Maternal fatty acid intake and fetal growth: evidence for an association in overweight women. The 'EDEN mother-child' cohort (study of pre- and early postnatal determinants of the child's development and health)

Breastfeeding is not a risk factor for clinical severity in Autism spectrum disorder in children from the ELENA cohort

Autism spectrum disorder (ASD) is a neurodevelopmental disorder that results from a complex interaction between genes and environment. Breastfeeding (BF) is thought to promote healthy cognitive development, and a body of research has suggested that it may also protect against ASD. Our objectives were to identify the relationship between the initiation and duration of BF and the severity of clinical presentation in ASD. Data were collected from 243 children with a confirmed diagnosis of ASD followed in the ELENA cohort. Clinical severity was measured according to multiple dimensions using standardised tools. The frequency of the initiation of BF was comparable to that of the general population and the rate of children still being breastfed at six months of age was higher. Our results did not indicate a contribution of initiation or duration of BF to the prevention of clinical severity of ASD. We discuss our results in the light of possible methodological limitations of previous reports of an association between BF and ASD.Clinical Trial Registration: NCT02625116.

Impact of Maternal Obesity on the Metabolism and Bioavailability of Polyunsaturated Fatty Acids during Pregnancy and Breastfeeding

Prenatal and postnatal development are closely related to healthy maternal conditions that allow for the provision of all nutritional requirements to the offspring. In this regard, an appropriate supply of fatty acids (FA), mainly n-3 and n-6 long-chain polyunsaturated fatty acids (LCPUFA), is crucial to ensure a normal development, because they are an integral part of cell membranes and participate in the synthesis of bioactive molecules that regulate multiple signaling pathways. On the other hand, maternal obesity and excessive gestational weight gain affect FA supply to the fetus and neonate, altering placental nutrient transfer, as well as the production and composition of breast milk during lactation. In this regard, maternal obesity modifies FA profile, resulting in low n-3 and elevated n-6 PUFA levels in maternal and fetal circulation during pregnancy, as well as in breast milk during lactation. These modifications are associated with a pro-inflammatory state and oxidative stress with short and long-term consequences in different organs of the fetus and neonate, including in the liver, brain, skeletal muscle, and adipose tissue. Altogether, these changes confer to the offspring a higher risk of developing obesity and its complications, as well as neuropsychiatric disorders, asthma, and cancer. Considering the consequences of an abnormal FA supply to offspring induced by maternal obesity, we aimed to review the effects of obesity on the metabolism and bioavailability of FA during pregnancy and breastfeeding, with an emphasis on LCPUFA homeostasis.

Computer-based tailored dietary counselling improves the nutrient adequacy of the diet of French pregnant women: a randomised controlled trial

During pregnancy, mothers-to-be should adapt their diet to meet increases in nutrient requirements. Pregnant women appear to be keener to adopt healthier diets, but are not always successful. The objective of the present study was to determine whether a guided, stepwise and tailored dietary counselling programme, designed using an optimisation algorithm, could improve the nutrient adequacy of the diet of pregnant women, beyond generic guidelines. Pregnant women (n 80) who attended Notre-Dame-de-Bon-Secours Maternity Clinic were randomly allocated to the control or intervention arm. Dietary data were obtained twice from an online 3-d dietary record. The nutrient adequacy of the diet was calculated using the PANDiet score, a 100-point diet quality index adapted to the specific nutrient requirements for pregnancy. Women were supplied with generic dietary guidelines in a reference booklet. In the intervention arm, they also received nine sets of tailored dietary advice identified by an optimisation algorithm as best improving their PANDiet score. Pregnant women (n 78) completed the 12-week dietary follow-up. Initial PANDiet scores were similar in the control and intervention arms (60·4 (sd 7·3) v. 60·3 (sd 7·3), P = 0·92). The PANDiet score increased in the intervention arm (+3·6 (sd 9·3), P = 0·02) but not in the control arm (-0·3 (sd 7·3), P = 0·77), and these changes differed between arms (P = 0·04). In the intervention arm, there were improvements in the probabilities of adequacy for α-linolenic acid, thiamin, folate and cholesterol intakes (P < 0·05). Tailored dietary counselling using a computer-based algorithm is more effective than generic dietary counselling alone in improving the nutrient adequacy of the diet of French women in mid-pregnancy.

Developmental trajectories of motor skills during the preschool period

Children with developmental coordination disorder also manifest difficulties in non-motor domains (attentional, emotional, behavioral and socialization skills). Longitudinal studies can help disentangle the complex relationships between the development of motor skills and other cognitive domains. This study aims to examine the contribution of early cognitive factors to changes in motor skills during the preschool period. Children (N = 1144) from the EDEN mother-child cohort were assessed for motor skills with the Copy Design task (NEPSY battery) and the parent-rated Ages and Stages Questionnaire (fine and gross motor skills scores) at ages 3 and 5-6 years. At 3 years, language skills were evaluated using tests from the NEPSY and ELOLA batteries. Emotional problems, conduct problems, inattention and hyperactivity symptoms, peer relationships and pro-social behavior were assessed with the Strengths and Difficulties Questionnaire (SDQ) also at 3 years. Linear and logistic regression models were performed to examine whether positive and negative changes in motor skills between 3 and 5-6 years are associated with specific cognitive skills at 3 years, while adjusting for a broad range of pre- and postnatal environmental factors. In the linear regression model, the SDQ Inattention symptoms score at 3 years was associated with negative changes in motor skills (standardized β = - 0.09, SD = 0.03, p value = 0.007) and language skills at 3 years were associated with positive changes in motor skills (standardized β = 0.05, SD = 0.02, p value = 0.041) during the preschool period. In logistic regression models, the SDQ Inattention symptoms score at 3 years was associated with a higher likelihood of a declining trajectory of motor skills (OR [95% CI] = 1.37 [1.02-1.84]). A higher language skills score at 3 years was associated with an increased likelihood of a resilient trajectory (1.67 [1.17-2.39]). This study provides a better understanding of the natural history of developmental coordination delays by identifying cognitive factors that predict changes in motor skills between the ages of 3 and 5-6 years.

Influence of the Urban Exposome on Birth Weight

BACKGROUND

The exposome is defined as the totality of environmental exposures from conception onwards. It calls for providing a holistic view of environmental exposures and their effects on human health by evaluating multiple environmental exposures simultaneously during critical periods of life.

OBJECTIVE

We evaluated the association of the urban exposome with birth weight.

METHODS

We estimated exposure to the urban exposome, including the built environment, air pollution, road traffic noise, meteorology, natural space, and road traffic (corresponding to 24 environmental indicators and 60 exposures) for nearly 32,000 pregnant women from six European birth cohorts. To evaluate associations with either continuous birth weight or term low birth weight (TLBW) risk, we primarily relied on the Deletion-Substitution-Addition (DSA) algorithm, which is an extension of the stepwise variable selection method. Second, we used an exposure-by-exposure exposome-wide association studies (ExWAS) method accounting for multiple hypotheses testing to report associations not adjusted for coexposures.

RESULTS

The most consistent statistically significant associations were observed between increasing green space exposure estimated as Normalized Difference Vegetation Index (NDVI) and increased birth weight and decreased TLBW risk. Furthermore, we observed statistically significant associations among presence of public bus line, land use Shannon's Evenness Index, and traffic density and birth weight in our DSA analysis.

CONCLUSION

This investigation is the first large urban exposome study of birth weight that tests many environmental urban exposures. It confirmed previously reported associations for NDVI and generated new hypotheses for a number of built-environment exposures. https://doi.org/10.1289/EHP3971.

Integrating Clinical and Epidemiologic Data on Allergic Diseases Across Birth Cohorts: A Harmonization Study in the Mechanisms of the Development of Allergy Project

The numbers of international collaborations among birth cohort studies designed to better understand asthma and allergies have increased in the last several years. However, differences in definitions and methods preclude direct pooling of original data on individual participants. As part of the Mechanisms of the Development of Allergy (MeDALL) Project, we harmonized data from 14 birth cohort studies (each with 3-20 follow-up periods) carried out in 9 European countries during 1990-1998 or 2003-2009. The harmonization process followed 6 steps: 1) organization of the harmonization panel; 2) identification of variables relevant to MeDALL objectives (candidate variables); 3) proposal of a definition for each candidate variable (reference definition); 4) assessment of the compatibility of each cohort variable with its reference definition (inferential equivalence) and classification of this inferential equivalence as complete, partial, or impossible; 5) convocation of a workshop to agree on the reference definitions and classifications of inferential equivalence; and 6) preparation and delivery of data through a knowledge management portal. We agreed on 137 reference definitions. The inferential equivalence of 3,551 cohort variables to their corresponding reference definitions was classified as complete, partial, and impossible for 70%, 15%, and 15% of the variables, respectively. A harmonized database was delivered to MeDALL investigators. In asthma and allergy birth cohorts, the harmonization of data for pooled analyses is feasible, and high inferential comparability may be achieved. The MeDALL harmonization approach can be used in other collaborative projects.

Maternal Pre-Pregnancy Obesity Attenuates Response to Omega-3 Fatty Acids Supplementation During Pregnancy

Maternal obesity is associated with adverse offspring outcomes. Inflammation and deficiency of anti-inflammatory nutrients like omega(n)-3 polyunsaturated fatty acids (PUFA) may contribute to these associations. Fetal supply of n-3 PUFA is dependent on maternal levels and studies have suggested that improved offspring outcomes are associated with higher maternal intake. However, little is known about how maternal obesity affects the response to n-3 supplementation during pregnancy. We sought to determine (1) the associations of obesity with PUFA concentrations and (2) if the systemic response to n-3 supplementation differs by body mass index (BMI). This was a secondary analysis of 556 participants (46% lean, 28% obese) in the Maternal-Fetal Medicine Units Network trial of n-3 (Docosahexaenoic acid (DHA) + Eicosapentaenoic acid (EPA)) supplementation, in which participants had 2g/day of n-3 (n = 278) or placebo (n = 278) from 19 to 22 weeks until delivery. At baseline, obese women had higher plasma n-6 arachidonic acid concentrations (β: 0.96% total fatty acids; 95% Confidence Interval (CI): 0.13, 1.79) and n-6/n-3 ratio (β: 0.26 unit; 95% CI: 0.05, 0.48) compared to lean women. In the adjusted analysis, women in all BMI groups had higher n-3 concentrations following supplementation, although obese women had attenuated changes (β = -2.04%, CI: -3.19, -0.90, interaction p = 0.000) compared to lean women, resulting in a 50% difference in the effect size. Similarly, obese women also had an attenuated reduction (β = 0.94 units, CI: 0.40, 1.47, interaction p = 0.046) in the n-6/n-3 ratio (marker of inflammatory status), which was 65% lower compared to lean women. Obesity is associated with higher inflammation and with an attenuated response to n-3 supplementation in pregnancy.

Fish Intake in Pregnancy and Offspring Metabolic Parameters at Age 9⁻16-Does Gestational Diabetes Modify the Risk?

Oily fish, an important source of marine n-3 long-chain polyunsaturated fatty acids (LCPUFA), has shown to reduce cardiometabolic risk in adults. Whether maternal fish intake affects offspring metabolic health is less established, especially among high-risk pregnancies. We aimed to examine the association of fish intake in pregnancy with offspring metabolic health who were either exposed or unexposed to gestational diabetes mellitus (GDM). Our study included 1234 mother-offspring dyads (608 with a GDM index pregnancy and 626 control dyads) nested within the Danish National Birth Cohort, which is a prebirth cohort. Maternal seafood and marine n-3 LCPUFA consumption was quantified by a food frequency questionnaire (gestational week 25) and a sub-sample with interview data (weeks 12 and 30). The offspring were clinically examined at 9–16 years, including a Dual energy X-ray Absorptiometry (DXA) scan and a fasting blood sample. We calculated multivariable effect estimates and 95% confidence intervals (CI) for anthropometric, adiposity, and metabolic parameters. The median (IQR) intake of total seafood was 23(24) g/day. We found largely no association for total seafood and marine n-3 LCPUFA with offspring metabolic parameters in either group. Using interview data, GDM-exposed women reporting no fish in week 12 and 30 (versus intake >2 times/week) had offspring with a higher Body Mass Index (BMI) (ratio of geometric means (RGM): 1.28, 95% CI: 1.06, 1.55), waist circumference (RGM: 1.22, 95% CI: 1.05, 1.40), triglycerides (RGM: 1.77, 95% CI: 1.03, 3.03), and homeostatic model assessment of insulin resistance HOMA-IR (RGM: 2.16, 95% CI: 1.17, 3.97). We found no associations of n-3 LCPUFA and seafood intake with offspring metabolic outcomes. However, GDM-exposed women who consistently reported eating no fish had offspring with a poorer metabolic profile. Fish intake in pregnancy may mitigate some adverse effects of intrauterine hyperglycemia, however, these findings need replication in better powered studies.

Sex differences in psychomotor development during the preschool period: A longitudinal study of the effects of environmental factors and of emotional, behavioral, and social functioning

We sought to determine the extent to which sex differences in psychomotor development during the preschool period can be explained by differential exposure to environmental factors and/or differences in emotional, behavioral, or social functioning. Children from the EDEN mother-child cohort were assessed for language, gross motor, and fine motor skills at 2, 3, and 5-6 years of age using parental questionnaires and neuropsychological tests. Structural equation models examining the associations between sex and language, gross motor, and fine motor skills at 2, 3, and 5-6 years were performed while adjusting for a broad range of pre- and postnatal environmental factors as well as emotional, behavioral and socialization difficulties. Girls (n = 492) showed better fine motor skills than boys (n = 563) at 2 years (Cohen's d = 0.67 in the fully adjusted models), at 3 years (d = 0.72), and to a lesser extent at 5-6 years (d = 0.29). Girls also showed better language skills at 2 years (d = 0.36) and 3 years (d = 0.37) but not at 5-6 years (d = 0.04). We found no significant differences between girls and boys in gross motor skills at 2, 3, or 5-6 years. Similar results were found in the models unadjusted and adjusted for pre- and postnatal environmental factors as well as emotional, behavioral, and socialization difficulties. Our findings are consistent with the idea that sex differences in fine motor and language skills at 2 and 3 years of age are not explained by differential exposure to environmental factors or by sex differences in emotional, behavioral, or social functioning.

To which extent social withdrawal at the age of 1 year is associated with IQ at 5-6 years old? Results of the EDEN mother-child cohort

The present study aims to determine to which extent social withdrawal at 1 year is associated with the child's IQ at the end of the preschool period. Children (N = 1045) from the EDEN mother-child cohort were assessed for social withdrawal behaviours at 1 year by trained midwives using the Alarm Distress BaBy (ADBB) scale. Midwives also examined infants' language and motor development at 1 year. At the age 5-6 years, IQ scores were based on the WPPSI-III. Linear regression models were used to determine the association between IQ and ADBB, adjusted for a broad range of pre- and postnatal environmental factors and for language and motor skills scores at 1 year. After adjusting for environmental factors, children with social withdrawal at 1 years (ADBB ≥5; N = 195) had significantly lower IQ scores at 5-6 years (-2.81 IQ points; p value 0.007) compared to children without social withdrawal (ADBB <5; N = 847). When motor and language skills at 1 year were included in the previous model, no association between social withdrawal and IQ at 5-6 years was found. Being socially withdrawn at 1 year is associated with lower IQ scores at 5-6 years. The potential influence of these developmental aspects on each other (withdrawal behaviour and language/motor skills) may occur early in development. Our results improve our understanding of the outcomes of early social withdrawal behaviour and call for early detection of delay in acquisition of language/motor skills among socially withdrawn young children.

Maternal plasma phosphatidylcholine polyunsaturated fatty acids during pregnancy and offspring growth and adiposity

BACKGROUND

Polyunsaturated fatty acids (PUFA) are essential for offspring development, but it is less clear whether pregnancy PUFA status affects growth and adiposity.

METHODS

In 985 mother-offspring pairs from the ongoing Singaporean GUSTO cohort, we analyzed the associations between offspring growth and adiposity outcomes until age 5 years and five PUFAs of interest, measured in maternal plasma at 26-28 weeks' gestation: linoleic acid (LA), arachidonic acid, α-linolenic acid, eicosapentaenoic acid, and docosahexaenoic acid (DHA). We measured fetal growth by ultrasound (n=924), neonatal body composition (air displacement plethysmography (n=252 at birth, and n=317 at age 10 days), and abdominal magnetic resonance imaging (n=317)), postnatal growth (n=979) and skinfold thicknesses (n=981). Results were presented as regression coefficients for a 5% increase in PUFA levels.

RESULTS

LA levels were positively associated with birthweight (β (95% CI): 0.04 (0.01, 0.08) kg), body mass index (0.13 (0.02, 0.25) kg/m²), head circumference (0.11 (0.03, 0.19) cm), and neonatal abdominal adipose tissue volume (4.6 (1.3, 7.8) mL for superficial subcutanous tissue, and 1.2 (0.1, 2.4) mL for internal tissue), but not with later outcomes. DHA levels, although not associated with birth outcomes, were related to higher postnatal length/height: 0.63 (0.09, 1.16) cm at 12 months and 1.29 (0.34, 2.24) cm at 5 years.

CONCLUSIONS

LA was positively associated with neonatal body size, and DHA with child height. Maternal PUFA status during pregnancy may influence fetal and child growth and adiposity.

Do developmental milestones at 4, 8, 12 and 24 months predict IQ at 5-6 years old? Results of the EDEN mother-child cohort

RATIONALE

The present study aims: (i) to determine how well developmental milestones at 4, 8, 12 and 24 months may predict IQ at 5-6 years old, (ii) to identify cognitive domains during the first two years that best predict later IQ and (iii) to determine whether children with IQ in the normal range at 5-6 years old may differ from disabled (IQ < 70) and gifted children (IQ > 130) with regard to their early cognitive development.

METHOD

The main developmental milestones were collected through self-administered questionnaires rated by parents at 4, 8, 12 and 24 months and through parental questionnaires administered by a trained interviewer and questionnaires completed following a medical examination at 12 months. These questionnaires were derived from the Brunet-Lézine Psychomotor Development Scale and they addressed several cognitive domains (gross and fine motor skills, language and socialization).

RESULTS

(i) Developmental milestones predict a substantial part of the later IQ variance from 24 months (R² ∼ 20%). (ii) Early language skills more strongly predict later IQ than the other cognitive domains. (iii) Several cognitive domains, but particularly language skills, predict disabled children at 5-6 years old (from the age of 8 months) and gifted children (from the age of 12 months).

DISCUSSION

The present study provides valuable information for early developmental assessment and could contribute to a better understanding of intellectual development.

Relationship between early language skills and the development of inattention/hyperactivity symptoms during the preschool period: Results of the EDEN mother-child cohort

BACKGROUND

This study aims to examine bidirectional relationships between children's language skills and Inattention/Hyperactivity (IH) symptoms during preschool.

METHOD

Children (N = 1459) from the EDEN mother-child cohort were assessed at ages 3 and 5.5 years. Language skills were evaluated using the WPPSI-III, NEPSY and ELOLA batteries. Children's behavior, including IH symptoms, was assessed using the parent-rated Strengths & Difficulties Questionnaire (SDQ). Using a Structural Equation Modeling (SEM) approach, we examined the relationship between language skills and IH symptoms, as well as potential mediating processes.

RESULTS

SEM analyses indicated a small negative effect of language skills at 3 years on ADHD symptoms at 5.5 years after adjusting for IH symptoms at 3 years (β =-0.12, SE = 0.04, p-value = 0.002). Interpersonal difficulties did not mediate the relationship between early language skills and later IH symptoms, nor was this association reduced after adjusting for a broad range of pre- and postnatal environmental factors and performance IQ. Among different language skills, receptive syntax at 3 years was most strongly related to IH symptoms at 5.5 years.

CONCLUSIONS

Poor language skills at age 3 may predict IH symptoms when a child enters primary school. Implications for the understanding and the prevention of the co-occurrence of language disorders and ADHD are discussed.

Human exposure to environmental contaminants and congenital anomalies: a critical review

Congenital anomalies are an important cause of infant mortality and disability. Developmental exposure to environmental contaminants is thought to increase the risk for congenital anomalies. Herein, we describe a critical review of the literature conducted between February and March 2014 yielding 3057 references from which 97 unique relevant articles published from 2003 through 2014 were evaluated. Common congenital anomalies including hypospadias, cryptorchidism, anogenital distance (AGD), congenital heart defects and oral clefts were well represented in the literature whereas other outcomes such as neural tube defects, limb deficiency defects and gastroschisis were rarely described. While definitions used for congenital anomalies and methods of ascertainment were usually consistent across studies, inconsistencies were frequently found in grouping of different congenital heart defects. Despite strong links between some congenital anomalies and parental occupation, these studies are unable to provide clear insight into the specific chemicals responsible owing to lack of direct measures of exposure. In comparison, data are mixed for contaminant exposures at concentrations representative of results from contemporary biomonitoring studies. Of the environmental contaminants studied, the association between phthalate exposures and developmental abnormalities of the male reproductive tract received the greatest attention. Important limitations of the literature studied relate to adequacy of sample size, absence of or weaknesses in exposure assessment methodologies, failure to account for biological plausibility and grouping of congenital anomalies with divergent mechanisms. We conclude that the literature is inadequate at this time to support a conclusion that exposure to environmental contaminants are or are not associated with increased risks for congenital anomalies in the general population.

Effect of ω-3 supplementation on placental lipid metabolism in overweight and obese women

BACKGROUND

The placentas of obese women accumulate lipids that may alter fetal lipid exposure. The long-chain omega-3 fatty acids (n–3 FAs) docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) alter FA metabolism in hepatocytes, although their effect on the placenta is poorly understood.

OBJECTIVE

We aimed to investigate whether n–3 supplementation during pregnancy affects lipid metabolism in the placentas of overweight and obese women at term.

DESIGN

A secondary analysis of a double-blind randomized controlled trial was conducted in healthy overweight and obese pregnant women who were randomly assigned to DHA plus EPA (2 g/d) or placebo twice a day from early pregnancy to term. Placental FA uptake, esterification, and oxidation pathways were studied by measuring the expression of key genes in the placental tissue of women supplemented with placebo and n–3 and in vitro in isolated trophoblast cells in response to DHA and EPA treatment.

RESULTS

Total lipid content was significantly lower in the placentas of overweight and obese women supplemented with n–3 FAs than in those supplemented with placebo (14.14 ± 1.03 compared with 19.63 ± 1.45 mg lipid/g tissue; P < 0.05). The messenger RNA expression of placental FA synthase (FAS) and diacylglycerol O-acyltransferase 1 (DGAT1) was negatively correlated with maternal plasma enrichment in DHA and EPA (P < 0.05). The expression of placental peroxisome proliferator–activated receptor γ (r = −0.39, P = 0.04) and its target genes DGAT1 (r = −0.37, P = 0.02) and PLIN2 (r = −0.38, P = 0.04) significantly decreased, with an increasing maternal n–3:n–6 ratio (representing the n–3 status) near the end of pregnancy. The expression of genes that regulate FA oxidation or uptake was not changed. Birth weight and length were significantly higher in the offspring of n–3-supplemented women than in those in the placebo group (P < 0.05), but no differences in the ponderal index were observed. Supplementation of n–3 significantly decreased FA esterification in isolated trophoblasts without affecting FA oxidation.

CONCLUSION

Supplementing overweight and obese women with n–3 FAs during pregnancy inhibited the ability of the placenta to esterify and store lipids. This trial was registered at clinicaltrials.gov as NCT00957476.

Cord Blood Methylmercury and Fetal Growth Outcomes in Baltimore Newborns: Potential Confounding and Effect Modification by Omega-3 Fatty Acids, Selenium, and Sex

BACKGROUND

Methylmercury (MeHg) may affect fetal growth; however, prior research often lacked assessment of mercury speciation, confounders, and interactions.

OBJECTIVE

Our objective was to assess the relationship between MeHg and fetal growth as well as the potential for confounding or interaction of this relationship from speciated mercury, fatty acids, selenium, and sex.

METHODS

This cross-sectional study includes 271 singletons born in Baltimore, Maryland, 2004-2005. Umbilical cord blood was analyzed for speciated mercury, serum omega-3 highly unsaturated fatty acids (n-3 HUFAs), and selenium. Multivariable linear regression models controlled for gestational age, birth weight, maternal age, parity, prepregnancy body mass index, smoking, hypertension, diabetes, selenium, n-3 HUFAs, and inorganic mercury (IHg).

RESULTS

Geometric mean cord blood MeHg was 0.94 μg/L (95% CI: 0.84, 1.07). In adjusted models for ponderal index, βln(MeHg) = -0.045 (g/cm(3)) × 100 (95% CI: -0.084, -0.005). There was no evidence of a MeHg × sex interaction with ponderal index. Contrastingly, there was evidence of a MeHg × n-3 HUFAs interaction with birth length [among low n-3 HUFAs, βln(MeHg) = 0.40 cm, 95% CI: -0.02, 0.81; among high n-3 HUFAs, βln(MeHg) = -0.15, 95% CI: -0.54, 0.25; p-interaction = 0.048] and head circumference [among low n-3 HUFAs, βln(MeHg) = 0.01 cm, 95% CI: -0.27, 0.29; among high n-3 HUFAs, βln(MeHg) = -0.37, 95% CI: -0.63, -0.10; p-interaction = 0.042]. The association of MeHg with birth weight and ponderal index was affected by n-3 HUFAs, selenium, and IHg. For birth weight, βln(MeHg) without these variables was -16.8 g (95% CI: -75.0, 41.3) versus -29.7 (95% CI: -93.9, 34.6) with all covariates. Corresponding values for ponderal index were -0.030 (g/cm(3)) × 100 (95% CI: -0.065, 0.005) and -0.045 (95% CI: -0.084, -0005).

CONCLUSION

We observed an association of increased MeHg with decreased ponderal index. There is evidence for interaction between MeHg and n-3 HUFAs; infants with higher MeHg and n-3 HUFAs had lower birth length and head circumference. These results should be verified with additional studies.

Periconceptional Seafood Intake and Fetal Growth

BACKGROUND

Previous reports of associations of maternal seafood intake with fetal growth were inconsistent. Further, little is known whether associations differ across seafood subtypes or fetal growth indices.

METHODS

Among 3141 participants of the Omega study, a pregnancy cohort study, we investigated associations of periconceptional shell, lean, and fatty fish intake with fetal growth indices. We categorised food frequency questionnaire reported seafood intake into frequencies of: <0.2 servings/month, 0.2 servings/month -<0.5 servings/week, 0.5-1 servings/week, and >1 servings/week. We abstracted birthweight, birth length, and head circumference from medical records. Using generalised linear models with a log link, the Poisson family, and robust standard errors, we estimated relative risks and 95% confidence intervals (CI) for low birthweight (LBW, <2500 g) and linear regression models to estimate mean differences for continuous fetal growth indices across seafood intake categories.

RESULTS

Medians (interquartile range) of shell, lean, and fatty fish intake were 0.3 (0-0.9), 0.5 (0-1.0), and 0.5 (0.1-1.0) servings/week, respectively. Lean fish intake of >1 servings/week (vs. <0.2 servings/month) was associated with a 2.2-fold higher risk of LBW (95% CI 1.2, 4.1). Shellfish intake of >1 servings/week (vs. <0.2 servings/month) was associated with a 0.6 kg/m(3) higher mean ponderal index (95% CI 0.0, 1.2 kg/m(3) ). There was no evidence for associations of total seafood or seafood subtype intake with other fetal growth indices.

CONCLUSIONS

Higher intakes of lean fish and shellfish were associated with a higher risk of LBW and higher mean ponderal index, respectively. Findings highlight the importance of considerations of seafood subtype in similar investigations.

Mother's education and the risk of preterm and small for gestational age birth: a DRIVERS meta-analysis of 12 European cohorts

BACKGROUND

A healthy start to life is a major priority in efforts to reduce health inequalities across Europe, with important implications for the health of future generations. There is limited combined evidence on inequalities in health among newborns across a range of European countries.

METHODS

Prospective cohort data of 75 296 newborns from 12 European countries were used. Maternal education, preterm and small for gestational age births were determined at baseline along with covariate data. Regression models were estimated within each cohort and meta-analyses were conducted to compare and measure heterogeneity between cohorts.

RESULTS

Mother's education was linked to an appreciable risk of preterm and small for gestational age (SGA) births across 12 European countries. The excess risk of preterm births associated with low maternal education was 1.48 (1.29 to 1.69) and 1.84 (0.99 to 2.69) in relative and absolute terms (Relative/Slope Index of Inequality, RII/SII) for all cohorts combined. Similar effects were found for SGA births, but absolute inequalities were greater, with an SII score of 3.64 (1.74 to 5.54). Inequalities at birth were strong in the Netherlands, the UK, Sweden and Spain and marginal in other countries studied.

CONCLUSIONS

This study highlights the value of comparative cohort analysis to better understand the relationship between maternal education and markers of fetal growth in different settings across Europe.

Effects of Antenatal Maternal Depression and Anxiety on Children's Early Cognitive Development: A Prospective Cohort Study

Introduction

Studies have shown that depression or anxiety occur in 10–20% of pregnant women. These disorders are often undertreated and may affect mothers and children’s health. This study investigates the relation between antenatal maternal depression, anxiety and children’s early cognitive development among 1380 two-year-old children and 1227 three-year-old children.

Methods

In the French EDEN Mother-Child Cohort Study, language ability was assessed with the Communicative Development Inventory at 2 years of age and overall development with the Ages and Stages Questionnaire at 3 years of age. Multiple regressions and structural equation modeling were used to examine links between depression, anxiety during pregnancy and child cognitive development.

Results

We found strong significant associations between maternal antenatal anxiety and poorer children’s cognitive development at 2 and 3 years. Antenatal maternal depression was not associated with child development, except when antenatal maternal anxiety was also present. Both postnatal maternal depression and parental stimulation appeared to play mediating roles in the relation between antenatal maternal anxiety and children’s cognitive development. At 3 years, parental stimulation mediated 13.2% of the effect of antenatal maternal anxiety while postnatal maternal depression mediated 26.5%.

Discussion

The partial nature of these effects suggests that other mediators may play a role. Implications for theory and research on child development are discussed.

Predictors of persistent maternal depression trajectories in early childhood: results from the EDEN mother-child cohort study in France

BACKGROUND

Maternal depression in the pre- and postpartum period may set women on a course of chronic depressive symptoms. Little is known about predictors of persistently elevated depressive symptoms in mothers from pregnancy onwards. The aims of this study are to determine maternal depression trajectories from pregnancy to the child's fifth birthday and identify associated risk factors.

METHOD

Mothers (N = 1807) from the EDEN mother-child birth cohort study based in France (2003-2011) were followed from 24-28 weeks of pregnancy to their child's fifth birthday. Maternal depression trajectories were determined with a semi-parametric group-based modelling strategy. Sociodemographic, psychosocial and psychiatric predictors were explored for their association with trajectory class membership.

RESULTS

Five trajectories of maternal symptoms of depression from pregnancy onwards were identified: no symptoms (60.2%); persistent intermediate-level depressive symptoms (25.2%); persistent high depressive symptoms (5.0%); high symptoms in pregnancy only (4.7%); high symptoms in the child's preschool period only (4.9%). Socio-demographic predictors associated with persistent depression were non-French origin; psychosocial predictors were childhood adversities, life events during pregnancy and work overinvestment; psychiatric predictors were previous mental health problems, psychological help, and high anxiety during pregnancy.

CONCLUSIONS

Persistent depression in mothers of young children is associated to several risk factors present prior to or during pregnancy, notably anxiety. These characteristics precede depression trajectories and offer a possible entry point to enhance mother's mental health and reduce its burden on children.

Maternal Depression Trajectories and Children's Behavior at Age 5 Years

OBJECTIVE

To assess the relationship between trajectories of maternal depression from pregnancy to the child's age of 5 years and children's emotional and behavioral difficulties at age 5 years.

STUDY DESIGN

Mother-child pairs (n = 1183) from the EDEN mother-child birth cohort study based in France were followed from 24 to 28 weeks of pregnancy to the child's fifth birthday. Children's behavior at age 5 years was assessed with the Strengths and Difficulties Questionnaire. Maternal depression was assessed repeatedly with the Center for Epidemiological Studies Depression questionnaire (pregnancy, 3, and 5 years of age) and the Edinburgh Postnatal Depression Scale (4, 8, and 12 months postpartum). Homogeneous latent trajectory groups of maternal depression were identified within the study population and correlated with Strengths and Difficulties Questionnaire scores by the use of multivariate linear regression analyzes.

RESULTS

Five trajectories of maternal symptoms of depression were identified: no symptoms (62.0%); persistent intermediate-level depressive symptoms (25.3%); persistent high depressive symptoms (4.6%); high symptoms in pregnancy only (3.6%); and high symptoms in the child's preschool period only (4.6%). Children whose mothers had persistent depressive symptoms--either intermediate or high--had the greatest levels of emotional and behavioral difficulties at age 5 years. In addition, compared with children whose mothers were never depressed, those whose mothers had high symptoms in the preschool period also had increased levels of emotional symptoms, conduct problems, and peer problems.

CONCLUSIONS

Maternal depression symptoms are related to children's emotional and behavioral problems, particularly if they are persistent (29.9%) or occur during early childhood (4.6%).

The association between linoleic acid levels in colostrum and child cognition at 2 and 3 y in the EDEN cohort

BACKGROUND

Breastfeeding has been associated with improved cognitive development. This may be explained by polyunsaturated fatty acid (PUFA) content of breast milk, especially long-chain (LC) PUFA that are needed for postnatal brain growth.

METHODS

Using data from the French EDEN cohort, we aimed to study whether the PUFA content of colostrum may explain observed associations between breastfeeding duration and cognitive scores at 2 and 3 y. A total of 709 breastfed children with available data on PUFA composition of milk were assessed using parent-reported questionnaires for motor and language at 2 y of age, or global cognition at 3 y. Multiple linear regressions were used to examine associations between PUFA levels and child cognitive scores, after controlling for many confounders.

RESULTS

We found no association between LCPUFA levels in colostrum and child development. However, levels of linoleic acid (LA) were negatively associated with motor and cognitive scores, independently of breastfeeding duration. Children breastfed with the highest levels of LA tended to score closer to the never breastfed children than children breastfed with the lowest levels of LA.

CONCLUSION

Our findings suggest that too high levels of LA in colostrum are associated with poorer child development at 2 and 3 y.

Effects of polyunsaturated fatty acid intake and status during pregnancy, lactation, and early childhood on cardiometabolic health: A systematic review

The importance of polyunsaturated fatty acid (PUFA) intake in fetal life and infancy has been widely studied in relation to child cognitive and visual development, but whether early life PUFA exposure is related to cardiometabolic risk factors is unclear. The focus of this systematic review was to evaluate the effects of PUFA dietary intake and blood levels during pregnancy, lactation, or early childhood (⩽5 y) on obesity, blood pressure, blood lipids, and insulin sensitivity. We identified 4302 abstracts in the databases Embase, Medline and Cochrane Central (April 2014), of which 56 articles, reporting on 45 unique studies, met all selection criteria. Many of the included studies focused on obesity as an outcome (33 studies), whereas studies on insulin sensitivity were relatively scarce (6 studies). Overall, results for obesity, blood pressure, and blood lipids were inconsistent, with a few studies reporting effects in opposite directions and other studies that did not observe any effects of PUFAs on these outcomes. Four studies suggested beneficial effects of PUFAs on insulin sensitivity. We conclude that there is insufficient evidence to support a beneficial effect of PUFAs in fetal life or early childhood on obesity, blood pressure, or blood lipids. More research is needed to investigate the potential favorable effects of PUFAs on insulin sensitivity, and to examine the role of specific fatty acids in early life on later cardiometabolic health.

Social withdrawal at 1 year is associated with emotional and behavioural problems at 3 and 5 years: the Eden mother-child cohort study

The objective of the study was to examine how social withdrawal in infants aged 12 months predicted emotional and behavioural problems at ages 3 and 5 years. The sample included 1,586 infants from the French Eden Mother-Child Cohort Study who had a measure of social withdrawal with the Alarm Distress BaBy scale at age 1 year; among these children, emotional and behavioural difficulties were rated by mothers using the Strength and Difficulty Questionnaire (SDQ) at 3 years for 1,257 (79 %) children and at 5 years for 1,123 (72 %) children. Social withdrawal behaviour at age 1 year was significantly associated with the SDQ behavioural disorder scale at 3 years, independently of a host of familial and child temperament confounders. The association with the relational disorder, prosocial and total difficulty scales was close to significance at 3 years after taking into account familial and temperament confounders. Social withdrawal significantly predicted the three aforementioned scales when measured at 5 years. No significant predictivity of the emotional scale and hyperactivity scale was detected at any age. This study made with a large longitudinal sample confirms the negative effects on development of social withdrawal behaviour, shedding light on the unfolding of behavioural disorders and relational difficulties in children; this calls for early detection of sustained social withdrawal behaviour, as it seems to hamper emotional development.

Returning to work one year after childbirth: data from the mother-child cohort EDEN

The amount of time women spend out of work postpartum has implications for both health and economic trajectories which may result in long-term social inequities or exacerbate those already existing. The purpose of this investigation was to describe the characteristics of women who return to work within the first year postpartum and to identify specific occupational and health factors associated with returning to work among women who worked during pregnancy. The EDEN cohort is comprised of pregnant women recruited in two French university hospitals before 24 weeks gestation with a singleton pregnancy. Questionnaires were administered at 4, 8, and 12 months after birth. Multivariate logistic regression was used to model the odds of returning to work within 1 year of childbirth with inclusion of sociodemographic, health, and occupational variables that were significantly related to returning to work at the level of p < 0.05 in bivariate analysis. Eighty percent of the women who worked during pregnancy in our sample had resumed work before their infant's first birthday. After adjustment, occupational level, full-time work, standing position, job reward, desire to change job, education, and father's occupational level remained significantly associated with returning to work. Women's perception of their work as rewarding was the strongest predictor of resuming employment (OR comparing high reward to low reward: 2.48, 95 % CI: 1.60-3.83 for women with parity 0 or 1). Experiencing an adverse birth outcome had no relation to returning to work within 1 year postpartum. Across all indicator variables, women of higher socioeconomic status or with greater resources had greater odds of returning to work compared to those of lower status. This suggests that the crucial period of employment transition around the time of childbirth may intensify preexisting social inequalities.

Predicting changes in language skills between 2 and 3 years in the EDEN mother-child cohort

Objective. To examine the factors predicting changes in language skills between 2 and 3 years. Methods. By using longitudinal data concerning 1002 children from the EDEN study, linear regression was used to predict 3-year language performance from 2-year language performance and the risk factors associated with language delays. Logistic regressions were performed to examine two change trajectories: children who fall below the 10th percentile of language skills between 2 and 3 years (declining trajectory), and those who rose above the 10th percentile (resilient trajectory). Results. The final linear model accounted for 43% of the variance in 3-year language scores, with 2-year language scores accounting for 22%. Exposure to alcohol during pregnancy, earlier birth term, lower level of parental education and lower frequency of maternal stimulation were associated with the declining trajectory. Breastfeeding was associated with the resilient trajectory. Conclusions. This study provides a better understanding of the natural history of early language delays by identifying biological and social factors that predict changes in language skills between the ages of 2 and 3 years.

Fish intake during pregnancy, fetal growth, and gestational length in 19 European birth cohort studies

BACKGROUND

Fish is a rich source of essential nutrients for fetal development, but in contrast, it is also a well-known route of exposure to environmental pollutants.

OBJECTIVE

We assessed whether fish intake during pregnancy is associated with fetal growth and the length of gestation in a panel of European birth cohort studies.

DESIGN

The study sample of 151,880 mother-child pairs was derived from 19 population-based European birth cohort studies. Individual data from cohorts were pooled and harmonized. Adjusted cohort-specific effect estimates were combined by using a random- and fixed-effects meta-analysis.

RESULTS

Women who ate fish >1 time/wk during pregnancy had lower risk of preterm birth than did women who rarely ate fish (≤ 1 time/wk); the adjusted RR of fish intake >1 but <3 times/wk was 0.87 (95% CI: 0.82, 0.92), and for intake ≥ 3 times/wk, the adjusted RR was 0.89 (95% CI: 0.84, 0.96). Women with a higher intake of fish during pregnancy gave birth to neonates with a higher birth weight by 8.9 g (95% CI: 3.3, 14.6 g) for >1 but <3 times/wk and 15.2 g (95% CI: 8.9, 21.5 g) for ≥ 3 times/wk independent of gestational age. The association was greater in smokers and in overweight or obese women. Findings were consistent across cohorts.

CONCLUSION

This large, international study indicates that moderate fish intake during pregnancy is associated with lower risk of preterm birth and a small but significant increase in birth weight.

Breastfeeding duration, social and occupational characteristics of mothers in the French 'EDEN mother-child' cohort

Socio-demographic characteristics of mothers have been associated with exclusive breastfeeding duration, but little is known about the association with maternal full- and part-time employment and return to work in European countries. To study the associations between breastfeeding, any and almost exclusive (infants receiving breast milk as their only milk) breastfeeding, at 4 months of infant's age and the socio-demographic and occupational characteristics of mothers. We used the EDEN mother-child cohort, a prospective study of 2002 singleton pregnant women in two French university hospitals. We selected all mothers (n = 1,339) who were breastfeeding at discharge from the maternity unit. Data on feeding practices were collected at the maternity unit and by postal questionnaires at 4, 8 and 12 months after the birth. Among infants breastfed at discharge, 93% were still receiving any breastfeeding (83% almost exclusive breastfeeding) at the 3rd completed week of life, 78% (63%) at the 1st completed month, and 42% (20%) at the 4th completed month. Time of return to work was a major predictor for stopping breastfeeding: the sooner the mothers returned to work, the less they breastfed their babies at 4 months of infant's age, independently of full-time or part-time employment. The association was stronger for almost exclusive breastfeeding mothers than for any breastfeeding ones. In a society where breastfeeding is not the norm, women may have difficulties combining work and breastfeeding. Specific actions need to be developed and assessed among mothers who return to work and among employers.

Degree of methylation of ZAC1 (PLAGL1) is associated with prenatal and post-natal growth in healthy infants of the EDEN mother child cohort

The ZAC1 gene, mapped to the 6q24 region, is part of a network of co-regulated imprinted genes involved in the control of embryonic growth. Loss of methylation at the ZAC1 differentially methylated region (DMR) is associated with transient neonatal diabetes mellitus, a developmental disorder involving growth retardation and diabetes in the first weeks of post-natal life. We assessed whether the degree of methylation of the ZAC1 DMR in leukocytes DNA extracted from cord blood is associated with fetal, birth and post-natal anthropometric measures or with C-peptide concentrations in cord serum. We also searched for an influence of dietary intake and maternal parameters on ZAC1 DMR methylation. We found positive correlations between the ZAC1 DMR methylation index (MI) and estimated fetal weight (EFW) at 32 weeks of gestation, weight at birth and weight at one year of age (respectively, r = 0.15, 0.09, 0.14; P values = 0.01, 0.15, 0.03). However, there were no significant correlations between the ZAC1 DMR MI and cord blood C-peptide levels. Maternal intakes of alcohol and of vitamins B2 were positively correlated with ZAC1 DMR methylation (respectively, r = 0.2 and 0.14; P = 0.004 and 0.04). The influence of ZAC1 seems to start in the second half of pregnancy and continue at least until the first year of life. The maternal environment also appears to contribute to the regulation of DNA methylation.

Longitudinal follow-up of the relationship between dietary intake and growth and development in the Lifeways cross-generation cohort study 2001-2013

In this paper we will review evidence on the early life and familial influences on childhood growth and development, with particular reference to the Lifeways cross-generation cohort study in the Republic of Ireland. The Lifeways cross-generation cohort study was established in 2001-2013 through two maternity hospitals in the Republic of Ireland and was one of many new cohort studies established worldwide in the millennium period. Mothers were recruited at first booking visit, completing a self-administered questionnaire, which included a 147 item semi-quantitative FFQ. Longitudinal follow-up is ongoing in 2013, with linkage data to hospital and general practice records and examination of children when aged 5 and 9 years. The study is one of very few containing data on grandparents of both lineages with at least one grandparent recruited at baseline. There have been consistent associations between parental and grandparental health status characteristics and children's outcomes, including infant birth-weight, BMI when child was aged 5 years and childhood wheeze or asthma when child was aged 3 and aged 5 years. In conclusion, empirical evidence to date shows consistent familial and cross-generational patterns, particularly in the maternal line.

Does consideration of larger study areas yield more accurate estimates of air pollution health effects? An illustration of the bias-variance trade-off in air pollution epidemiology

BACKGROUND

Spatially-resolved air pollution models can be developed in large areas. The resulting increased exposure contrasts and population size offer opportunities to better characterize the effect of atmospheric pollutants on respiratory health. However the heterogeneity of these areas may also enhance the potential for confounding. We aimed to discuss some analytical approaches to handle this trade-off.

METHODS

We modeled NO2 and PM10 concentrations at the home addresses of 1082 pregnant mothers from EDEN cohort living in and around urban areas, using ADMS dispersion model. Simulations were performed to identify the best strategy to limit confounding by unmeasured factors varying with area type. We examined the relation between modeled concentrations and respiratory health in infants using regression models with and without adjustment or interaction terms with area type.

RESULTS

Simulations indicated that adjustment for area limited the bias due to unmeasured confounders varying with area at the costs of a slight decrease in statistical power. In our cohort, rural and urban areas differed for air pollution levels and for many factors associated with respiratory health and exposure. Area tended to modify effect measures of air pollution on respiratory health.

CONCLUSIONS

Increasing the size of the study area also increases the potential for residual confounding. Our simulations suggest that adjusting for type of area is a good option to limit residual confounding due to area-associated factors without restricting the area size. Other statistical approaches developed in the field of spatial epidemiology are an alternative to control for poorly-measured spatially-varying confounders.

The dietary n6:n3 fatty acid ratio during pregnancy is inversely associated with child neurodevelopment in the EDEN mother-child cohort

Long-chain polyunsaturated fatty acids (LC-PUFAs) of the n6 (ω6) and n3 series are essential for the development of a child's brain. Fetal LC-PUFA exposure as well as infant exposure via breast milk depend on the maternal intake of these LC-PUFAs and of their respective dietary precursors (PUFAs). We aimed to investigate the associations between maternal LC-PUFA and PUFA [(LC)PUFA] dietary intake during pregnancy and child neurodevelopment at ages 2 and 3 y. In 1335 mother-child pairs from the EDEN cohort, we evaluated associations between daily maternal (LC)PUFA intake during the last 3 months of pregnancy with the child's language at age 2 y and with different assessments of development at age 3 y. Associations were investigated separately in breastfed and never-breastfed children. We examined interactions between the ratios of n6 and n3 (LC)PUFA intakes (n6:n3 fatty acid ratio) and duration of breastfeeding. Breastfeeding mothers had a lower n6:n3 fatty acid ratio (8.4 vs. 8.8; P = 0.02). Among never-breastfed children (n = 338), we found negative associations between maternal dietary n6:n3 fatty acid ratios and neurodevelopment, as reflected by the child's language at age 2 y (β ± SE = -2.1 ± 0.7; P = 0.001) and development assessed with the Ages and Stages Questionnaire at age 3 y (-1.5 ± 0.8; P = 0.05). Among mothers with a high n6:n3 fatty acid ratio only, breastfeeding duration was positively associated with language at age 2 y (P-interaction < 0.05). This suggests that the ratio between maternal dietary n6 and n3 (LC)PUFA intake possibly influences the child's brain development during fetal life but not during or by breastfeeding. However, breastfeeding might compensate for prenatal imbalance in maternal dietary n6:n3 fatty acid ratio.

Exposure to food contaminants during pregnancy

During pregnancy, the fetus is exposed to contaminants from its mother's diet. This work provides an assessment of the dietary exposure of pregnant women to inorganic contaminants (aluminum, mercury, lead, inorganic arsenic, cobalt), polychlorodibenzodioxins, polychlorodibenzofurans, dioxin-like and non-dioxin-like polychlorobiphenyls (DL-PCBs, NDL-PCBs), polybromodiphenyl ethers (PBDEs), perfluoroalkyl acids, mycotoxins (zearalenone, patulin, trichothecenes), and heat-generated compounds (acrylamide and polycyclic aromatic hydrocarbons). Consumption data of 2002 pregnant women aged 18 to 45 from the EDEN cohort study were combined with contamination data from the second French total diet study to assess the exposure before pregnancy (n=1861) and during the third trimester of pregnancy (n=1775). Exposure was also assessed considering the season during which the third trimester of pregnancy occurred. Significant changes in consumptions during pregnancy and between seasons were associated with differences in exposures for some substances. Some contaminant exposures appeared to be of health concern. Margins of exposure to acrylamide (635 to 1094 for mean), inorganic arsenic, lead, and BDE-99 (≤100) were too low to exclude all risks. For NDL-PCBs, T-2 and HT-2 toxins, and deoxynivalenol, significant exceedings of toxicological reference values were found before pregnancy, but there was no significant exceeding in the third trimester.

Pregnancy and birth cohort resources in europe: a large opportunity for aetiological child health research

BACKGROUND

During the past 25 years, many pregnancy and birth cohorts have been established. Each cohort provides unique opportunities for examining associations of early-life exposures with child development and health. However, to fully exploit the large amount of available resources and to facilitate cross-cohort collaboration, it is necessary to have accessible information on each cohort and its individual characteristics. The aim of this work was to provide an overview of European pregnancy and birth cohorts registered in a freely accessible database located at http://www.birthcohorts.net.

METHODS

European pregnancy and birth cohorts initiated in 1980 or later with at least 300 mother-child pairs enrolled during pregnancy or at birth, and with postnatal data, were eligible for inclusion. Eligible cohorts were invited to provide information on the data and biological samples collected, as well as the timing of data collection.

RESULTS

In total, 70 cohorts were identified. Of these, 56 fulfilled the inclusion criteria encompassing a total of more than 500,000 live-born European children. The cohorts represented 19 countries with the majority of cohorts located in Northern and Western Europe. Some cohorts were general with multiple aims, whilst others focused on specific health or exposure-related research questions.

CONCLUSION

This work demonstrates a great potential for cross-cohort collaboration addressing important aspects of child health. The web site, http://www.birthcohorts.net, proved to be a useful tool for accessing information on European pregnancy and birth cohorts and their characteristics.

Breastfeeding duration and cognitive development at 2 and 3 years of age in the EDEN mother-child cohort

OBJECTIVE

To investigate the dose-response relationship between breastfeeding duration and cognitive development in French preschool children.

STUDY DESIGN

In the French EDEN Mother-Child Cohort Study, we evaluated language ability with the Communicative Development Inventory (CDI) in 1387 2-year-old children and overall development with the Ages and Stages Questionnaire (ASQ) in 1199 3-year-old children. Assessments were compared between breastfed and non-breastfed children and also according to breastfeeding duration in multivariable linear models, controlling for a wide range of potential confounders. We tested departure from linearity.

RESULTS

After adjustments, ever-breastfed children scored 3.7 ± 1.8 (P = .038) points higher than never-breastfed children on the CDI and 6.2 ± 1.9 (P = .001) points higher on the ASQ. Among breastfed children, exclusive and any-breastfeeding durations were positively associated with both CDI and ASQ scores. The fine motor domain of ASQ was associated with any-breastfeeding duration, and the problem solving domain with exclusive-breastfeeding duration. We did not observe significant departures from linearity. No interactions were found between the child's sex, parental education or socioeconomic status, and breastfeeding duration.

CONCLUSION

Longer breastfeeding duration was associated with better cognitive and motor development in 2- and 3-year-old children and a dose-response relationship was suggested.

Depression and anxiety in women during pregnancy and neonatal outcome: data from the EDEN mother-child cohort

BACKGROUND

According to the World Health Organization, mental health disorders are the leading causes of disease burden in women from 15 to 44 years. These conditions in pregnant women may affect the offspring.

AIM

To analyze the relation between depression and anxiety of pregnant women and neonatal outcomes including gestational age and birthweight.

STUDY DESIGN

Observational cohort study.

SUBJECTS

2002 women recruited before the 20th gestational week.

OUTCOME MEASURES

Gestational age at delivery in completed weeks of amenorrhea and preterm delivery defined as birth before 37 completed weeks of gestation. Spontaneous preterm birth (PB) defined as either spontaneous preterm labor or preterm premature rupture of the membranes. Medically indicated preterm delivery defined as delivery that begins by induction or cesarean section. Birthweight as a continuous variable and centiles of the customized fetal weight norms for the French population.

RESULTS

From the 1719 women included in the study, 7.9% (n=135) were classified as "anxious", 11.8% (n=203) as "depressed", 13.2% (n=227) as "depressed and anxious". After adjusting for potential confounders, depression combined with anxiety during pregnancy increased the risk of spontaneous PB (Odds Ratio: 2.46 [1.22-4.94]), but did not influence medically indicated PB nor birthweight.

CONCLUSION

In this study, comorbidity of depressive and anxiety symptoms was the worst condition during pregnancy. Further studies are needed to investigate depression and anxiety together to improve the comprehension of the biological modifications involved.

Systematic review and meta-analysis of energy and macronutrient intakes during pregnancy in developed countries

Research reporting diet during pregnancy in nationally representative samples is limited. This review summarizes the dietary intakes of pregnant women in developed countries and compares them with national recommendations. A systematic search without date limits was conducted. All studies reporting the macronutrient intakes of pregnant women were considered, irrespective of design. Two authors independently identified the studies to be included and assessed the methodological quality. Nutritional adequacy was summarized, with confounding factors considered. Meta-analysis data are reported for developed countries collectively, by geographical region, and by dietary methodology. Energy and macronutrient intakes of pregnant women do not match national recommendations. Energy and fiber intakes were consistently below recommendations, while total fat and saturated fat intakes were generally above recommendations and carbohydrate and polyunsaturated fat intakes were below to borderline low compared with recommendations. A mismatch between dietary practices and macronutrient recommendations in pregnant women is widespread and not well quantified. The implications of these practices are unknown until further research compares maternal diet with short-term and long-term maternal and offspring health outcomes.

Specific role of maternal weight change in the first trimester of pregnancy on birth size

The specific role of weight change in the first weeks of gestation in fetal growth has not been fully explored in humans. Our aims were to investigate: (1) the specific association between weight change in the first trimester of pregnancy (WCT1) and size at birth in term pregnancies; and (2) the role of placental weight in this relationship. From 2002 women included in the French EDEN study, 1744 mother-child pairs reached term, had pre-pregnancy weight available and at least five measures of weight in pregnancy. We extrapolated women's weight at each week of gestation with a three-degree polynomial model and estimated weight change during each trimester of gestation. We used a multivariate linear model to investigate the associations between WCT1 and birth size after taking into account potential confounders (age, parity, BMI, tobacco use, educational level, length of gestation, newborn gender, weight change after the first trimester and centre of study). Then, we performed path analysis to investigate whether the relation between WCT1 and birth size could be mediated by placental weight. After taking into account weight gain in later gestation, WCT1 was positively associated with birthweight. Results of path analysis showed that there was no direct association between WCT1 and birth size, but that this association was mediated by placental weight. Weight change during the first weeks of pregnancy may impact on fetal growth independently of weight change later in pregnancy through its effects on placental growth and function.

Perinatal risk factors and social withdrawal behaviour

The objectives of the study were (1) to assess prevalence of social withdrawal behaviour in infants aged 12 months included in the French Perinatal Risk Factor Study Eden; (2) To study the correlation between relational withdrawal and several perinatal and parental factors assessed in the EDEN study. A longitudinal study using the ADBB scale was conducted within the Eden Cohort in the year 2008. 1,586 infants were included in the study. Fourteen percent of the children who had an ADBB assessment had a score at 5 and over on the ADBB, a scale designed to assess social withdrawal behaviour at age 0-24 months. Social withdrawal at 12 months was associated with low birth weight, low gestational age and with intra uterine growth retardation. Social withdrawal was independently associated with several maternal and paternal risk factors. The level of social withdrawal behaviour increased with a score of maternal difficulties. This study on a large longitudinally followed volunteer sample demonstrate a clear association of social withdrawal behaviour at age one with low birth weight and preterm birth, possibly mediated by parental vulnerabilities. Social withdrawal behaviour seems to be an important alarm signal to detect early on particularly in premature and small for date babies.

Exposure to phthalates and phenols during pregnancy and offspring size at birth

BACKGROUND

Data concerning the effects of prenatal exposures to phthalates and phenols on fetal growth are limited in humans. Previous findings suggest possible effects of some phenols on male birth weight.

OBJECTIVE

Our aim was to assess the relationships between prenatal exposures to phthalates and phenols and fetal growth among male newborns.

METHODS

We conducted a case-control study on male malformations of the genitalia nested in two French mother-child cohorts with recruitment between 2002 and 2006. We measured, in maternal urinary samples collected between 6 and 30 gestational weeks, the concentrations (micrograms per liter) of 9 phenol (n = 191 pregnant women) and 11 phthalate metabolites (n = 287). Weight, length, and head circumference at birth were collected from maternity records. Statistical analyses were corrected for the oversampling of malformation cases.

RESULTS

Adjusted birth weight decreased by 77 g [95% confidence interval (CI): -129, -25] and by 49 g (95% CI: -86, -13) in association with a 1-unit increase in ln-transformed 2,4-dichlorophenol (DCP) and 2,5-DCP urinary concentrations, respectively. Benzophenone-3 (BP3) ln-transformed concentrations were positively associated with weight (26 g; 95% CI: -2, 54) and head circumference at birth (0.1 cm; 95% CI: 0.0, 0.2). Head circumference increased by 0.3 cm (95% CI: 0.0, 0.7) in association with a 1-unit increase in ln-transformed BPA concentration. For phthalate metabolites there was no evidence of monotonic associations with birth weight.

CONCLUSIONS

Consistent with findings of a previous study, we observed evidence of an inverse association of 2,5-DCP and a positive association of BP3 with male birth weight.

Maternal weight change before pregnancy in relation to birthweight and risks of adverse pregnancy outcomes

Maternal weight change before pregnancy can be considered as an indicator of maternal energy balance and nutritional status before conception, and may be involved in early life programming. We aimed to investigate the association of maternal Weight Change Before Pregnancy (WCBP) with fetal growth and adverse pregnancy outcomes. Data are from the French EDEN mother-child cohort where 1,756 mother-child pairs had information on mother's weight at 20 years, weight just before pregnancy, fetal anthropometry at second and third trimesters, infant's birthweight and pregnancy complications. The average annual WCBP between 20 years and start of pregnancy (in kg/year) was categorized as: "Weight Loss" (n = 320), "Moderate weight gain" (n = 721) and "High weight gain" (n = 715). The associations of WCBP with fetal and newborn characteristics and with adverse pregnancy outcomes were analyzed, adjusting for maternal and pregnancy characteristics, including the mother's prepregnancy BMI. Interactions between WCBP and prepregnancy BMI were tested. Birthweight and estimated fetal weight in the third trimester increased significantly with increasing WCBP in mothers with BMI <25 kg/m(2). In these mothers, weight loss before pregnancy was associated with a higher risk of newborns small for gestational age (SGA). Whatever the prepregnancy BMI, WCBP was positively associated with a maternal risk of gestational diabetes and hypertension. The ponderal history of mothers before pregnancy can impact on fetal growth and on pregnancy outcomes such as gestational diabetes or hypertension. Our analysis is the first to report that in non-overweight women, those who lost weight before pregnancy are at higher risk of having SGA newborns.

Maternal exposure to nitrogen dioxide during pregnancy and offspring birth weight: comparison of two exposure models

BACKGROUND

Studies of the effects of air pollutants on birth weight often assess exposure with networks of permanent air quality monitoring stations (AQMSs), which have a poor spatial resolution.

OBJECTIVE

We aimed to compare the exposure model based on the nearest AQMS and a temporally adjusted geostatistical (TAG) model with a finer spatial resolution, for use in pregnancy studies.

METHODS

The AQMS and TAG exposure models were implemented in two areas surrounding medium-size cities in which 776 pregnant women were followed as part of the EDEN mother-child cohort. The exposure models were compared in terms of estimated nitrogen dioxide (NO2) levels and of their association with birth weight.

RESULTS

The correlations between the two estimates of exposure during the first trimester of pregnancy were r = 0.67, 0.70, and 0.83 for women living within 5, 2, and 1 km of an AQMS, respectively. Exposure patterns displayed greater spatial than temporal variations. Exposure during the first trimester of pregnancy was most strongly associated with birth weight for women living < 2 km away from an AQMS: a 10-µg/m3 increase in NO2 exposure was associated with an adjusted difference in birth weight of -37 g [95% confidence interval (CI), -75 to 1 g] for the nearest-AQMS model and of -51 g (95% CI, -128 to 26 g) for the TAG model. The association was less strong (higher p-value) for women living within 5 or 1 km of an AQMS.

CONCLUSIONS

The two exposure models tended to give consistent results in terms of association with birth weight, despite the moderate concordance between exposure estimates.

Determinants of early ponderal and statural growth in full-term infants in the EDEN mother-child cohort study

BACKGROUND

Growth velocity in the first months of postnatal life has been associated with later overweight and obesity.

OBJECTIVE

We analyzed prenatal and postnatal factors in association with weight, length, and growth velocities in the first 3 mo of life.

DESIGN

We estimated weight, length, and instantaneous weight- and length-growth velocities (in g/d and mm/d) in 1418 term infants at 1 and 3 mo of age and evaluated the following potential determinants: maternal prepregnancy body mass index (BMI), 1-h plasma glucose concentrations during pregnancy, smoking, socioeconomic status, parity, paternal BMI, parental heights, and infant feeding, gestational age, and sex.

RESULTS

Maternal obesity and plasma glucose concentrations were associated with the weights and lengths of offspring at birth but not at 1 and 3 mo after birth. In contrast, there was no association between paternal BMI and anthropometric measures of offspring at birth, but by 3 mo of age infants of obese fathers had significantly higher weights and weight-growth velocities than did infants of fathers with a normal BMI. Maternal weight gain was a significant predictor of weight at birth and 3 mo of age. Exclusively breastfed infants had a slower weight-growth velocity as early as 1 mo of age compared with exclusively formula-fed infants.

CONCLUSIONS

In the first 3 mo of life, the positive associations between maternal obesity, plasma glucose concentrations, and infant anthropometric measures at birth seem to progressively fade away, whereas the emerging association with paternal BMI may indicate an early postnatal influence of paternal genetics. Among the determinants we evaluated, some are potentially modifiable, such as maternal gestational weight gain and infant feeding. The identification of optimal patterns of growth remains crucial before providing any clinical recommendations.