. This study reports, for the first time, that meconium, which is a noninvasive and stable biological matrix, can be strong evidence of prenatal PFASs exposure.

Meconium Transferrin and Ferritin as Markers of Homeostasis in the Developing Fetus

The molecular mechanisms regulating homeostasis in the developing fetus have not been satisfactorily elucidated. Meconium contains substances accumulated in the fetal intestines. Measurements of transferrin and ferritin concentrations in meconium and assessment of transferrin-ferritin relationships could enhance knowledge about specific processes of the intrauterine period involving the two proteins and their effects on the development and growth of the fetus. Transferrin and ferritin concentrations were measured by ELISA in the homogenates of first meconium portions from 125 neonates. Higher birth weight was associated with lower ferritin concentrations in meconium (r = -0.22, p = 0.015). In neonates with a birth weight of more than 3750 g, there was a positive correlation between transferrin and ferritin concentrations (r = 0.51, p = 0.003). With meconium transferrin concentrations above 43.52 µg/g, a negative correlation between transferrin and ferritin was established (r = -0.37, p = 0.036), while with transferrin concentrations below 43.52 µg/g, the correlations between the birth weight and the meconium transferrin and ferritin concentrations were negative (r = -0.61, p < 0.001 and r = -0.43, p = 0.017, respectively). Measurements of transferrin and ferritin in meconium specimens create a new use for these common biomarkers to improve our understanding of the effects of homeostasis in utero on the fetal development and growth. Establishing reference ranges of meconium transferrin and ferritin concentrations and their association with the clinical parameters during pregnancy could aid in the assessment of the impact of intrauterine life on the health status of the neonate and its adaptation to extrauterine life.

The associations between prenatal phthalate exposure measured in child meconium and cognitive functioning of 12-month-old children in two cohorts at elevated risk for adverse neurodevelopment

BACKGROUND

Phthalate metabolites in gestational-maternal urine represents short-term maternal exposure, but meconium, the newborn's first stool may better capture cumulative fetal exposure. We quantified phthalate metabolites in meconium from two cohorts of children at higher risk of adverse neurodevelopment and evaluated associations with their cognitive function at 12 months.

METHODS

Meconium phthalate metabolites were quantified in the Safe Passage Study (SPS), N = 720, a pregnancy cohort with high community-levels of prenatal alcohol use, and the Early Autism Risk Longitudinal Investigation (EARLI), N = 236, a high familial autism risk pregnancy cohort. EARLI also had second and third trimester (T2/T3) maternal urine for exposure assessment. Molar sum of di (2-ethylhexyl) (∑DEHP) metabolites and an anti-androgenic score (AAS) using mono-isobutyl, mono-n-butyl, monobenzyl (MBZP), and DEHP metabolites were computed. Cognitive function was assessed at 12 months using the Mullen Scales of Early Learning-Composite (ELC). Multivariable linear regression assessed associations between loge-transformed metabolites and ELC. Quadratic terms explored nonlinearity and interaction terms of metabolite by child's sex examined effect modification.

RESULTS

In SPS, MBzP (βLinear = -6.73; 95% CI: 12.04, -1.42; βquadratic = 1.95; 0.27, 3.62) and mono (2-ethyl-5-carboxypentyl), (βLinear = -3.81; -7.53, -0.27; βquadratic = 0.93; 0.09, 1.77) had U-shaped associations with ELC. In EARLI, T2 urine mono-carboxyisononyl was associated with linear decrease in ELC, indicating lower cognitive function. Interaction with sex was suggested (P < 0.2) for several urine metabolites, mostly indicating negative association between phthalates and ELC among girls but reversed among boys. Only mono-isononyl phthalate and ∑DEHP had consistent main effect associations across matrixes and cohorts, but similar interaction with sex was observed for meconium-measured ∑DEHP, AAS, MBzP, and mono (2-ethylhexyl) in both cohorts.

CONCLUSIONS

Few phthalate metabolites were consistently associated with children's cognitive function, but a similar set of meconium metabolites from both cohorts displayed sex-specific associations. Gestational phthalate exposure may have sexually-dimorphic associations with early cognitive function in children at higher risk for adverse neurodevelopment.

Ion Chromatography with Pulsed Amperometric Detection for Determining Cyanide in Urine and Meconium Samples

The parents' addictions and eating habits have a significant influence on the child's growth. The first stool of a newborn baby provides a large amount of information about xenobiotics transmitted by the mother's body. The analytical technique used in the study is ion chromatography with pulsed amperometric detection (IC-PAD). The biological samples, which were obtained from women staying in a maternity ward and their partners, revealed cyanide concentrations in urine samples spanning 1.30-25.3 μg L-1. Meanwhile, the results of the meconium samples were in the range of 1.54 μg L-1 to 24.9 μg L-1. Under the optimized chromatographic conditions, the IC-PAD system exhibited satisfactory repeatability (R < 3%, n = 3) and good linearity in the range of 1-100 μg L-1. Thus, it proved to be an effective tool for monitoring trace cyanide concentration in a series of human body fluid matrices, including meconium. Based on the literature review, this is the first application of the IC-PAD analytical technique for the determination of cyanide ions in meconium samples.

Fatty acid ethyl esters in meconium: A biomarker of fetal alcohol exposure and effect

To determine if meconium fatty acid ethyl esters (FAEE) in rat pups is a good biomarker of prenatal exposure and effect to alcohol, three groups of pregnant rats were studied: one control (pair fed) and two treatment groups given 25% alcohol at 2.2 or 5.5 g-1 kg-1 d-1. The pups were delivered on day 20 and, for each dam, were separated into a male and female group. The body, brain, intestines, and placenta of the pups were obtained, weighed, and stored at -20°C. The pups' intestines (as surrogate of meconium) from each group were pooled, and meconium was analyzed by gas chromatography/mass spectroscopy for FAEE. The meconium showed the following FAEE: ethyl palmitate, ethyl stearate, and ethyl linolenate and were only found in the alcohol-treated group and with high specificity but low sensitivity. Mean body weight of the pups was lower in the treatment groups compared to the control groups. Ethyl palmitate concentration correlated negatively to the pups' mean body and brain weights. Therefore, ethyl palmitate, stearate, and linolenate, in meconium of rat pups prenatally exposed to alcohol, are useful biomarkers of prenatal alcohol exposure, with ethyl palmitate a good biomarker of adverse effect on the pups' body and brain weight.

Fatty acid ethyl esters in meconium and substance use in adolescence

Prenatal alcohol exposure (PAE) continues to be a serious public health problem, yet no reliable clinical tools are available for assessing levels of drinking during pregnancy. Fatty acid ethyl esters (FAEEs), the nonoxidative metabolites of ethanol measured in meconium, are potential biomarkers to quantify the level of PAE. The association between the concentrations of FAEEs from meconium and adolescent substance use and related problems was examined in a prospective birth-cohort of adolescents exposed to alcohol and drugs in utero. FAEEs were quantified with gas chromatography via a flame ionization detector. Meconium was analyzed for FAEEs in 216 newborns; 183 of them (81 boys, 102 girls) were assessed at age 15 for alcohol, tobacco, and marijuana use using biologic assays and self-report. Substance use problems were assessed using the Problem Oriented Screening Instrument for Teenagers. Findings from multivariable logistic regression analyses indicated that, after controlling for other prenatal drug exposure and covariates, higher concentrations of FAEEs (ethyl myristate, ethyl palmitate, ethyl oleate, ethyl linoleate, ethyl linolenate, and ethyl arachidonate) were related to a greater likelihood of marijuana use and experiencing substance use problems, but not tobacco or alcohol use, at age 15. Elevated levels of FAEEs in meconium may be promising markers for PAE, identifying newborns at risk for early substance use and developing substance use problems.

Meconium androgens are correlated with ASD-related phenotypic traits in early childhood in a familial enriched risk cohort

BACKGROUND

Prenatal exposure to increased androgens has been suggested as a risk factor for autism spectrum disorder (ASD). This hypothesis has been examined by measurement of steroids in amniotic fluid, cord blood, saliva, and blood with mixed results.

METHODS

To provide an orthogonal measure of fetal exposure, this study used meconium, the first stool of a newborn, to measure prenatal androgen exposure from infants in the Early Autism Risk Longitudinal Investigation (EARLI). EARLI is a familial-enriched risk cohort that enrolled pregnant mothers who already had a child with an ASD diagnosis. In the younger child, we investigated the association between meconium unconjugated (u) and total (t) concentrations of major androgens testosterone (T), dehydroepiandrosterone (DHEA), and androstenedione (A4), and ASD-related traits at 12 and 36 months of age. Traits were measured at 12 months with Autism Observation Scale for Infants (AOSI) and at 36 months with total score on the Social Responsiveness Scale (SRS). One hundred and seventy children had meconium and AOSI, 140 had meconium and SRS, and 137 had meconium and both AOSI and SRS.

RESULTS

Separate robust linear regressions between each of the log-transformed androgens and log-transformed SRS scores revealed three-way interaction between sex of the child, sex of the proband, and testosterone concentration. In the adjusted analyses, t-T, u-A4, and u-DHEA (P ≤ 0.01) were positively associated with AOSI scores, while u-T (P = 0.004) and u-DHEA (P = 0.007) were positively associated with SRS total score among females with female probands (n = 10). Additionally, higher concentrations of u-T (P = 0.01) and t-T (P = 0.01) predicted higher SRS total score in males with male probands (n = 63). Limitations Since we explored three-way interactions, this resulted in a limited sample size for some analyses. This study was from an enriched-risk cohort which may limit generalizability, and this study used ASD-assessment scales as outcomes instead of diagnostic categories. Additionally, the novel use of meconium in this study limits the ability to compare the results in this cohort to others due to the paucity of research on meconium.

CONCLUSIONS

This study supports the utility of meconium for studies of endogenous fetal metabolism and suggests the sex of older siblings with autism should be considered as a biological variable in relevant studies.

Monitoring of prenatal exposure to organic and inorganic contaminants using meconium from an Eastern Canada cohort

Evaluating in utero exposure to inorganic and multiclass organic contaminants is critical to better evaluate potential harmful effects on prenatal and postnatal development. The analysis of meconium, the first bowel discharge of the newborn, has been proposed as a non-invasive way to assess cumulative prenatal exposure. The aim of this study was to implement an analytical method for quantifying 72 targeted organic compounds, including pesticides, pharmaceutical compounds and daily life xenobiotics, in meconium in addition to selected elements (17 elements). We report initial monitoring results based on the analysis of 396 meconium samples from an Eastern Canada cohort (Quebec, Canada). Element contents in meconium were analysed by mass spectrometry after digestion in nitric acid and peroxide. Targeted organic compounds were extracted and purified from meconium samples by a solid-liquid extraction followed by a dispersive-SPE purification before tandem mass spectrometry analysis. Concentrations of targeted elements were within the range of concentration reported in European and US studies but were lower than concentrations found in a developing country cohort (i.e., Pb, Cd). Out of the 72 targeted organic compounds, 31 were detected at least once and 30 were quantified. Compounds with the highest frequency of detection were caffeine, detected in all samples (from 2.80 to 6186 ng g-1), followed by acetaminophen detected in 53% of the samples (up to ~402 µg g-1) and methyl paraben detected in 20% of the samples (up to ~10 µg g-1). Pesticides were detected in low frequencies (< 2%) and low concentration (< 35 ng g-1). Results show that meconium can be used to monitor prenatal exposure of foetus to a wide array of inorganic and organic contaminants.

Preliminary results of identification and quantification of paclitaxel and its metabolites in human meconium from newborns with gestational chemotherapeutic exposure

Objective

Cancer diagnosis during pregnancy occurs in 1 out of 1000 pregnancies with common malignancies including breast and hematological cancers. Fetal exposure to currently utilized agents is poorly described. We directly assessed fetal exposure by screening meconium from 23 newborns whose mothers had undergone treatment for cancer during pregnancy.

Study design

Meconium was collected from newborns whose mothers were diagnosed with cancer during pregnancy and underwent chemotherapy in the second or third trimester as part of the Cancer and Pregnancy Registry. We conducted screening of 23 meconium samples for chemotherapeutics and known metabolites of chemotherapeutics by liquid chromatography-high resolution mass spectrometry (LC-HRMS). Putative identification of paclitaxel and/or its metabolites was made in 8 screened samples. In positively screened samples, we quantified paclitaxel, 3’-p-hydroxypaclitaxel, and 6α-hydroxypaclitaxel by stable isotope dilution-LC-HRMS.

Results

Mean (standard deviation) levels of paclitaxel in positively screened samples were 399.9 (248.6) pg/mg in meconium samples from newborn born to mothers that underwent chemotherapy during pregnancy. 3’-p-hydroxypaclitaxel and 6α-hydroxypaclitaxel mean levels were 105.2 (54.6) and 113.4 (48.9) pg/mg meconium, respectively.

Conclusion

Intact paclitaxel, 3’-p-hydroxypaclitaxel, and 6α-hydroxypaclitaxel were detected in meconium, providing unambiguous confirmation of human fetal exposure. Variability in meconium levels between individuals may indicate a potential for reducing fetal exposure based on timing, dosing, and individual characteristics. This preliminary study may provide an approach for examining the effects of cancer diagnosis during pregnancy on other outcomes by providing a measure of direct fetal exposure.

Association of Fatty Acid Ethyl Esters in Meconium of Neonates with Growth Deficits at Birth: a Prospective, Single-Centre Cohort Study

BACKGROUND

In this prospective cohort study, we investigated the association between fatty acid ethyl esters (FAEEs) in meconium as biomarkers of prenatal ethanol exposure and growth deficits, as birth outcomes, that constitute several of the key cardinal features of fetal alcohol syndrome.

METHODS

A total of 157 meconium samples were collected from enrolled infants within 24 hours of birth, and nine FAEEs were quantified using liquid chromatography/tandem mass spectrometry. The relationships between cumulative concentrations of nine species of FAEEs in meconium and birth parameters of growth (age-sex-specific centiles of head circumference [HC], weight, and length) and respective and combined birth outcomes of growth deficits (HC ≤ 10th centile, weight ≤ 10th centile, and length ≤ 10th centile) were determined.

RESULTS

Multivariate logistic regression analysis demonstrated that higher cumulative concentrations of meconium FAEEs correlated with elevated risks for HC and length, both, 10th percentile or less (adjusted odds ratio [aOR], 2.94; 95% confidence interval [CI], 1.12-7.74; P = 0.029) and HC and weight and length, all of them, 10th percentile or less (aOR, 3.27; 95% CI, 1.12-9.59; P = 0.031).

CONCLUSION

The elevated cumulative FAEEs in meconium were associated with combined growth deficits at birth, specifically HC and length, both, 10th percentile or less, which might be correlated with detrimental alcohol effects on fetal brain and bone development, suggesting a plausible alcohol-specific pattern of intrauterine growth restriction.

Associations of birth mode with cord blood cytokines, white blood cells, and newborn intestinal bifidobacteria

The associations of Cesarean delivery with offspring metabolic and immune-mediated diseases are believed to derive from lack of mother-to-newborn transmission of specific microbes at birth. Bifidobacterium spp., in particular, has been hypothesized to play a health-promoting role, yet little is known about how delivery mode modifies colonization of the newborn by this group of microbes. The aim of this research was to examine the presence of Bifidobacterium in meconium and in the transitional stool, and to assess cytokine levels and hematological parameters in the venous cord blood of infants born by elective, pre-labor Cesarean section vs. vaginal delivery in Southern Brazil. We recruited 89 mother-newborn pairs (23 vaginal delivery and 66 elective cesarean delivery), obtained demographic information from a structured questionnaire and clinical information from medical records. We obtained umbilical cord venous blood and meconium samples following delivery and the transitional stool (the first defecation after meconium) before discharge. We determined plasma levels of IL-1β, IL-10, IL-6, GM-CSF, IL-5, IFN-γ, TNF-α, IL-2, IL-4 and IL-8 in the cord blood, and presence of stool Bifidobacterium by real time PCR. Compared to vaginally-delivered neonates, Cesarean-delivered neonates had a lower leukocyte count (p = 0.037), lower hemoglobin (p = 0.04), and lower levels of the cytokine GM-CSF (p = 0.009) in the cord blood. Moreover, Bifidobacterium was detected less often in the transitional stool of Cesarean-delivered neonates compared to vaginally-delivered neonates (p = 0.001). The results indicate that pre-labor Cesarean birth may be associated with microbial and hematological alterations in the neonate. The clinical significance of these findings remains to be determined in larger prospective birth cohort studies.

The evidential statistical paradigm in genetics

Concerns over reproducibility in research has reinvigorated the discourse on P-values as measures of statistical evidence. In a position statement by the American Statistical Association board of directors, they warn of P-value misuse and refer to the availability of alternatives. Despite the common practice of comparing P-values across different hypothesis tests in genetics, it is well-appreciated that P-values must be interpreted alongside the sample size and experimental design used for their computation. Here, we discuss the evidential statistical paradigm (EP), an alternative to Bayesian and Frequentist paradigms, that has been implemented in human genetics studies. Using applications in Cystic Fibrosis genetic association analyses, and describing recent theoretical developments, we review how to measure statistical evidence using the EP in the presence of covariates, model misspecification, and for composite hypotheses. Novel graphical displays are presented, and software for their computation is highlighted. The implications of multiple hypothesis testing for the EP are delineated in the analyses, demonstrating a view more consistent with scientific reasoning; the EP provides a theoretical justification for replication that is a requirement in genetic association studies. As genetic studies grow in size and complexity, a fresh look at measures of statistical evidence that are sensible amid the analysis of big data are required.

Inhibition and counterinhibition of Surfacen, a clinical lung surfactant of natural origin

Inactivation of pulmonary surfactant by different components such as serum, cholesterol or meconium contributes to severe respiratory pathologies through destabilization and collapse of airspaces. Recent studies have analyzed in detail how the interfacial properties of natural surfactant purified from animal lungs are altered as a consequence of its exposure to serum proteins or meconium-mobilized cholesterol. It has been also demonstrated that pre-exposure of surfactant to polymers such as hyaluronic acid provides resistance to inactivation by multiple inhibitory agents. In the current work, we have extended these studies to the analysis of Surfacen, a clinical surfactant currently in use to rescue premature babies suffering or at risk of respiratory distress due to congenital lack of surfactant. This surfactant is also strongly inhibited by both meconium and serum when tested in the captive bubble surfactometer (CBS) under conditions mimicking respiratory dynamics. As it occurs with native surfactant, Surfacen is markedly protected from inhibition by pre-exposure to hyaluronic acid, confirming that clinical surfactants can be improved to treat pathologies associated with strongly deactivating contexts, such as those associated with lung injury and inflammation. Remarkably, we found that, under physiologically-mimicking conditions, a cholesterol-free clinical surfactant such as Surfacen is less susceptible to inhibition by cholesterol-mobilizing environments than cholesterol-containing natural surfactant, as a consequence of a markedly reduced susceptibility to incorporation of exogenous cholesterol.

Determining the pattern and prevalence of alcohol consumption in pregnancy by measuring biomarkers in meconium

OBJECTIVE

To investigate the feasibility of determining the pattern and prevalence of alcohol consumption in pregnancy by measuring ethanol biomarkers in meconium.

DESIGN

Population-based observational study.

SETTING

Inner-city maternity unit in Scotland, UK.

POPULATION

Random sample of singleton infants delivered after 36 completed weeks' gestation.

METHODS

Fatty acid ethyl esters (FAEEs) and ethyl glucuronide (EtG) in meconium were measured by liquid chromatography-mass spectroscopy. Samples were frozen at -20°C before analysis. Results were compared anonymously with demographic data including maternal age, parity, smoking, ethnicity and postcode and with infant gestation, birth weight and head circumference. Written informed consent was obtained from all subjects.

RESULTS

235 samples of meconium were analysed (70% of eligible babies). Only four (1%) of mothers declined to participate. FAAEs were detected in all, including four samples below the limit of quantification (10 ng/g). 98 (42%) samples had FAEE concentrations >600 ng/g. EtG was detectable in 93 (40%) samples; in 35 (15%) EtG concentration was >30 ng/g. No mother reported heavy alcohol consumption in pregnancy. FAAE concentration correlated with EtG (Pearson's coefficient; p<0.001). There was no association between either biomarker and maternal age, parity, smoking, ethnicity or postcode, or infant gestation, birth weight or head circumference.

CONCLUSION

Measurement of ethanol biomarkers in meconium is a feasible tool for determining the pattern and prevalence of alcohol consumption in pregnancy. Data suggest that at least 15% of pregnant women in the west of Scotland are consuming significant quantities of alcohol during latter pregnancy.

Intrapartum factors associated with neonatal hypoxic ischemic encephalopathy: a case-controlled study

BACKGROUND

Neonatal encephalopathy (NE) affects 2-4/1000 live births with outcomes ranging from negligible neurological deficits to severe neuromuscular dysfunction, cerebral palsy and death. Hypoxic ischemic encephalopathy (HIE) is the sub cohort of NE that appears to be driven by intrapartum events. Our objective was to identify antepartum and intrapartum factors associated with the development of neonatal HIE.

METHODS

Hospital databases were searched using relevant diagnosis codes to identify infants with neonatal encephalopathy. Cases were infants with encephalopathy and evidence of intrapartum hypoxia. For each hypoxic ischemic encephalopathy case, four controls were randomly selected from all deliveries that occurred within 6 months of the case.

RESULTS

Twenty-six cases met criteria for hypoxic ischemic encephalopathy between 2002 and 2014. In multivariate analysis, meconium-stained amniotic fluid (aOR 12.4, 95% CI 2.1-144.8, p = 0.002), prolonged second stage of labor (aOR 9.5, 95% CI 1.0-135.3, p = 0.042), and the occurrence of a sentinel or acute event (aOR 74.9, 95% CI 11.9-infinity, p < 0.001) were significantly associated with hypoxic ischemic encephalopathy. The presence of a category 3 fetal heart rate tracing in any of the four 15-min segments during the hour prior to delivery (28.0% versus 4.0%, p = 0.002) was more common among hypoxic ischemic encephalopathy cases.

CONCLUSION

Prolonged second stage of labor and the presence of meconium-stained amniotic fluid are risk factors for the development of HIE. Close scrutiny should be paid to labors that develop these features especially in the presence of an abnormal fetal heart tracing. Acute events also account for a substantial number of HIE cases and health systems should develop programs that can optimize the response to these emergencies.

Correlations between ceruloplasmin, lactoferrin and myeloperoxidase in meconium

BACKGROUND AND AIMS

Oxidative stress and the generation of reactive oxygen/nitrogen species has a known significant impact on intrauterine fetal growth and the risk of metabolic diseases in adulthood. Compounds accumulated in fetal meconium may be a source of information about the oxidoreductive status during the intrauterine development. Three metal-containing proteins ceruloplasmin (CP), lactoferrin (LF) and myeloperoxidase (MPO) constitute the complementary panel modulating oxidative stress. The aim of this study was to assess the concentrations of these proteins and their correlations in meconium from healthy neonates.

METHODS

The CP, LF and MPO concentrations were determined using ELISA Kits. All serial meconium portions (n=80) were collected from healthy full-term neonates (n=19).

RESULTS

The mean±SD concentrations [μg/g] in meconium samples were as follows: CP 312.4±229.7 (range 52.2-1076), LF 45.6±78.9 (range 1.7-511.4), MPO 1.8±1.7 (range 0.02-8.8) with statistically significant correlations between CP vs. LF (R=0.459, p=0.00009) and LF vs. MPO (R=0.354, p=0.0013). A statistically significant increase in the concentrations (p<0.05) between the first and the last meconium portions was found for LF (p=0.027) and for MPO (p=0.0006).

CONCLUSIONS

Strong correlations between the meconium concentrations of CP, LF and MPO indicate a possible role of these complementary proteins in maintaining homeostasis of the intrauterine environment of the fetus. CP, LF and MPO measured in meconium may serve as biomarkers for assessment of impairment of oxidative balance during intrauterine life with its potential impact on disease development in adulthood.

Assessment of tobacco, alcohol and cannabinoid metabolites in 645 meconium samples of newborns compared to maternal self-reports

Prenatal psychoactive substance exposure has significant impact on neonatal health and child development and the development of reliable biomarkers is critical. Meconium presents several advantages for detecting prenatal exposure to psychoactive substances, as it is easy to collect and provides a broad time frame of exposure (third trimester). The aim of our study was to compare the prevalence of alcohol, tobacco and/or cannabis use during the third trimester of pregnancy (using maternal self-reports) with the results of meconium testing of their metabolites in newborns (cotinine, ethyl-glucuronide (EtG) and cannabinoid metabolites). Among all deliveries (993) that occurred in all maternities in Rouen (Normandy) during a defined time period (5 consecutive weeks in August, 2010 and August, 2011), 724 mothers were included and 645 meconium samples were collected. Maternal self-reports, using the Addiction Severity Index (5th edition), and meconium samples were collected within 72 h of delivery. Cotinine detection appears highly correlated to maternal self-reports (Kappa value: 0.79; [95%CI: 0.73-0.85]). Moreover, detection in meconium seems more accurate in the prediction of neonatal consequences of prenatal tobacco exposure as compared to maternal self-reports. In contrast, we have found a lower concordance between maternal self-reports and meconium testing for EtG and cannabinoid metabolites (Kappa value: 0.13; [95%CI: 0.04-0.22] and: 0.30; [95%CI: -0.03-0.63], respectively); however the total number of EtG- and cannabinoid-positive meconium samples was small. Interestingly, meconium samples with the highest levels of EtG mainly corresponded to negative maternal self-reports. Fetal exposure to alcohol, tobacco or cannabis may also considerably differ as displayed in our pairs of dizygotic twins. Finally, a polyconsumption of these psychoactive substances was not frequently observed according to meconium testing. In conclusion, cotinine detection appears as a valuable meconium biomarker. EtG measurement in meconium samples seems interesting if there is any risk of high fetal exposure, whereas assessment of prenatal cannabis exposure, using meconium testing, needs to be improved.

Effects of surfactant/budesonide therapy on oxidative modifications in the lung in experimental meconium-induced lung injury

Meconium aspiration syndrome (MAS) is a serious condition, which can be treated with exogenous surfactant and mechanical ventilation. However, meconium-induced inflammation, lung edema and oxidative damage may inactivate delivered surfactant and thereby reduce effectiveness of the therapy. As we presumed that addition of anti-inflammatory agent into the surfactant may alleviate inflammation and enhance efficiency of the therapy, this study was performed to evaluate effects of surfactant therapy enriched with budesonide versus surfactant-only therapy on markers of oxidative stress in experimental model of MAS. Meconium suspension (25 mg/ml, 4 ml/kg) was instilled into the trachea of young rabbits, whereas one group of animals received saline instead of meconium (C group, n = 6). In meconium-instilled animals, respiratory failure developed within 30 min. Then, meconium-instilled animals were divided into 3 groups according to therapy (n = 6 each): with surfactant therapy (M + S group), with surfactant + budesonide therapy (M + S + B), and without therapy (M group). Surfactant therapy consisted of two bronchoalveolar lavages (BAL) with diluted surfactant (Curosurf, 5 mg phospholipids/ml, 10 ml/kg) followed by undiluted surfactant (100 mg phospholipids/kg), which was in M + S + B group enriched with budesonide (Pulmicort, 0.5 mg/ml). Animals were oxygen-ventilated for additional 5 hours. At the end of experiment, blood sample was taken for differential white blood cell (WBC) count. After euthanizing animals, left lung was saline-lavaged and cell differential in BAL was determined. Oxidative damage, i.e. oxidation of lipids (thiobarbituric acid reactive substance (TBARS) and conjugated dienes) and proteins (dityrosine and lysine-lipoperoxidation products) was estimated in lung homogenate and isolated mitochondria. Total antioxidant capacity was evaluated in lung homogenate and plasma. Meconium instillation increased transmigration of neutrophils and production of free radicals compared to controls (P < 0.05). Surfactant therapy, but particularly combined surfactant + budesonide therapy reduced markers of oxidative stress versus untreated animals (P < 0.05). In conclusion, budesonide added into surfactant enhanced effect of therapy on oxidative damage of the lung.

[Meconium evacuation to improve feeding tolerance in very low birth weight preterm infants (Emita Protocol)]

INTRODUCTION

It has been reported that feeding tolerance in preterm infants is associated with an early passage of meconium. Prospective, randomized or historical control studies that stimulate meconium evacuation have reported varied results. This study was intented to evaluate the use of enemas to speed up meconium evacuation, facilitating feeding tolerance.

PATIENTS AND METHOD

A controlled multicenter randomized trial that evaluated the use of physiological saline enemas with glycerol (0.8 ml glycerol + 3 ml saline or 1 ml glycerol + 5 ml saline depending on babies weighing less or more than 800 g at birth, respectively) versus simulation. This procedure was performed in the first 96 hours of life in infants with birth weight between 500 and 1,250 g. Maternal (preterm delivery, clinical chorioamnionitis, gestational hypertension, administration of magnesium sulfate and prenatal corticosteroids, fetal Doppler altered, type of delivery, gender, weight and gestational age, assessment of Apgar and need for assisted ventilation and oxygenotherapy) and nutritional history (age when feeding volumes of 100 ml/kg/day and full enteral feeding were reached, age to remove meconium, number of days on parenteral nutrition, weight at 28 days, weekly volumes of breast milk and preterm formula) were described.

RESULTS

No significant differences were obtained regarding the age to reach full enteral intake or 100 ml/kg/day were found among the 101 patients in the study. Also, no differences in the following secondary variables are observed: number of episodes of late sepsis with or without positive blood culture, hyperbilirubinemia, necrotizing enterocolitis and intraventricular hemorrhage.

CONCLUSIONS

The routine use of saline enemas and glycerin in this study does not alter the enteral feeding tolerance in very low birth weight preterm infants.

Biochemical Screening for in utero Drug Exposure

Licit and illicit drug use is a common complication of pregnancy. Accurate information on drug use is difficult to obtain for many reasons as women fear self-disclosure or consenting for drug testing due to stigma, guilt, and fear of social and legal harm. As information about drug use is clinically very important, biochemical testing is an important adjunct to careful maternal history. In addition, research studies depend on accurate measures of exposure when reporting risks of a substance. This paper delineates available matrices for and methods of biochemical drug testing in pregnant women and neonates.

Use of meconium in perinatal epidemiology: potential benefits and pitfalls

PURPOSE

Meconium is a biomarker matrix that can be used to assess cumulative exposures in epidemiologic studies of prenatal risk factors. Depending on when meconium is collected, different exposure windows during pregnancy can be measured. However, little guidance exists regarding the extent to which timing of meconium collection will influence resulting effect estimates.

METHODS

We performed a simulation study of prenatal tobacco smoke exposure (assessed from meconium nicotine) and birth weight. We discuss four typical meconium collection methods capturing different exposure windows and assess the biases induced by these methods.

RESULTS

In simulations assuming that exposure to tobacco smoke only during late gestation was of etiologic relevance to birth weight, use of a meconium collection method that captured exposure windows other than late gestation resulted in biased estimates of the true nicotine-birth weight association.

CONCLUSIONS

Using meconium collection methods that do not reflect an exposure window of etiologic relevance can lead to biased results and erroneous conclusions regarding the nature of prenatal exposure-outcome associations. Understanding how prenatal exposure patterns vary across the pregnancy and exposure windows of etiologic relevance is essential in determining when and how to collect meconium for use in biomarker studies of prenatal exposure.

Rates of fetal polydrug exposures in methadone-maintained pregnancies from a high-risk population

Methadone maintenance treatment (MMT) is the standard of care during pregnancy for opioid-dependency, showing efficacy in improving prenatal care and reducing risk of relapse. By design, however, MMT is only intended to prevent withdrawal thus facilitating cognitive behavioural interventions. In order to maximize the benefits of MMT, it is essential that methadone is both properly prescribed and that additional addiction treatment is concurrently administered. This study aims to determine the effectiveness of MMT engagement in high-risk pregnant women in reducing polydrug use by objective laboratory examination of neonatal meconium.

Meconium fatty acid ethyl esters as biomarkers of late gestational ethanol exposure and indicator of ethanol-induced multi-organ injury in fetal sheep

BACKGROUND

Meconium fatty acid ethyl esters (FAEE) constitute a biomarker of heavy fetal ethanol exposure. Our objective was to measure meconium FAEE in fetal sheep following daily, relatively moderate-dose ethanol exposure in late gestation, and to evaluate their utility in identifying fetal organ-system injury.

METHODS

Pregnant ewes received ethanol (0.75 g/kg; n = 14) or saline (n = 8) via 1-h i.v. infusion daily during the third trimester equivalent, while additional pregnant sheep served as untreated controls (n = 6). The daily ethanol regimen produced similar maximal maternal and fetal plasma ethanol concentrations of 0.11-0.12 g/dL. Ewes and fetuses were euthanized shortly before term, and meconium was collected and analyzed for FAEE (ethyl palmitate, stearate, linoleate, and oleate).

RESULTS

Meconium total FAEE concentration was significantly higher in ethanol-exposed fetuses compared with controls, and a positive cut-off of 0.0285 nmol total FAEE/g meconium had 93.3% sensitivity and specificity for detecting fetal ethanol exposure. When the studied animals (ethanol-exposed and controls) were classified according to meconium FAEE concentration, FAEE-positive and FAEE-negative groups frequently differed with respect to previously examined pathological endpoints, including nephron endowment, lung collagen deposition, cardiomyocyte maturation, and tropoelastin gene expression in cerebral vessels. Furthermore, in all studied animals as a group (ethanol-exposed and controls combined), meconium FAEE concentration was correlated with many of these pathological endpoints in fetal organs.

CONCLUSIONS

We conclude that, in fetal sheep, meconium FAEE could serve as a biomarker of daily ethanol exposure in late gestation and could identify fetuses with subtle ethanol-induced toxic effects in various organs. This study illustrates the potential for using meconium FAEE to identify neonates at risk for dysfunction of major organs following in-utero ethanol exposure that does not result in overt physical signs of ethanol teratogenicity.

Assessment of prenatal exposure to arsenic in Tenerife Island

INTRODUCTION

Increasing awareness of the potential chronic health effects of arsenic (As) at low exposure levels has motivated efforts to better understand impaired child development during pregnancy by biomarkers of exposure. The aims of this study were to evaluate the prenatal exposure to As by analysis of an alternative matrix (meconium), to examine its effects on neonatal outcomes and investigate the association with maternal lifestyle and dietary habits during pregnancy.

METHODS

A transversal descriptive study was conducted in Tenerife (Spain). A total of 96 mother-child pairs participated in the study. A questionnaire on sociodemographic, lifestyle and dietary habits during pregnancy was administered the day after the delivery. Analysis of total As in meconium was performed by inductively coupled plasma-optical emission spectrometer.

RESULTS

Total As was detected in 37 (38.5%) meconium samples. The univariate logistic regression model indicates that prenatal exposure to As was associated with a low intake of eggs per week (OR 0.56; CI (95%): 0.34-0.94) during pregnancy. Conversely, frequent intake of vegetables was associated with prenatal As exposure (OR: 1.19; CI (95%): 1.01-1.41) and frequent intake of processed meat (as bacon, Frankfurt's sausage, and hamburger) shows a trend to As prenatal exposure (OR: 8.54; CI (95%): 0.80-90.89). The adjusted multivariate logistic regression model indicates that only frequent intake of vegetables maintains the association (OR: 1.31; CI (95%): 1.02-1.68).

CONCLUSION

The studied population presented a low As exposure and was not associated with neonatal effects. Maternal consumption of vegetables during pregnancy was associated with detectable meconium As levels; however the concentration detected in meconium was too low to be considered a major public health concern in this geographical area.

Selective phosphodiesterase 3 inhibitor olprinone attenuates meconium-induced oxidative lung injury

Since inflammation and oxidation play a key role in the pathophysiology of neonatal meconium aspiration syndrome, various anti-inflammatory drugs have been tested in the treatment. This study evaluated whether the phosphodiesterase (PDE) 3 inhibitor olprinone can alleviate meconium-induced inflammation and oxidative lung injury. Oxygen-ventilated rabbits intratracheally received 4 ml/kg of meconium (25 mg/ml) or saline. Thirty minutes after meconium/saline instillation, meconium-instilled animals were treated by intravenous olprinone (0.2 mg/kg) or were left without treatment. All animals were oxygen-ventilated for an additional 5 h. A bronchoalveolar lavage (BAL) of the left lungs was performed and differential leukocyte count in the sediment was estimated. The right lungs were used to determine lung edema by wet/dry weight ratio, as well as to detect oxidative damage to the lungs. In the lung tissue homogenate, total antioxidant status (TAS) was determined. In isolated lung mitochondria, the thiol group content, conjugated dienes, thiobarbituric acid-reactive substances (TBARS), dityrosine, lysine-lipid peroxidation products, and activity of cytochrome c oxidase (COX) were estimated. To evaluate the effects of meconium instillation and olprinone treatment on the systemic level, TBARS and TAS were determined in the blood plasma, as well. Meconium instillation increased the relative numbers of neutrophils and eosinophils in the BAL fluid, increased edema formation and concentrations of oxidation markers, and decreased TAS. Treatment with olprinone reduced the numbers of polymorphonuclears in the BAL fluid, decreased the formation of most oxidation markers in the lungs, reduced lung edema and prevented a decrease in TAS in the lung homogenate compared to non-treated animals. In the blood plasma, olprinone decreased TBARS and increased TAS compared to the non-treated group. Conclusion, the selective PDE3 inhibitor olprinone has shown potent antioxidative and anti-inflammatory effects in the meconium-induced oxidative lung injury.

Clinical use of meconium fatty acid ethyl esters for identifying children at risk for alcohol-related disabilities: the first reported case

Fatty acid ethyl esters (FAEEs) in meconium are validated biomarkers of heavy fetal alcohol exposure that may potentially be used clinically for identifying children at risk for alcohol-related disabilities. However, until now, FAEEs have been largely used anonymously in epidemiological studies, and by child protection authorities in need for verification of heavy alcohol use in pregnancy. Here we describe the first case of a neonate identified as part of a research study on a pilot neonatal screening program for prenatal alcohol exposure. The neonate's meconium tested high for FAEEs (52 nmol/g; positive cut-off ≥ 2 nmol/g), which prompted active follow-up of the infant's development, identifying early neurocognitive problems and allowing initiation of a remedial program.

Meconium impairs pulmonary surfactant by a combined action of cholesterol and bile acids

Mechanisms for meconium-induced inactivation of pulmonary surfactant as part of the meconium aspiration syndrome in newborn infants, to our knowledge, are not clearly understood. Here we have studied the biophysical mechanisms of how meconium affects surface activity of pulmonary surfactant and whether the membrane-perturbing effects of meconium can be mimicked by exposure of surfactant to a mixture of bile acids and cholesterol. Surface activity of pulmonary surfactant complexes purified from animal lungs was analyzed in the absence and in the presence of meconium in standard surface balances and in a captive bubble surfactometer. We have also evaluated accumulation of surfactant at the air-liquid interface by what we believe to be a novel microtiter plate fluorescent assay, and the effect of meconium components on surfactant membrane fluidity using Laurdan fluorescence thermotropic profiles and differential scanning calorimetry thermograms. Rapid interfacial adsorption, low surface tension upon film compression, efficient film replenishment upon expansion, and thermotropic properties of surfactant complexes are all adversely affected by meconium, and, in a similar manner, they are affected by cholesterol/taurocholate mixtures but not by taurocholate alone. We conclude that inhibition of surfactant by meconium can be mimicked by a bile salt-promoted incorporation of excess cholesterol into surfactant complexes. These results highlight the potential pathogenic role of cholesterol-mobilizing agents as a crucial factor resulting in cholesterol induced alterations of structure and dynamics of surfactant membranes and films.

Perinatal lead and mercury exposure in Austria

OBJECTIVE

The heavy metals lead (Pb) and mercury (Hg) are ubiquitous environmental pollutants with high neurotoxic potential. We aimed to compare perinatal Pb and Hg concentrations and to explore the potential association between Pb and Hg exposure and newborn anthropometry.

STUDY DESIGN

Pregnant women were recruited in 2005 at the General Hospital Vienna for participation in this longitudinal study. Pb and Hg concentrations were measured in maternal blood and hair, placenta, cord blood, meconium, and breast milk of 53 mother-child pairs by CV-AAS, GF-AAS, and HPLC-CV-ICPMS. We conducted bivariate analyses and categorical regression analysis (CATREG) to evaluate the determinants of Pb and Hg exposure, and of infant anthropometry.

RESULTS

Median Pb and total Hg contents were low, i.e., 25 μg/L (maternal blood-Pb), 13 μg/L (cord blood-Pb), 0.7 μg/L (maternal blood-Hg), and 1.1 μg/L (cord blood-Hg). Hg levels in maternal and fetal tissues were frequently correlated (r>0.3, P<0.05, respectively). Regarding Pb, only maternal blood and cord blood concentrations correlated (P=0.043). Cord blood levels indicated higher Hg exposure but lower Pb exposure relative to maternal blood contents. Adjusted CATREG models indicated the significant predictors of birth length (placenta-Pb, gestational length, meconium-Pb), birth weight (placenta-Pb, gestational length, maternal blood-Pb), and head circumference (maternal education, maternal height). Besides one significant correlation between maternal hair Hg and birth length, the mercury levels were not associated with newborn anthropometry.

CONCLUSIONS

Our data implicate that different modes of action may exist for placentar transfer of Pb and Hg as well as that low Pb exposure levels can result in lower birth weight. The findings related to newborn anthropometry need to be confirmed by the examination of larger study groups. Further research is needed to clarify the mechanisms of Pb and Hg transfer via the placenta, and to explore how prenatal Pb exposure is related to intrauterine growth.

Magnetic resonance imaging in the prenatal diagnosis of congenital diarrhea

OBJECTIVE

Congenital diarrhea is very rare, and postnatal diagnosis is often made once the condition has caused potentially lethal fluid loss and electrolyte disorders. Prenatal detection is important to improve the immediate neonatal prognosis. We aimed to describe the prenatal ultrasound and magnetic resonance (MRI) imaging findings in fetuses with congenital diarrhea.

METHODS

The study reports the pre- and postnatal findings in four fetuses that presented with generalized bowel dilatation and polyhydramnios. We analyzed the fetal ultrasound and MRI examinations jointly, then compared our provisional diagnosis with the amniotic fluid biochemistry and subsequently with the neonatal stool characteristics.

RESULTS

In each of the four cases an ultrasound examination between 22 and 30 weeks' gestation showed moderate generalized bowel dilatation and polyhydramnios suggesting intestinal obstruction. MRI examinations performed between 24 and 32 weeks' gestation confirmed that the dilatation was of gastrointestinal (GI) origin, with a signal indicating intraluminal water visible throughout the small bowel and colon. The expected hypersignal on T1-weighted sequences characteristic of physiological meconium was absent in the colon and rectum. This suggested that the meconium had been completely diluted and flushed out by the water content of the bowel. The constellation of MRI findings enabled a prenatal diagnosis of congenital diarrhea. The perinatal lab test findings revealed two cases of chloride diarrhea and two of sodium diarrhea.

CONCLUSION

Congenital diarrhea may be misdiagnosed as intestinal obstruction on prenatal ultrasound but has characteristic findings on prenatal MRI enabling accurate diagnosis; this is important for optimal neonatal management.

A liquid chromatography tandem mass spectrometry method for the simultaneous quantification of 20 drugs of abuse and metabolites in human meconium

A method for the simultaneous quantification of 20 cocaine, amphetamine, opiate, and nicotine analytes in meconium, the first neonatal feces, by liquid chromatography tandem mass spectrometry was developed and validated. Specimen preparation included methanol homogenization and solid phase extraction. Two injections were required to achieve sufficient sensitivity and linear dynamic range. Linearity ranged from 0.5-25 up to 500 ng/g (250 ng/g p-hydroxymethamphetamine), and correlation coefficients were >0.996. Imprecision was <10.0% CV, analytical recovery 85.5-123.1%, and extraction efficiencies >46.7% at three concentrations across the linear range. Despite significant matrix effects of -305.7-40.7%, effects were similar for native and deuterated analytes. No carryover, endogenous or exogenous interferences were observed, with analyte stability at room temperature, 4 degrees C, and -20 degrees C and on the autosampler >70%, except for 6-acetylmorphine, hydrocodone, oxycodone, and morphine. Method applicability was demonstrated by analyzing meconium from drug-exposed neonates.

Elevated fatty acid ethyl esters in meconium of sheep fetuses exposed in utero to ethanol--a new animal model

Specific fatty acid ethyl esters (FAEE) in meconium of newborns have been shown to correlate with maternal ethanol exposure. An animal model is needed to assess the validity of this biomarker. We hypothesized that the pregnant/fetal sheep is a feasible animal model for validating FAEE as a biomarker of prenatal ethanol exposure. Nine pregnant ewes were treated during the third trimester with different i.v. ethanol doses. The control group consisted of 14 pregnant ewes exposed to similar volumes of saline. On gestational d 133, the fetuses were delivered and meconium samples removed. FAEEs were quantified by gas chromatography-flame ionization detection. FAEEs were found in both control and ethanol exposed fetuses. Ethyl oleate, ethyl linoleate, and ethyl arachidonate levels were significantly higher in the ethanol-exposed sheep. Ethyl oleate was the FAEE that correlated most strongly with alcohol ingestion during pregnancy and had the greatest area under the curve (0.94). Using a cut-off value of 131 ng/g ethyl oleate dry weight, sensitivity was 89% and specificity was 100%. In conclusion, pregnant ewes are a feasible model for validating biomarkers of prenatal ethanol exposure. Ethyl oleate, ethyl linoleate, and ethyl arachidonate may be useful biomarkers of prenatal alcohol exposure.

Idiopathic slow transit constipation is rare. But delayed passage of meconium is common in the constipation clinic

We hypothesise that constipated children would be more likely to come from a socially deprived background. We also hypothesise that a percentage of children with resistant constipation would have a congenital gut motility problem that might be recognised at birth, and that some of these would have slow transit constipation that could be recognised on nuclear transit study. One hundred and forty children with a constipation related diagnosis were seen in the last 4 years, and were reviewed as a retrospective audit. Twenty-six children who were felt likely to have a congenital cause for their constipation were offered nuclear colon transit study to search for slow transit constipation. One hundred and forty children from the constipation clinic were reviewed. There were 67 females (47.9%) and 73 males (52.1%), a sex ratio near equality. The mean age at presentation was 5.38 years. Forty-one percent were formally discharged, 36% were lost to follow up, and 23% are still being seen. There was a highly significant tendency for these children to have delayed passage of meconium, as compared normal newborns (P << 0.001). Twenty-six children were considered for possible transit study, and 14 were performed. Four of these were normal, seven showed hold up in the recto-sigmoid, and three showed more proximal slow transit. Two of these probably have non ISTC diagnoses. Social class seems similar to the general population on the criterion employed. Delayed passage of meconium in this group was significantly more frequent than in the general population, but only one of the group seems likely to have truly idiopathic slow transit constipation, and he did not have delayed passage of meconium. There is no evidence for an effect of social class in this population. Idiopathic slow transit constipation itself is rare.

Effects of meconium on airway reactivity to histamine and acetylcholine in vitro

To better understand the mechanisms contributing to altered airway reactivity in the meconium aspiration syndrome, in this study we investigated whether there could be a meconium dose-dependent response of tracheal smooth muscle and lung tissue reactivity to histamine and acetylcholine in vitro. Tracheal and lung tissue strips from healthy guinea pigs were incubated for 1 hour in organ chambers with three different concentrations of meconium (1, 2, and 5 mg/ml) or in Krebs-Henseleit solution. Thereafter, the contractile responses to histamine and acetylcholine were recorded. Cumulative doses of histamine and acetylcholine increased reactivity of the strips in all groups. Tracheal smooth muscle reactivity to histamine and acetylcholine (10(-5)-10(-3) mol/l) was highest with the highest meconium concentration. In contrast, lung tissue reactivity tended to decrease with increasing meconium concentration. The mechanisms influencing the airway smooth muscle contractile response to meconium require further studies.

Assessment of prenatal tobacco smoke exposure by determining nicotine and its metabolites in meconium

Meconium samples collected from 115 neonates were analysed for nicotine, cotinine and trans -3-hydroxycotinine (OH-cotinine) by means of high-performance liquid chromatography (HPLC) to identify prenatal smoke exposure. The self-reported maternal smoking status during pregnancy was determined by means of a questionnaire and verified by measurements in urine prior to childbirth. The total sum of nicotine and its metabolites (Sum(tot)) of the first passed meconium samples was 1560 +/- 1024 pmol/g in newborns of smoking mothers. Smoking of less than five cigarettes was clearly detected. Sum(tot) remained constant in all meconium samples passed by a neonate in succession. However, the proportion of nicotine decreased with the time of passage after birth and the OH-cotinine proportion increased, whereas cotinine hardly changed. Nicotine or its metabolites were not detectable in meconium (detection limit < 20 pmol/g), when the mothers were only exposed to environmental tobacco smoke (ETS) using the HPLC method. The hypothesis that the content of nicotine metabolites in meconium reflects long-term smoke exposure could not be confirmed in newborns whose mothers had quit smoking during the latter half of pregnancy. Determining Sum(tot) enables the intensity of continuous smoking during pregnancy to be estimated in all meconium samples passed by a newborn.

Obstetric cholestasis in Hong Kong--local experience with eight consecutive cases

Obstetric cholestasis is associated with maternal morbidity and adverse foetal outcomes. No information on local incidence is available. We present our experience with eight consecutive cases of obstetric cholestasis diagnosed between January 2003 and December 2005 in a regional hospital in Hong Kong. Three patients presented with pruritus without rash, three with impaired liver function, and two with elevated blood pressure postpartum. Meconium-stained liquor was present in five patients and four had spontaneous preterm delivery (between 34 and 36 weeks). The higher the bile acid level, the more marked the prematurity (correlation coefficient, -0.771; P=0.025). All those presenting with itchiness delivered preterm. Two patients developed pre-eclampsia. The rates of labour induction and abdominal delivery were both 38%. Heightened awareness among clinicians is required to recognise patients with obstetric cholestasis. Affected pregnancies are associated with meconium passage and prematurity. In our locality, affected women may also have an increased risk of pre-eclampsia. In affected women, the bile acid level is useful in assessing the risk of prematurity.

[Birth asphyxia and hypoxic ischemic encephalopathy, incidence and obstetric risk factors]

OBJECTIVE

Modern medical practice has changed dramatically during the past decades because of improved technology. Still, fetal surveillance during labor is relatively unchanged since 1960 s when fetal heart rate monitoring (FHR) became standard practice. Newborn infants are still suffering from birth asphyxia and in severe cases leading to hypoxic ischemic encephalopathy (HIE) which sometimes results in permanent neurological damage. The incidence of birth asphyxia and HIE in Iceland is unknown and so are the risk factors for severe asphyxia. The objective of this study was to assess the incidence, obstetric risk factors and the sequela of severe asphyxia at Landspitali university hospital (LSH).

MATERIAL AND METHODS

All term infants born at LSH from 1.1.1997- 31.12.2001 with birth asphyxia, defined as five minute Apgar score %lt;6, were included in the study (n=127). Clinical information were collected retrospectively from maternal records on maternal diseases during pregnancy, cardiotocogram (CTG), type of birth, the presence of meconium and operative delivery rates. Information was also collected regarding birth asphyxia and HIE in the neonatal period.

RESULTS

The incidence of birth asphyxia was 9.4/1000 live term births during the study period, with increasing incidence during the three last years. The incidence of HIE was 1.4/ 1,000 live term births. Severe maternal diseases during pregnancy were not a significant risk factor for asphyxia. The amniotic fluid was meconium stained in fifty percent of cases and the umbilical cord was wrapped around the fetal neck in 41% of cases. Abnormal CTG tracing was observed in 66% of cases in the study group and in 79% of the HIE cases. Operative deliveries were significantly more common in the study cohort compared with other deliveries at LSH at the same time: ventouse delivery 22% vs 6.8% (p<0,001), forceps delivery 6.3% vs 1,03% (p<0,001), emergency cesarean section 19.7% vs 11.4% ( p=0,008).

CONCLUSION

The incidence of birth asphyxia is higher in LSH compared with the incidence found in other studies. Signs of fetal distress on CTG and delivery with operative interventions are common. With current available methods to detect intrapartum asphyxia there is a poor correlation with CTG and the development of HIE after severe asphyxia. The presence of severe maternal diseases does not correlate with increased incidence of asphyxia, presumably due to increased surveillance of these pregnancies and a lower treshold for intervention during delivery. In low risk pregnancies there is a lack of appropriate methods with high sensitivity and specificity to detect intrapartum asphyxia.

Abdominal dystocia in a case of undetected intrauterine meconium peritonitis due to cystic fibrosis

The case of a 36 year-old primigravida is presented. After a normal anomaly scan at 22 weeks and a normal pregnancy, she went into labor at term. Dystocia due to massive abdominal distension complicated the second stage. The newborn girl had meconium peritonitis with colonic perforation and required colonic resection with colostomy. Genetic testing detected cystic fibrosis. In this case complex meconium peritonitis developed silently (without any clinical sign) after a normal anomaly scan. This has not been reported since the start of the widespread use of obstetric ultrasound. Late meconium peritonitis can escape detection and should be thought of in cases of unexpected abdominal distension causing dystocia.

Prise en charge précoce des enfants nés avec un liquide méconial: enquête dans les maternités françaises

The meconium aspiration syndrome is the first cause of respiratory distress in full term newborns. At birth, management includes systematical oropharyngeal suctioning, before and after shoulders delivery, followed by tracheal suction. During last 10 years, many trials were published which discuss again the value of this strategy.

AIM

To assess practices of the current management of births with a meconial amniotic liquid in the French maternities.

METHODS

Observational survey by written questionnaires sent to the 617 French maternities.

RESULTS

The rate of answers was of 54.3%. The incidence of the births presenting a meconial amniotic fluid was of 8.2%, complicated of meconium aspiration syndrome in 4.7%. In case of birth with presence of a meconial amniotic liquid, half of the maternities resorted systematically to oropharyngeal suctioning before shoulders delivery. A glottis exposition under laryngoscopy was practiced of principle for half of the newborn. Tracheal suctioning was achieved systematically in a quarter of the establishments. These techniques, with the exception of suctioning before clearing of the shoulders, were especially been achieved in a systematic way in the maternities of I and II A levels.

CONCLUSION

This survey shows the necessity of harmonization of the practices in France for the management of the births with a meconial amniotic liquid.

Regional pulmonary perfusion using model-free analysis of contrast-enhanced MRI in meconium-aspirated piglets

PURPOSE

To investigate if dynamic contrast-enhanced MRI in lungs could add new information to pulmonary hypertension in a newborn piglet model.

MATERIALS AND METHODS

Six newborn piglets were subjected to instillation of meconium following treatment with sildenafil. Before and after both of these events, dynamic contrast-enhanced MRI was performed to determine pulmonary blood flow (PBF) using a model-free deconvolution of the dynamic signal-time curve, together with invasive measurements of mean airway pressure (PAW), cardiac output (CO), and oxygenation index (OI).

RESULTS

Meconium instillation caused a significant increase in PAW (P < 0.05) accompanied by a marked increase in OI, the average PBF in the four lung regions (apical-anterior, apical-posterior, distal-anterior, and distal-posterior) decreased significantly by 33% (P < 0.001), but it did not significantly affect CO. On the other hand, infusion of sildenafil caused a significant increase in CO (P < 0.01), and administration resulted mainly in an increased PBF in the distal parts of the lungs.

CONCLUSION

By using dynamic contrast-enhanced MRI, we demonstrated a marked decrease in PBF following instillation of meconium, which was not followed by an equivalent decrease in CO, suggesting that measurements of CO inadequately reflect the intrapulmonary changes in the blood circulation.

Induction of early meconium evacuation promotes feeding tolerance in very low birth weight infants

BACKGROUND

A delay in reaching full enteral feeding is linked to poorer outcome in preterm neonates. Meconium retention has been viewed as a cause of bowel dysfunction in very low birth weight infants (VLBWI). Thus, adequate evacuation of meconium could help to promote feeding tolerance.

OBJECTIVES

Our goal was to determine the effect of the induction of early meconium evacuation on feeding tolerance in VLBWI.

METHODS

An observational study involving two subsequent periods was performed in inborn infants with birth weights of <1,500 g, before (control) and after (study) the induction of early meconium evacuation by routine glycerin enema. The total duration of these periods was from January 2003 to December 2005. To evaluate feeding tolerance, we measured time to achieve full enteral feeding. Complications such as sepsis and necrotizing enterocolitis were compared.

RESULTS

The study group achieved full enteral feeding significantly faster than the control group (hazard ratio (HR) = 2.9; 95% confidence interval (CI) = 1.8-4.8), and this effect was more definite in infants with a birth weight of <1,000 g (HR = 4.6; 95% CI = 1.9-11.1). The study group passed first meconium faster than the control group (median = 1.4 vs. 3.7 days; p < 0.001). Sepsis, especially as determined by positive culture in central venouscatheter, was significantly reduced in the study group (7.7 vs. 27.8%; p = 0.02).

CONCLUSIONS

The induction of early meconium evacuation had a significantly positive effect on feeding tolerance and sepsis prevention in VLBWI.

Alpha-1-antitrypsin and IgA in serial meconium and faeces of healthy breast-fed newborns

BACKGROUND

Meconium is a series of layers formed in the foetal intestine from the 12th week of gestation. High content of meconial alpha-1-antitrypsin (AAT), decreasing within the first several days of extrauterine life appears to reflect the meconium clearance of the gut. At birth, IgA is not present in the meconium and breast-fed infants receive this antibody postnatally with human milk. The aim of the study was to determine changes in AAT concentrations, functional activity of that inhibitor expressed as trypsin inhibitory capacity (TIC) and IgA concentration in serial meconium and faeces, as endogenous biochemical markers discriminating between faeces portions formed in intrauterine and extrauterine life periods of healthy breast-fed newborns.

METHODS

A group of 24 healthy breast-fed newborns delivered by spontaneous labour were studied prospectively during the first 4 days of postnatal life. AAT and IgA concentrations in the newborn's meconial and faecal samples and IgA concentration in mother's milk samples taken on the third day after delivery, were determined by radial immunodiffusion. TIC was assessed using BAPNA (N-benzoyl-DL-arginine-p-nitroanilide).

RESULTS

The medians (range) of AAT concentrations in milligrams per gram of dry meconium or faeces were: 68.8(29.2-138.4) (day 1), 56.9 (30.8-112.8) (day 2), 26.2 (6.8-80.7) (day 3), and 6.6 (1.4-27.1) (day 4). The medians (range) of TIC in milligrams of trypsin/g dry mass of meconium or faeces were: 0.76 (0.33-1.79) (day 1), 0.44 (0.17-1.08) (day 2), 0.16 (0.03-0.56) (day 3), and 0.03 (0-0.11) (day 4). The median (range) of IgA concentration in mothers' milk was 715 mg/dl (420-890). IgA was absent in meconium portions from the first day of life while on the successive days the medians (range) of IgA concentration in mg/g dry mass of meconium and faeces were as follows: 0 (0-2.90) (day 2), 2.50 (1.10-9.60) (day 3), 7.05 (4.10-30.60) (day 4). On day 4 of extrauterine life a negative correlation was found between AAT and IgA concentrations in faeces of the newborns (r = -0.46) and a positive correlation was seen between IgA concentrations in faeces and milk (r = 0.93).

CONCLUSIONS

Analyses of the systematic decrease in AAT and increase of IgA concentration in serial portions of meconium and faeces over the first days of extrauterine life of breast-fed newborns can date newborn's faeces portions formed during intrauterine and extrauterine maturation. AAT deposited in foetal intestine is an active antiprotease.

Chronic prenatal ethanol exposure and increased concentration of fatty acid ethyl esters in meconium of term fetal Guinea pig

In humans, the occurrence of prenatal exposure to ethanol is difficult to validate objectively. Increased concentration of fatty acid ethyl esters (FAEE) in the meconium of the newborn may be a biomarker of prenatal ethanol exposure. The validity of this proposed biomarker was tested in pregnant guinea pigs that received chronic oral administration of 4 g ethanol/kg maternal body weight/day (n=8), isocaloric-sucrose/pair-feeding (n=8) or water (n=2) throughout gestation. At gestational day 65 (term, gestational day 66 to 69), each dam and her offspring were euthanized, and meconium was collected from the term fetal large intestine. Eight individual FAEE (lauric, myristic, palmitic, palmitoleic, stearic, oleic, linolenic and arachidonic AEE) were measured by gas chromatography--flame ionization detection and confirmed by gas chromatography--mass spectrometry. The chronic maternal ethanol regimen decreased fetal body weight and brain weight. There was virtually no measurable FAEE in the meconium for the water group (n=3 fetuses). For meconium of the ethanol offspring (n=25 fetuses) compared with the sucrose offspring (n=23 fetuses), the total FAEE concentration was 8-fold higher; and lauric, palmitic, stearic and oleic AEE concentrations were at least 5-fold higher for the ethanol group. The data indicate that fetal meconium FAEE constitute a biomarker of prenatal ethanol exposure for a maternal ethanol regimen that restricts fetal development, with an inverse relationship between meconium total FAEE concentration and both body weight and brain weight.

Fatty acid ethyl esters in meconium: are they biomarkers of fetal alcohol exposure and effect?

BACKGROUND

Biomarkers of fetal exposure to alcohol are important to establish so that early detection and intervention can be made on these infants to prevent undesirable outcomes. The aim of this study was to analyze long-chain fatty acid ethyl esters (FAEEs) in meconium as potential biomarkers of fetal alcohol exposure and effect.

METHODS

Fatty acid ethyl esters were analyzed in the meconium of 124 singleton infants by positive chemical ionization gas chromatography/mass spectrometry (GC/MS) and correlated to maternal ethanol use.

RESULTS

A total of 124 mother/infant dyads were enrolled in the study: 31 were in the control group and 93 were in the alcohol-exposed group. The incidence (28% vs 9.7%, p = 0.037) of ethyl linoleate detected in meconium was significantly higher in the alcohol-exposed groups than the control groups. Similarly, when the concentrations of ethyl linoleate in meconium were grouped (trichotomized), there was a significant linear by linear association between alcohol exposure and group concentrations of ethyl linoleate (p = 0.013). Furthermore, only alcohol-exposed infants were found in the group with the highest ethyl linoleate concentration. The sensitivity of ethyl linoleate in detecting prenatal alcohol exposure was only 26.9%, and its specificity and positive predictive value were 96.8 and 96.2%, respectively. There was no significant correlation between the concentration of ethyl linoleate in meconium and absolute alcohol consumed (oz) per drinking day across pregnancy, although a trend toward a positive correlation is seen at lower amounts of alcohol consumed. Among the polyunsaturated, long-chain FAEEs, there was weak evidence that the incidence (21.5% vs 6.5%, p = 0.057) and concentration (p = 0.064) of ethyl arachidonate (AA) were significantly higher in the alcohol-exposed groups than the control groups. Ethyl linolenate and ethyl docosahexanoate (DHA) in meconium were found only in the alcohol group, although not at statistically significant levels. Highly significant correlations were found among the concentrations of ethyl linoleate, ethyl linolenate, ethyl AA, and ethyl DHA in meconium (correlations ranged between rs = 0.203, p = 0.024; and rs = 0.594, p < 0.001).

CONCLUSION

We conclude that FAEEs in meconium, particularly ethyl linoleate and ethyl AA, are biomarkers of high specificity for prenatal exposure to alcohol in newborn infants. We also propose that ethyl AA and DHA could be potential biomarkers of fetal alcohol effects on the developing fetal brain and should be investigated further.

Echogenic foci in the dilated fetal colon may be associated with the presence of a rectourinary fistula

Intraintestinal meconium calcification in the fetus and newborn is a rare finding, occurring in patients with intestinal obstruction. The intraluminal location of the enterolithiasis enables differentiation from calcifications that are secondary to bowel perforation and meconium peritonitis. We report on a term male neonate with VACTERL (vertebral defects, imperforate anus, cardiac anomalies, tracheoesophageal fistula, renal anomalies, limb anomalies) association and rectourethral fistula, in whom enterolithiasis was documented by prenatal ultrasound imaging at 21 weeks' gestation. A review of the literature and a summary of all previously described cases of neonates with intraluminal meconium calcifications are provided. Prenatal ultrasonographic detection of enterolithiasis in fetuses with anal atresia may indicate the presence of an enterourinary fistula.