Alcohol use in pregnancy, craniofacial features, and fetal growth

Sexually dimorphic effects of prenatal alcohol exposure on the murine skeleton

BACKGROUND

Prenatal alcohol exposure (PAE) can result in lifelong disabilities known as foetal alcohol spectrum disorder (FASD) and is associated with childhood growth deficiencies and increased bone fracture risk. However, the effects of PAE on the adult skeleton remain unclear and any potential sexual dimorphism is undetermined. Therefore, we utilised a murine model to examine sex differences with PAE on in vitro bone formation, and in the juvenile and adult skeleton.

METHODS

Pregnant C57BL/6J female mice received 5% ethanol in their drinking water during gestation. Primary calvarial osteoblasts were isolated from neonatal offspring and mineralised bone nodule formation and gene expression assessed. Skeletal phenotyping of 4- and 12-week-old male and female offspring was conducted by micro-computed tomography (µCT), 3-point bending, growth plate analyses, and histology.

RESULTS

Osteoblasts from male and female PAE mice displayed reduced bone formation, compared to control (≤ 30%). Vegfa, Vegfb, Bmp6, Tgfbr1, Flt1 and Ahsg were downregulated in PAE male osteoblasts only, whilst Ahsg was upregulated in PAE females. In 12-week-old mice, µCT analysis revealed a sex and exposure interaction across several trabecular bone parameters. PAE was detrimental to the trabecular compartment in male mice compared to control, yet PAE females were unaffected. Both male and female mice had significant reductions in cortical parameters with PAE. Whilst male mice were negatively affected along the tibial length, females were only distally affected. Posterior cortical porosity was increased in PAE females only. Mechanical testing revealed PAE males had significantly reduced bone stiffness compared to controls; maximum load and yield were reduced in both sexes. PAE had no effect on total body weight or tibial bone length in either sex. However, total growth plate width in male PAE mice compared to control was reduced, whilst female PAE mice were unaffected. 4-week-old mice did not display the altered skeletal phenotype with PAE observed in 12-week-old animals.

CONCLUSIONS

Evidence herein suggests, for the first time, that PAE exerts divergent sex effects on the skeleton, possibly influenced by underlying sex-specific transcriptional mechanisms of osteoblasts. Establishing these sex differences will support future policies and clinical management of FASD.

The role of general practitioners in Reunion in detecting alcohol use in pregnant women and identifying fetal alcohol spectrum disorder: a qualitative study

BACKGROUND

Fetal Alcohol Spectrum Disorder (FASD) is the leading cause of non-genetic intellectual disability and social maladjustment in children. International guidelines recommend abstinence from alcohol during pregnancy. Réunion is the most affected of all French regions with an estimated Fetal Alcohol Spectrum (FAS) prevalence of 1.2‰ births. General practitioners (GPs) are at the forefront of identifying patients with FASD.

OBJECTIVE

To understand how GPs identify FASD.

METHODS

Qualitative study using a grounded theory approach, through semi-structured face-to-face interviews with GPs. Interviews were conducted with the aim of reaching theoretical saturation. These were transcribed verbatim and then analyzed by four researchers to ensure triangulation of the data.

RESULTS

GPs reported barriers to the identification of FASD: challenges in overcoming social taboos and paradoxical injunctions, the influence of limited knowledge and experience, non-specific and highly variable symptoms, ambiguous classification and method of diagnosis involving the mobilization of a multidisciplinary team and lengthy consultations. Conversely, they felt competent to identify neurodevelopmental disorders of any cause, but were concerned about the long waiting time to access specialized care. From the perspective of GPs, it is crucial to prioritize promotion and training aimed at improving the identification and coordination of care pathways for children diagnosed with neurodevelopmental disorders, such as FASD.

A systematic review: facial, dental and orthodontic findings and orofacial diagnostics in patients with FASD

Background

The fetal alcohol spectrum disorder is a group of developmental disorders caused by maternal alcohol consumption. Patients with fetal alcohol syndrome show abnormal orofacial features. This review presents an overview over the facial, oral, dental or orthodontic findings and diagnostic tools concerning these features.

Methods

For this systematic review Cochrane, Medline and Embase databases were considered and the review was performed according to the PRISMA checklist. Two independent reviewers evaluated all studies and recorded results in a summary of findings table. Risk of bias was analyzed via Quadas-2 checklist.

Results

61 studies were eligible for inclusion. All included studies were clinical studies. Methods and results of the studies were not comparable, guidelines or methods for the detection of FASD varied across studies. Facial features most often measured or found as distinguishing parameter were: palpebral fissure length, interpupillary or innercanthal distance, philtrum, upper lip, midfacial hypoplasia or head circumference.

Conclusions

This review shows that to date a multitude of heterogeneous guidelines exists for the diagnosis of FASD. Uniform, objective diagnostic criteria and parameters for the orofacial region in FASD diagnosis are needed. A bio database with values and parameters for different ethnicities and age groups should be made available for diagnosis.

Serum concentrations of IGF-I/IGF-II as biomarkers of alcohol damage during foetal development and diagnostic markers of Foetal Alcohol Syndrome

Foetal Alcohol Syndrome (FAS) is the most deleterious health effect derived from alcohol consumption during pregnancy and is placed at the end of the Foetal Alcohol Spectrum Disorders (FASD). Few studies have proposed potential molecular biomarkers of physical and neurological damage associated with prenatal alcohol exposure. We prospectively recruited 55 children from 8 to 12 years old, with a prenatal assessment for ethanol exposure using meconium analysis of fatty acid ethyl esters (FAEE). The control group was established for FAEE < 2 nmol/g (n = 31) and a Prenatal Ethanol Exposure (PEE) group for FAEEs > 2 nmol/g (n = 33). Moreover, 98 children adopted from Eastern European Countries (EEC) were also recruited to evaluate FASD diagnosis comprising 31 cases with complete FAS, 42 with partial FAS, 6 with ARBD and 5 with ARND. Serum values of IGF-I and IGF-II for all children recruited were determined by immunoassay. Anthropometric and neurocognitive evaluation showed severe impairments in FAS children, moderate effects in PEE and no harmful effects in the control group with no prenatal exposure to alcohol. Analysis of IGF-I and IGF-II serum concentrations revealed that FASD from EEC as well as PEE children showed significantly lower concentrations of both IGF-I and IFG-II than the control group and reference values. Moreover, Spearman correlations showed a significant effect of IGF-I on anthropometric measurements in girls, whereas IGF-II affected the neuropsychological variables in both genders. These findings validate the use of growth factors IGF-I and IGF-II as surrogate biomarkers of damage induced by prenatal exposure to ethanol and could be used in the diagnosis of foetal alcohol spectrum disorders.

Risks and guidelines for the consumption of alcohol during pregnancy

Daily average intake of alcohol during pregnancy has consistently been associated with short term adverse outcomes such as miscarriage, preterm birth and intrauterine growth restriction, a large variety of malformations, as well as long term adverse outcomes such as foetal alcohol syndrome, mental retardation and general impairment of cognitive functions including intelligence, attention, learning abilities as well as social and behavioural functions. Weekly average consumption and alcohol binge drinking (usually defined as ≥ 5 drinks on a single occasion) independently of high daily average intake has not been consistently associated with short and long term adverse outcomes. Health authorities in most countries recommend that pregnant women completely abstain from alcohol. Even so, many health professionals including doctors, midwives and nurses do not provide information to pregnant women in accordance with the official recommendations, although a large proportion of women of child bearing age and pregnant women drink alcohol, especially before recognition of pregnancy. The discrepancy between guidelines and the information practice of health personnel is likely to continue to exist because guidelines of abstinence are not clearly evidence-based and not in line with current focus on autonomy and informed choice for patients, and because guidelines do not consider the everyday clinical communication situation.

Prenatal ethanol exposure and placental hCG and IGF2 expression

INTRODUCTION

Fetal alcohol spectrum disorder (FASD) is the main cause of preventable non-genetic mental retardation. Diagnosis of prenatal exposure to ethanol (PEE) is based on questionnaires and biomarkers in perinatal matrices. Early diagnosis of FASD is important to mitigate secondary disabilities that will arise later in life. It is important to identify biomarkers related to cellular damage caused by PEE. The main objective was to identify novel candidate biomarkers from placental tissue using an in vitro model of exposure to ethanol and to support it in placental tissue obtained from pregnancies with PEE assessed by fatty acid esters in meconium samples.

METHODS

First, hormone production was examined using two different human trophoblast cell lines, JEG3 and BeWo. Viable cell count by exclusion method was analyzed and human chorionic gonadotrophin (hCG) and insulin-like growth factor 2 (IGF2) were quantified by Western blot and ELISA. Second, these techniques were used in protein lysates from human placentas from pregnancies with and without exposure to ethanol.

RESULTS

Both trophoblast cell lines showed a decrease in cell viability accompanied with apoptosis activation after a chronic ethanol treatment. Moreover, we showed an increase in the secretion of hCG and IGF2 in a dose-dependent manner. Interestingly, this increase was also observed in a set of human placenta tissue from fetuses exposed prenatally to ethanol.

DISCUSSION

Ethanol exposure during pregnancy causes placenta cell damage, so altering its normal function. The specific hCG and IGF2 release pattern is a candidate surrogated biomarker of the damage due to PEE.

Ethanol cytotoxic effect on trophoblast cells

Prenatal ethanol exposure may cause both, altered fetal neurodevelopment and impaired placental function. These disturbances can lead to growth retardation, which is one of the most prevalent features in Fetal Alcohol Syndrome (FAS). It is not known whether there is a specific pattern of cytotoxicity caused by ethanol that can be extrapolated to other cell types. The aim of this study was to determine the cytotoxic effects caused by sustained exposure of trophoblast cells to ethanol. The cytotoxic effect of sustained exposure to standard doses of ethanol on an in vitro human trophoblast cell line, JEG3, was examined. Viable cell count by exclusion method, total protein concentration, lactate dehydrogenase (LDH) activity and activation of apoptotic markers (P-H2AX, caspase-3 and PARP-1) were determined. Sustained exposure to ethanol decreased viable cell count and total protein concentration. LDH activity did not increased in exposed cells but apoptotic markers were detected. In addition, there was a dose-dependent relationship between ethanol concentration and apoptotic pathways activation. Sustained ethanol exposure causes cellular cytotoxicity by apoptotic pathways induction as a result of DNA damage. This apoptotic induction may partially explain the altered function of placental cells and the damage previously detected in other tissues.

Head circumference at birth and exposure to tobacco, alcohol and illegal drugs during early pregnancy

AIMS

We aimed to assess the effects of exposure to tobacco smoke, alcohol and illegal drugs during early pregnancy on the head circumference (HC) at birth of otherwise healthy neonates.

METHODS

A follow-up study from the first trimester of pregnancy to birth was carried out in 419 neonates. An environmental reproductive health form was used to record data of substance exposure obtained during the first obstetric visit at the end of the first trimester. A multiple linear regression model was created for this purpose.

RESULTS

Alcohol intake during pregnancy and medical ionizing radiation exposure were the most significant predictors of HC. The mothers' alcohol consumption increased with the mothers' and fathers' education level, net family income and fathers' alcohol consumption. In contrast, maternal smoking decreased with increasing mothers' and fathers' education level and net family income. About 13% of the surveyed embryos were exposed to illegal drugs.

CONCLUSIONS

Mild to moderate alcohol consumption diminishes the at-birth HC of theoretically healthy newborns in a linear form. There was no threshold dose. We perceived a need for increasing the awareness, and for training, of health care professionals and parents, in regard to risks of alcohol consumption and for recommending abstinence of these substances in both parents during pregnancy. It should also be remembered that medical ionizing radiation should be performed only during the first half of the cycle in fertile women. We think that our study has an important social impact as it affords data for implementing policies for promoting "healthy pregnancies".

Zebrafish embryos and larvae: a new generation of disease models and drug screens

Technological innovation has helped the zebrafish embryo gain ground as a disease model and an assay system for drug screening. Here, we review the use of zebrafish embryos and early larvae in applied biomedical research, using selected cases. We look at the use of zebrafish embryos as disease models, taking fetal alcohol syndrome and tuberculosis as examples. We discuss advances in imaging, in culture techniques (including microfluidics), and in drug delivery (including new techniques for the robotic injection of compounds into the egg). The use of zebrafish embryos in early stages of drug safety-screening is discussed. So too are the new behavioral assays that are being adapted from rodent research for use in zebrafish embryos, and which may become relevant in validating the effects of neuroactive compounds such as anxiolytics and antidepressants. Readouts, such as morphological screening and cardiac function, are examined. There are several drawbacks in the zebrafish model. One is its very rapid development, which means that screening with zebrafish is analogous to "screening on a run-away train." Therefore, we argue that zebrafish embryos need to be precisely staged when used in acute assays, so as to ensure a consistent window of developmental exposure. We believe that zebrafish embryo screens can be used in the pre-regulatory phases of drug development, although more validation studies are needed to overcome industry scepticism. Finally, the zebrafish poses no challenge to the position of rodent models: it is complementary to them, especially in early stages of drug research.

Zebrafish embryo development in a microfluidic flow-through system

The zebrafish embryo is a small, cheap, whole-animal model which may replace rodents in some areas of research. Unfortunately, zebrafish embryos are commonly cultured in microtitre plates using cell-culture protocols with static buffer replacement. Such protocols are highly invasive, consume large quantities of reagents and do not readily permit high-quality imaging. Zebrafish and rodent embryos have previously been cultured in static microfluidic drops, and zebrafish embryos have also been raised in a prototype polydimethylsiloxane setup in a Petri dish. Other than this, no animal embryo has ever been shown to undergo embryonic development in a microfluidic flow-through system. We have developed and prototyped a specialized lab-on-a-chip made from bonded layers of borosilicate glass. We find that zebrafish embryos can develop in the chip for 5 days, with continuous buffer flow at pressures of 0.005-0.04 MPa. Phenotypic effects were seen, but these were scored subjectively as 'minor'. Survival rates of 100% could be reached with buffer flows of 2 µL per well per min. High-quality imaging was possible. An acute ethanol exposure test in the chip replicated the same assay performed in microtitre plates. More than 100 embryos could be cultured in an area, excluding infrastructure, smaller than a credit card. We discuss how biochip technology, coupled with zebrafish larvae, could allow biological research to be conducted in massive, parallel experiments, at high speed and low cost.

Large-scale analysis of acute ethanol exposure in zebrafish development: a critical time window and resilience

Background

In humans, ethanol exposure during pregnancy causes a spectrum of developmental defects (fetal alcohol syndrome or FAS). Individuals vary in phenotypic expression. Zebrafish embryos develop FAS-like features after ethanol exposure. In this study, we ask whether stage-specific effects of ethanol can be identified in the zebrafish, and if so, whether they allow the pinpointing of sensitive developmental mechanisms. We have therefore conducted the first large-scale (>1500 embryos) analysis of acute, stage-specific drug effects on zebrafish development, with a large panel of readouts.

Methodology/Principal Findings

Zebrafish embryos were raised in 96-well plates. Range-finding indicated that 10% ethanol for 1 h was suitable for an acute exposure regime. High-resolution magic-angle spinning proton magnetic resonance spectroscopy showed that this produced a transient pulse of 0.86% concentration of ethanol in the embryo within the chorion. Survivors at 5 days postfertilisation were analysed. Phenotypes ranged from normal (resilient) to severely malformed. Ethanol exposure at early stages caused high mortality (≥88%). At later stages of exposure, mortality declined and malformations developed. Pharyngeal arch hypoplasia and behavioral impairment were most common after prim-6 and prim-16 exposure. By contrast, microphthalmia and growth retardation were stage-independent.

Conclusions

Our findings show that some ethanol effects are strongly stage-dependent. The phenotypes mimic key aspects of FAS including craniofacial abnormality, microphthalmia, growth retardation and behavioral impairment. We also identify a critical time window (prim-6 and prim-16) for ethanol sensitivity. Finally, our identification of a wide phenotypic spectrum is reminiscent of human FAS, and may provide a useful model for studying disease resilience.

Prevalence and epidemiologic characteristics of FASD from various research methods with an emphasis on recent in-school studies

Researching the epidemiology and estimating the prevalence of fetal alcohol syndrome (FAS) and other fetal alcohol spectrum disorders (FASD) for mainstream populations anywhere in the world has presented a challenge to researchers. Three major approaches have been used in the past: surveillance and record review systems, clinic-based studies, and active case ascertainment methods. The literature on each of these methods is reviewed citing the strengths, weaknesses, prevalence results, and other practical considerations for each method. Previous conclusions about the prevalence of FAS and total FASD in the United States (US) population are summarized. Active approaches which provide clinical outreach, recruitment, and diagnostic services in specific populations have been demonstrated to produce the highest prevalence estimates. We then describe and review studies utilizing in-school screening and diagnosis, a special type of active case ascertainment. Selected results from a number of in-school studies in South Africa, Italy, and the US are highlighted. The particular focus of the review is on the nature of the data produced from in-school methods and the specific prevalence rates of FAS and total FASD which have emanated from them. We conclude that FAS and other FASD are more prevalent in school populations, and therefore the general population, than previously estimated. We believe that the prevalence of FAS in typical, mixed-racial, and mixed-socioeconomic populations of the US is at least 2 to 7 per 1,000. Regarding all levels of FASD, we estimate that the current prevalence of FASD in populations of younger school children may be as high as 2-5% in the US and some Western European countries.

Alcohol consumption during pregnancy and the risk of early stillbirth among singletons

The purpose of this study is to investigate the association between maternal alcohol intake in pregnancy and the occurrence of early stillbirth using a retrospective cohort analysis of singleton births in Missouri that occurred in the period 1989 through 1997 (N=655,979). We used Cox proportional hazards regression to generate adjusted risk estimates for total, early, and late stillbirth associated with maternal alcohol intake and used the Robust Sandwich Estimator to adjust for intracluster correlations among sibships. Overall, a total of 3,508 counts of stillbirth were identified, yielding a stillbirth rate of 5.3 per 1,000. Among mothers who consumed alcohol during pregnancy, the stillbirth rate was 8.3 per 1,000. Mothers who consumed alcohol while pregnant were 40% more likely to experience stillbirth as compared with nondrinking mothers (adjusted hazards ratio=1.4, 95% confidence interval: 1.2-1.7). A dose-response relationship was evident; mothers who consumed five or more drinks per week during pregnancy experienced a 70% elevated risk of stillbirth compared with nondrinking mothers (adjusted hazards ratio=1.7; 95% confidence interval: 1.0-3.0). The risk of early stillbirth was 80% higher among drinking mothers compared with abstainers (adjusted hazards ratio=1.8; 95% confidence interval: 1.3-2.3). The elevated risks for both early and late stillbirth did not reach statistical significance when broken down by level of alcohol intake. In conclusion, maternal drinking during pregnancy is associated with an increased risk of early stillbirth. These findings underscore the need to reinforce current counseling strategies toward pregnant women and women who intend to conceive on the detrimental effects of alcohol use in pregnancy.

Dysmorphic and anthropometric outcomes in 6-year-old prenatally cocaine-exposed children

Dysmorphologic and anthropometric assessments were performed on 154 6-year-old children prenatally exposed to cocaine (PCE) and 131 high-risk controls (NCE) of similar race and social class. Adjusted mean height z scores demonstrated a dose-response with metahydroxybenzoylecgonine above a threshold of 100 ng/g of meconium and greater cocaine exposure predicted lower weight for height z score. Higher average alcohol exposure throughout pregnancy and 3rd trimester predicted lower head circumference and weight z scores, respectively. Severity of marijuana use also predicted lower height for age but greater weight for height. There was not an increased rate of minor anomalies among the PCE cohort, nor was a consistent phenotype identified. After controlling for covariates, higher average prenatal cigarette exposure predicted higher incidence of cranial facial abnormalities. First trimester alcohol exposure predicted greater rates of ear abnormalities and third trimester marijuana exposure predicted greater rates of chest and head shape abnormalities. These finding indicate that prenatal cocaine exposure has a negative effect on specific growth outcomes including standardized height and weight for height, but not a systematic pattern of structural abnormalities.

Maternal alcohol consumption during pregnancy and physical outcomes up to 5 years of age: a longitudinal study

AIM

To examine whether alcohol exposure in pregnancy affects weight and head circumference (HC) at birth and 5 years, and whether these effects are independent of cigarette exposure in pregnancy and social disadvantage.

STUDY DESIGN

The Mater-University Study of Pregnancy (MUSP) involves a prospective cohort of 8556 mothers who were enrolled at first antenatal visit. The quantity and frequency of alcohol consumption in early and late pregnancy and a measure of binge drinking in early pregnancy were recorded. Weight and HC were measured on children seen at birth and at 5 years. Level of cigarette use in early pregnancy and maternal age and level of education and family income were also measured.

RESULTS

Light and moderate alcohol consumption in early or later pregnancy had no independent effects on weight or HC at birth or 5 years. Binge drinking in early pregnancy was not associated with restricted HC, and there was no effect modification by concurrent cigarette use in early pregnancy. An apparent effect of alcohol in late pregnancy on birth weight was due to confounding by cigarette use, with social risk being an independent predictor.

CONCLUSION

Alcohol ingestion up to moderate levels in pregnancy was not associated with deficits in either weight or HC at birth or at 5 years.

New perspectives on the face in fetal alcohol syndrome: what anthropometry tells us

Fetal alcohol syndrome (FAS) refers to the adverse effects to the fetus from prenatal exposure to alcohol. Originally, the diagnosis of FAS was given only to those individuals that were the most severely affected. Since that time, it has become apparent that the effects of prenatal alcohol exposure are broad-based, and those individuals diagnosed with FAS represent the severe end of the continuum in their phenotypic expression. This study utilized 21 craniofacial anthropometric measurements on 100 prenatally exposed individuals to quantify the elements of the FAS facial phenotype and to extend the quantitative phenotype to individuals who exhibited less severe or incomplete manifestations of prenatal alcohol exposure.

The role of acetaldehyde in pregnancy outcome after prenatal alcohol exposure

It is not known why some heavy-drinking women give birth to children with alcohol-related birth defects (ARBD) whereas others do not. The objective of this study was to determine whether the frequency of elevated maternal blood acetaldehyde levels among alcoholics is in the range of ARBD among alcoholic women. MEDLINE was searched from 1980 to 2000 using the key words acetaldehyde, pharmacokinetics, and alcoholism for controlled trials reporting blood or breath acetaldehyde levels in alcoholics and nonalcoholics. Separately, using the key words fetal alcohol syndrome, epidemiology, prevalence, incidence, and frequency, articles were identified reporting ARBD incidences among the offspring of heavy drinkers. Of 23 articles reporting acetaldehyde levels in alcoholics, four met the inclusion criteria. Forty-three studies reported on the rate of ARBD in heavy drinkers, and 14 were accepted. Thirty-four percent of heavy drinkers had a child with ARBD, and 43% of chronic alcoholics had high acetaldehyde levels. The similar frequencies of high acetaldehyde levels among alcoholics and the rates of ARBD among alcoholic women provide epidemiologic support to the hypothesis that acetaldehyde may play a major role in the cause of ARBD.

Socio-economic disparities in preterm birth: causal pathways and mechanisms

Preterm birth is the leading cause of infant mortality in industrialised societies. Its incidence is greatly increased among the socially disadvantaged, but the reasons for this excess are unclear and have been relatively unexplored. We hypothesise two distinct sets of causal pathways and mechanisms that may explain social disparities in preterm birth. The first set involves chronic and acute psychosocial stressors, psychological distress caused by those stressors, increased secretion of placental corticotropin releasing hormone (CRH), changes in sexual behaviours or enhanced susceptibility to bacterial vaginosis and chorioamnionitis, cigarette smoking or cocaine use, and decidual vasculopathy. The second hypothesised pathway is a gene-environment interaction based on a highly prevalent mutation in the gene for methylenetetrahydrofolate reductase (MTHFR), combined with low folate intake from the diet and from prenatal vitamin supplements, consequent hyperhomocysteinemia, and decidual vasculopathy. We propose to test these hypothesised pathways and mechanisms in a nested case-control study within a prospectively recruited and followed cohort of pregnant women with singleton pregnancies who deliver at one of four Montreal hospitals that serve an ethnically and socio-economically diverse population. Following recruitment during the late first or early second trimester, participating women are seen at 24-26 weeks, when a research nurse obtains a detailed medical and obstetric history; administers several scales to assess chronic and acute stressors and psychological function; obtains blood samples for CRH, red blood cell and plasma folate, homocysteine, and DNA for the MTHFR mutation; and performs a digital and speculum examination to measure cervical length and vaginal pH and to obtain swabs for bacterial vaginosis and fetal fibronectin. After delivery, each case (delivery at < 37 completed weeks following spontaneous onset of labour or prelabour rupture of membranes) and two controls are selected for placental pathological examination, hair analysis of cotinine, cocaine, and benzoylecgonine, and analysis of stored blood and vaginal specimens. Statistical analysis will be based on multiple logistic regression and structural equation modelling, with sequential construction of models of potential aetiological determinants and covariates to test the hypothesised causal pathways and mechanisms. The research we propose should improve understanding of the factors and processes that mediate social disparities in preterm birth. This improved understanding should help not only in developing strategies to reduce the disparities but also in suggesting preventive interventions applicable across the entire socio-economic spectrum.

Estimating the prevalence of fetal alcohol syndrome. A summary

Since the late 1970s, many studies have reported on the prevalence of fetal alcohol syndrome (FAS), alcohol-related birth defects (ARBD), and alcohol-related neurodevelopmental disorders (ARND). The three main types of research methods used in these studies are passive surveillance, clinic-based studies, and active case ascertainment. This article describes each of these methods, including their strengths and weaknesses, and summarizes the estimated prevalence of FAS produced by each of these approaches. The maternal risk factors associated with FAS and other alcohol-related anomalies include advanced maternal age, low socioeconomic status, frequent binge drinking, family and friends with drinking problems, and poor social and psychological indicators. Overall, the available literature points to a prevalence rate of FAS of 0.5 to 2 cases per 1,000 births in the United States during the 1980s and 1990s.

Does alcohol increase the risk of preterm delivery?

We evaluated the association between alcohol intake during pregnancy and preterm delivery. Women attending routine antenatal care at Aarhus University Hospital, Denmark, from 1989-1991 and 1992-1996 were eligible. We included 18,228 singleton pregnancies in the analyses. We obtained prospective information on alcohol intake at 16 and 30 weeks of gestation, other lifestyle factors, maternal characteristics, and obstetrical risk factors from self-administered questionnaires and hospital files. For women with alcohol intake of 1-2, 3-4, 5-9, and > or =10 drinks/week the risk ratio (RR) of preterm delivery was 0.91 (95% CI = 0.76-1.08), 0.86 (95% CI = 0.64-1.15), 0.89 (95% CI = 0.52-1.52), and 2.93 (95% CI = 1.52-5.63), respectively, compared with intake of <1 drink/week at 16 weeks gestation, and 0.69 (95% CI = 0.56-0.86), 0.82 (95% CI = 0.60-1.13), 0.97 (95% CI = 0.58-1.64), and 3.56 (95% CI = 1.78-7.13) at 30 weeks. Adjustment for smoking habits, caffeine intake, age, height, pre-pregnant weight, marital status, occupational status, education, parity, chronic diseases, previous preterm delivery, mode of initiation of labor, and sex of the child did not change the conclusions, nor did restriction of the highest intake group to women drinking 10-14 drinks/week (RR = 3.41 (1.71-6.81) at 16 weeks and RR = 3.47 (1.64-7.35) at 30 weeks).

Socio-economic disparities in pregnancy outcome: why do the poor fare so poorly?

In this paper, we review the evidence bearing on socio-economic disparities in pregnancy outcome, focusing on aetiological factors mediating the disparities in intrauterine growth restriction (IUGR) and preterm birth. We first summarise what is known about the attributable determinants of IUGR and preterm birth, emphasising their quantitative contributions (aetiological fractions) from a public health perspective. We then review studies relating these determinants to socio-economic status and, combined with the evidence about their aetiological fractions, reach some tentative conclusions about their roles as mediators of the socio-economic disparities. Cigarette smoking during pregnancy appears to be the most important mediating factor for IUGR, with low gestational weight gain and short stature also playing substantial roles. For preterm birth, socio-economic gradients in bacterial vaginosis and cigarette smoking appear to explain some of the socio-economic disparities; psychosocial factors may prove even more important, but their aetiological links with preterm birth require further clarification. Research that identifies and quantifies the causal pathways and mechanisms whereby social disadvantage leads to higher risks of IUGR and preterm birth may eventually help to reduce current disparities and improve pregnancy outcome across the entire socio-economic spectrum.

Effects of moderate alcohol consumption on the central nervous system

The concept of moderate consumption of ethanol (beverage alcohol) has evolved over time from considering this level of intake to be nonintoxicating and noninjurious, to encompassing levels defined as "statistically" normal in particular populations, and the public health-driven concepts that define moderate drinking as the level corresponding to the lowest overall rate of morbidity or mortality in a population. The various approaches to defining moderate consumption of ethanol provide for a range of intakes that can result in blood ethanol concentrations ranging from 5 to 6 mg/dl, to levels of over 90 mg/dl (i.e., approximately 20 mM). This review summarizes available information regarding the effects of moderate consumption of ethanol on the adult and the developing nervous systems. The metabolism of ethanol in the human is reviewed to allow for proper appreciation of the important variables that interact to influence the level of exposure of the brain to ethanol once ethanol is orally consumed. At the neurochemical level, the moderate consumption of ethanol selectively affects the function of GABA, glutamatergic, serotonergic, dopaminergic, cholinergic, and opioid neuronal systems. Ethanol can affect these systems directly, and/or the interactions between and among these systems become important in the expression of ethanol's actions. The behavioral consequences of ethanol's actions on brain neurochemistry, and the neurochemical effects themselves, are very much dose- and time-related, and the collage of ethanol's actions can change significantly even on the rising and falling phases of the blood ethanol curve. The behavioral effects of moderate ethanol intake can encompass events that the human or other animal can perceive as reinforcing through either positive (e.g., pleasurable, activating) or negative (e.g., anxiolysis, stress reduction) reinforcement mechanisms. Genetic factors and gender play an important role in the metabolism and behavioral actions of ethanol, and doses of ethanol producing pleasurable feelings, activation, and reduction of anxiety in some humans/animals can have aversive, sedative, or no effect in others. Research on the cognitive effects of acute and chronic moderate intake of ethanol is reviewed, and although a number of studies have noted a measurable diminution in neuropsychologic parameters in habitual consumers of moderate amounts of ethanol, others have not found such changes. Recent studies have also noted some positive effects of moderate ethanol consumption on cognitive performance in the aging human. The moderate consumption of ethanol by pregnant women can have significant consequences on the developing nervous system of the fetus. Consumption of ethanol during pregnancy at levels considered to be in the moderate range can generate fetal alcohol effects (behavioral, cognitive anomalies) in the offspring. A number of factors--including gestational period, the periodicity of the mother's drinking, genetic factors, etc.--play important roles in determining the effect of ethanol on the developing central nervous system. A series of recommendations for future research endeavors, at all levels, is included with this review as part of the assessment of the effects of moderate ethanol consumption on the central nervous system.

Prenatal alcohol exposure and development at preschool age: main results of a French study

Very high levels of alcohol consumption during pregnancy are harmful for the central nervous system of the child and affect morphogenesis and growth. The aim of this study was to investigate the effects of moderate prenatal alcohol exposure on development at preschool age in a longitudinal study. Pregnant women were interviewed on their alcohol consumption during pregnancy at their first visit to the maternity hospital of Roubaix, France. The development of their 160 children was assessed at the age of 4 1/2. Multiple regression analyses indicated that consumption of 1.5 oz of absolute alcohol (approximately 3 drinks) or more during pregnancy was significantly related to a decrease of 7 points on the general cognitive index of the McCarthy scales, after controlling for confounders. This level of consumption was also related to a higher score on minor neurological anomalies, a lower height of the child, and a higher score on facial features. This level of 1.5 oz of absolute alcohol/day should not be interpreted as a biological threshold, because the study does not allow conclusions to be drawn regarding the effects of lower levels of alcohol consumption. Alcohol consumption during pregnancy can affect the development of the child, at levels well below those associated with fetal alcohol syndrome.

Moderate alcohol consumption during pregnancy and the incidence of fetal malformations: a meta-analysis

To determine whether there is an association between moderate alcohol consumption in the first trimester of pregnancy and increased risk of fetal malformations, we conducted a literature search using Medline (1966-present), PsycLit (1974-1995), and EMBASE (1988-1995). The following inclusion criteria were used to select the studies to be evaluated: 1) pregnant women; 2) moderate alcohol consumption (> 2 drinks/week to 2 drinks/day); 3) case-control or cohort studies; 4) presence of an abstainer group (0 to 2 drinks/wk); 5) outcome measures include major or minor malformations; 6) papers published in the English language. The exclusion criteria were: 1) studies in which moderate alcohol consumption could not be confirmed; 2) case reports, and editorials. The Methods section of each study was examined independently by two blinded investigators with a third investigator settling any disagreement. The number of malformations in the abstainer and moderate alcohol consuming groups in two by two tables. Out of 24 studies which met the inclusion criteria, only seven had extractable data. The included studies evaluated 130,810 pregnancy outcomes, with 24,007 in the moderate alcohol group and 106,803 in the control group. An overall Mantel-Haenszel odds ratio showed that the relative risk for fetal malformations was 1.01 with 95% confidence limits of 0.94 to 1.08 and a chi-square for homogeneity of 8.26 (p = 0.220). Quality of the studies did not correlate with their showing negative or positive association. Moderate alcohol consumption during the first trimester of pregnancy is not associated with increased risk of fetal malformations.

Alcohol consumption and pregnancy in the Mexican national addiction survey

In 1988, the General Directorate of Epidemiology and the Mexican Institute of Psychiatry conducted the first National Addiction Survey (ENA), providing regional and national data on alcohol, tobacco, and drug use. The ENA providing a subsample of women who have been pregnant at some time in their lives. There were 5,234 affirmative responses. Women were asked if they had suffered any of three adverse outcomes during their last pregnancy: spontaneous abortion, stillbirth, and congenital abnormalities. Prevalence of spontaneous abortion was 3.8%, stillbirth 1.2%, and congenital abnormalities 1.1 %. Multiple logistic-regression models were used to analyze the effect of alcohol consumption on these problems. Consumption during pregnancy was related only with the prevalence of congenital abnormalities, with prevalence odds of 3.4. Among habitual users during the last 12 months, oniy women in the highest use category showed an important relationship with the three problems mentioned. Follow-up studies on the Mexican population are recommended in order to obtain more conclusive findings.

Moderate prenatal alcohol exposure and psychomotor development at preschool age

OBJECTIVES

This study investigated the effect of moderate prenatal alcohol exposure on psychomotor development of preschool-age children in a longitudinal study.

METHODS

Pregnant women were interviewed about their alcohol consumption at their first visit to the maternity hospital in Roubaix, France. Alcohol consumption before pregnancy and during the first trimester was assessed with a structured questionnaire. The psychomotor development of 155 children of these women was assessed with the McCarthy scales of children's abilities when the children were about 4 1/2 years old.

RESULTS

Consumption of 1.5 oz of absolute alcohol (approximately three drinks) or more per day during pregnancy was significantly related to a decrease of 7 points in the mean score on the general cognitive index of the McCarthy scales, after gender, birth order, maternal education, score for family stimulation, family status, maternal employment, child's age at examination, and examiner were controlled for.

CONCLUSIONS

This study showed that moderate to heavy alcohol consumption during pregnancy, at levels well below those associated with fetal alcohol syndrome, has effects on children's psychomotor development.

Moderate alcohol consumption in pregnancy and subsequent left-handedness

Alcohol in high doses is neurotoxic to the developing brain but it is not yet settled whether small doses give rise to more subtle effects. The aim of the study was to establish whether a moderate intake of alcohol in pregnancy would increase the frequency of left-handedness in the offspring. Such an association could indicate a possible subtle prenatal neurotoxic effect. This was a follow-up study of a group of pregnant women who took part in a community trial in 1984 to 1987. Data on alcohol consumption were reported by consecutively sampled pregnant women in the 36th week of gestation. Hand preference for their offspring was reported by the mothers in a self-administered questionnaire when their children were 5 to 9 years old. Ninety-one percent participated in the follow-up study. The study showed that 9.1% of the children were left-handed, with a higher prevalence among boys (11.8%). Results showed a slightly higher frequency of being left-handed among children exposed to alcohol in fetal life, but the findings were not statistically significant at a 0.05 level.

Is moderate alcohol intake in pregnancy associated with the craniofacial features related to the fetal alcohol syndrome?

Social drinking in pregnancy is common in many countries despite the fact that alcohol in high doses has teratogenic properties. The public health implications would be appreciable if even moderate alcohol consumption were associated with embryonal or fetal maldevelopment. A presumably sensitive marker of an alcohol effect was used in this study, namely the fetal craniofacial features included in the Fetal Alcohol Syndrome. The study was based upon self-reported alcohol intake and photographs taken at birth or at 18 months of children born to mothers with a low or moderate alcohol intake during pregnancy. These women were selected during pregnancy by a two-stage sampling from all in well defined regions. Data were available concerning 323 pregnant women and some 200 to 220 children. A short palpebral fissure, a short nose to upper-lip distance and a broad root of the nose were expected to be associated with alcohol intake in early pregnancy, but such an association was only seen between binge drinking and a short palpebral fissure. No associations proved statistically significant at the 18-month examination and any association could merely be secondary to the known association between alcohol and birth weight.

Hon v. Stroh Brewery Company: what do we mean by "moderate" and "heavy" drinking?

Although widely used, drinking terms such as "light,"' "moderate," and "heavy" are unstandardized and, as a result, public health messages using these terms may convey confusing information. As an initial attempt in providing such standardization, the present study surveyed public definitions for these terms. "Light" drinking was operationally defined as 1.4-2.4 drinks/day; "moderate" drinking was defined as 2.5-3.6 drinks/day; and "heavy" drinking was defined as 3.7 drinks/day and above. These ranges, however, were dependent on the respondent's gender, age, socioeconomic status, and especially the respondent's self-reported tolerance. Males had a higher threshold of consumption for "moderate" and "heavy" drinking than women. Older respondents likewise assigned a higher threshold for these terms than younger respondents. As respondent income increased, the threshold for "heavy" drinking decreased. The heaviest drinkers had a higher threshold for assigning the "heavy" label than did any other group. Ethnicity did not significantly affect these ranges, and religion only affected the threshold for "heavy" drinking. Because reseachers ultimately rely on terms such as "moderate" or ":heavy" to communicate their findings to colleagues and the public, it would seem apposite for them to agree on operational definitions for such terms. It would also seem appropriate to consider the operational definitions the public uses when referring to these terms to promote credibility of research findings and appropriate changes in behavior.

An update on incidence of FAS: FAS is not an equal opportunity birth defect

The incidence of Fetal Alcohol Syndrome is now estimated at 0.97 cases per 1,000 live births in the general obstetric population and 4.3% among "heavy" drinkers. The general incidence is more than 20 times higher in the United States (1.95 per 1,000) compared to Europe and other countries (0.08 per 1,000). Within the United States, the incidence at sites characterized by low socioeconomic status, and African American or Native American background are about 10 times higher (2.29 cases per 1,000) compared to sites with a predominant middle/upper SES and Caucasian background (0.26 per 1,000). Based on racial background, the number of pregnant women in the U.S. giving birth to FAS children is 2,043 per year; if based on socioeconomic status, the number is slightly higher 2,366. Although race and SES are confounded in the U.S. studies, an examination of U.S. and European studies suggests that the major factor associated with FAS is low SES rather than racial background.

Change in alcohol, tobacco and coffee consumption in pregnant women: evolution between 1988 and 1992 in an area of high consumption

OBJECTIVE

Analyse the evolution of alcohol, tobacco and coffee consumption during pregnancy in a population characterized by a high level of consumption and a low socioeconomic situation.

STUDY DESIGN

Data were obtained from two studies done with the same protocol and questionnaire in the Roubaix Public Maternity Hospital in 1988 (176 women) and 1992 (235 women); the two periods were compared using univariate tests and multiple logistic regression to control for social factors.

RESULTS

Between 1988 and 1992, there was a clear decrease in alcohol consumption, a slight decrease in coffee consumption and an increase in tobacco use. These changes affected usual consumption as well as consumption during pregnancy. The increase in tobacco use was no longer significant after controlling for social factors. However, the decrease in alcohol consumption affected all women regardless of sociodemographic characteristics, and remained significant after controlling for these characteristics.

CONCLUSION

Several factors support the hypothesis that the decrease in the reported alcohol consumption is real, for consumptions in the low to moderate range. However, it is difficult to identify the role of the several factors involved in this evolution: behaviour of the general population, attitude among pregnant women, information and sensitization of prenatal care providers. Besides, one negative aspect needs to be considered: the stability of the incidence of fetal alcohol syndrome, probably reflecting the stability of the proportion of very heavy consumers.

Prenatal alcohol exposure, birthweight, and measures of child size from birth to age 14 years

OBJECTIVES

The purpose of the study was to examine the effect of prenatal alcohol exposure on offspring's weight, height, and head circumference from birth through 14 years of age.

METHODS

This longitudinal prospective study examined a cohort of approximately 500 offspring (oversampled for heavier drinkers and stratified for smoking from a population of 1529 women in prenatal care at the 5th gestational month) at birth; 8 and 18 months; and 4, 7, and 14 years of age. Covariates were examined by means of multiple regression. Birth size measures were also examined as predictors of 7-year neurodevelopmental outcomes.

RESULTS

Effects of alcohol were observed on weight, length, and head circumference at birth; these effects were not altered by adjustment for covariates including smoking. However, the birthweight effect is clearly transient: although alcohol effects remained observable at 8 months, they were not measurable thereafter through age 14 years.

CONCLUSIONS

In this population-based sample, neither birthweight nor any later size measure was as useful an indicator of the enduring effects of prenatal alcohol exposure as were certain neurodevelopmental outcomes.

In vitro effect of S-adenosyl methionine on ethanol embryopathy in the rat

S-adenosyl methionine (SAM) is a universal methyl donor for biological systems. Chronic consumption of ethanol results in depletion of available SAM and reduces its biosynthesis in the transmethylation pathway. Administration of excess SAM may reduce the embryopathic effects of ethanol. The in-vitro effects of SAM on ethanol embryopathy was investigated by culturing 9.5 day old whole rat embryos for 48 hours in ethanol alone (Group II), 0.05 mM SAM (Group III), ethanol + 0.05 mM SAM (Group IV), ethanol + 0.1 mM SAM (Group V), ethanol + 1 mM SAM (Group VI), and in ethanol + 3 mM SAM (Group VII). In Group VII embryos, cardiovascular, nervous, auditory, visual, craniofacial and musculoskeletal systems were retarded in development; crown-rump length, yolk-sac diameter, as well as morphological scores, were reduced compared to those in embryos treated with ethanol alone (Group II). There were, however, significant differences between Group II and Group IV embryos with respect to crown-rump length, yolk sac diameter and somite number. The mean crown-rump length, yolk sac diameter and somite number in Group II were 2.3 +/- 0.2, 2.8 +/- 0.3 and 22.4 +/- 3.5 respectively, compared to 2.6 +/- 0.2, 3.1 +/- 0.2 and 25.3 +/- 3.1 in Group IV. These results suggest that simultaneous administration of S-adenosyl methionine and ethanol may protect against the embryopathic effects of ethanol.

Smoking and drinking habits before and during pregnancy in Spanish women

STUDY OBJECTIVE

To investigate possible changes in smoking and drinking habits during pregnancy and to elucidate the sociodemographic factors associated with these changes in Spanish women.

DESIGN

A cross-sectional survey.

PARTICIPANTS AND SETTING

A total of 1004 pregnant women of between 12 and 18 weeks of gestation who were attending the antenatal clinic of the main regional hospital of Valencia (Spain) during 1989 were studied. All participants completed the study and only one eligible woman refused to participate when approached.

MEASUREMENTS AND MAIN RESULTS

Information was obtained by structured questionnaire (Euromac questionnaire), which included items on age, educational level, marital status, occupation, parity, previous and present smoking habits, and previous and present alcohol consumption. Women were asked about the consumption of cigarettes and alcohol for a typical week before they knew they were pregnant, and details of current consumption were obtained for the week before the interview. The number of drinks taken per week was later converted to the amount of absolute alcohol (in g). Sixty per cent of the women smoked and 72% drank alcohol before pregnancy. Forty eight per cent of smokers stopped smoking and 37% of drinkers stopped drinking alcohol during pregnancy. No sociodemographic factor showed an independent association with either smoking or drinking cessation. Only the number of cigarettes and the amount of alcohol consumed before pregnancy were identified as significant independent predictors for stopping.

CONCLUSIONS

Pregnant Spanish women seemed to stop smoking at about three times the rate found in Spanish women in the reproductive years. The sociodemographic variables usually associated with stopping smoking could not account for the high rate of quitting in these Spanish women, a rate higher than that in women from other developed countries. The high prevalence of smoking before pregnancy might explain not only the high rate of stopping smoking but also the absence of a well defined profile of "quitters". In our study, high levels of alcohol consumption were limited to a small group of pregnant women, and preventive efforts should be focused on this group.

Ratings of fetal alcohol syndrome facial features by medical providers and biomedical scientists

Medical providers, (obstetricians, pediatricians) and biomedical research scientists engaged in fetal alcohol research for many years evaluated facial photographs of newborns previously diagnosed clinically as having or not having fetal alcohol syndrome (FAS). Medical providers and biomedical scientists did not differ significantly in their ratings. Children independently diagnosed as having FAS were distinguished from non-FAS children by both groups. Providing raters with additional information about children (e.g., birth weight) did not alter judgements significantly. Raters were highly consistent in the ratings they assigned to children (r = 0.96). Accuracy was assessed using signal detection measures (e.g., likelihood ratio, d'). Based on these measures, the two occupational groups did not differ significantly, and rater accuracy was highly significant. Mean ratings were highly correlated with positive maternal Michigan Alcohol Screening Test scores (r = 0.84). These results suggest that the facial features associated with fetal alcohol exposure are readily identifiable, and this, in turn, implies that recognition problems need not be a major contributor to ascertainment of FAS.