A maternal dietary pattern characterised by fish and seafood in association with the risk of congenital heart defects in the offspring

Understanding the Genetic and Non-genetic Interconnections in the Aetiology of Isolated Congenital Heart Disease: An Updated Review: Part 1

PURPOSE OF REVIEW

Congenital heart disease (CHD) is the most frequently occurring birth defect. Majority of the earlier reviews focussed on the association of genetic factors with CHD. A few epidemiological studies provide convincing evidence for environmental factors in the causation of CHD. Although the multifactorial theory of gene-environment interaction is the prevailing explanation, explicit understanding of the biological mechanism(s) involved, remains obscure. Nonetheless, integration of all the information into one platform would enable us to better understand the collective risk implicated in CHD development.

RECENT FINDINGS

Great strides in novel genomic technologies namely, massive parallel sequencing, whole exome sequencing, multiomics studies supported by system-biology have greatly improved our understanding of the aetiology of CHD. Molecular genetic studies reveal that cardiac specific gene variants in transcription factors or signalling molecules, or structural proteins could cause CHD. Additionally, non-hereditary contributors such as exposure to teratogens, maternal nutrition, parental age and lifestyle factors also contribute to induce CHD. Moreover, DNA methylation and non-coding RNA are also correlated with CHD. Here, we inform that a complex combination of genetic, environmental and epigenetic factors interact to interfere with morphogenetic processes of cardiac development leading to CHD. It is important, not only to identify individual genetic and non-inherited risk factors but also to recognize which factors interact mutually, causing cardiac defects.

Dietary Inflammatory Index during Pregnancy and Congenital Heart Defects

The relationship between diet-related inflammation during pregnancy and congenital heart defects (CHD) is unclear. This study attempted to investigate the association between the dietary inflammation index (DII) during pregnancy, reflecting the overall inflammatory potential of the maternal diet, and CHD in Northwest China. A case-control study with 474 cases and 948 controls was performed in Xi'an City, China. Eligible women awaiting delivery were recruited, and their dietary and other information during pregnancy was collected. Logistic regression models were applied to estimate the risk of CHD in association with DII. The maternal DII ranged from -1.36 to 5.73 in cases, and 0.43 to 5.63 in controls. Pregnant women with per 1 higher DII score were at 31% higher risk of fetal CHD (OR = 1.31, 95%CI = 1.14-1.51), and the adjusted OR (95%CI) comparing the pro-inflammatory diet group with the anti-inflammatory diet group was 2.04 (1.42-2.92). The inverse association of maternal DII score with CHD risk was consistent across various subgroups of maternal characteristics. Maternal DII in pregnancy had good predictive value for CHD in offspring, with the areas under the receiver operating characteristic curve higher than 0.7. These findings suggested that avoiding a pro-inflammatory diet in pregnancy should be emphasized in the prevention of CHD.

Maternal Dietary Inflammatory Potential and Offspring Birth Outcomes in a Chinese Population

BACKGROUND

Chronic inflammation perturbations during pregnancy may impact fetal growth; however, research on the association between dietary inflammation and birth outcomes is limited and inconsistent.

OBJECTIVES

This study seeks to assess whether the dietary inflammatory potential is related to birth outcomes among pregnant women in China.

METHODS

A total of 7194 mothers aged 17-46 y and their infants in China were included in this cross-sectional study. Dietary intake was assessed by a FFQ, which yielded scores on the energy-adjusted dietary inflammatory index (E-DII). Birth outcomes included birth weight, gestational age, birth weight z score, low birth weight (LBW), macrosomia, preterm birth, small-for-gestational-age (SGA), large-for-gestational-age (LGA), and birth defects. Generalized estimating equation and restricted cubic spline fit each outcome on continuous or quartiles of E-DII after adjusting for covariates.

RESULTS

The maternal E-DII ranged from -5.35 to 6.77. Overall, birth weight and gestation age (mean ± SD) were 3267.9 ± 446.7 g and 39.6 ± 1.3 wk, respectively, and the birth weight z score was 0.02 ± 1.14. A total of 3.2% of infants were born with LBW, 6.1% with macrosomia, 3.0% were preterm birth, 10.7% were born SGA, 10.0% were born LGA, and 2.0% were born with birth defects. E-DII was associated with a 9.8 g decrease in birth weight (95% CI: -16.9, -2.6) and a 1.09-fold (95% CI: 1.01, 1.18), 1.11-fold (95% CI: 1.02, 1.21), and 1.12-fold (95% CI: 1.02, 1.24) greater risk of LBW, preterm birth, and birth defects, respectively. The maternal E-DII score was nonlinearly associated with gestational age (P for linearity = 0.009, P for curvature = 0.044).

CONCLUSIONS

Among pregnant Chinese women, proinflammatory diets during pregnancy were related to reduced offspring birth weight and an increased risk of LBW, preterm birth, and birth defects. These findings might inform potential prevention strategies for pregnant women in China.

Dietary Quality during Pregnancy and Congenital Heart Defects

Limited studies on maternal dietary quality indices and congenital heart defects (CHD) are available. This study aimed to explore the relationship between dietary quality in pregnancy and CHD among the Chinese population. A case-control study was performed in Northwest China, and 474 cases and 948 controls were included. Eligible women waiting for delivery were interviewed to recall diets and other information during pregnancy. Dietary quality was assessed by the Global Diet Quality Score (GDQS) and Mediterranean Diet Score (MDS). Logistic regression models were adopted to evaluate the associations of dietary quality scores with CHD. Pregnant women with higher scores of GDQS and MDS were at a lower risk of fetal CHD, and the adjusted ORs comparing the extreme quartiles were 0.26 (95%CI: 0.16−0.42; Ptrend < 0.001) and 0.53 (95%CI: 0.34−0.83; Ptrend = 0.007), respectively. The inverse associations of GDQS and MDS with CHD appeared to be stronger among women with lower education levels or in rural areas. Maternal GDQS and MDS had good predictive values for fetal CHD, with the areas under the receiver operating characteristic curves close to 0.8. Efforts to improve maternal dietary quality need to be strengthened to decrease the prevalence of CHD among the Chinese population.

Shorter periconception maternal telomere length and the risk of congenital cardiac outflow defects in the offspring

BACKGROUND

Congenital cardiac outflow defects (COD) are the largest group of congenital heart defects, with ventricular septal defect (VSD) as the most prevalent phenotype. Increased maternal age, excessive oxidative stress and inflammation are involved in the pathophysiology of COD and enhance telomere length (TL) shortening. We investigated the association between periconception maternal TL and the risk of having a child with COD.

METHODS

From a multicentre case-control trial, 306 case mothers of a child with COD and 424 control mothers of a child without a congenital malformation were selected. Relative TL was measured by qPCR. Multivariable logistic regression was used to compute crude and adjusted odds ratios, per standard deviation decrease, between maternal T/S ratio and COD and VSD risk. Adjustments were made for maternal age. Additional adjustments were made in a second model.

RESULTS

Shorter maternal relative TL was significantly associated with an OR of 1.29 (95% CI 1.04-1.61), p = .02, for the risk of VSD in offspring, which remained significant after an adjustment for maternal age (adjOR 1.25(95% CI 1.01-1.55), p = .04). No association between maternal TL and the risk of overall COD in offspring was observed.

CONCLUSION

Shorter maternal relative TL is associated with an approximately 1.3-OR for the risk, per SD in relative TL shortening, of VSD in the offspring. These findings need further confirmation in other studies on the predictive value of maternal TL.

Maternal periconceptional nutrition matters. A scoping review of the current literature

BACKGROUND

The importance of nutrition in reproductive health is widely acknowledged with special emphasis given to periconceptional maternal diet and its implications on embryo-fetal development, pregnancy complications, and the health of the offspring.

METHODS

Following the PRISMA guidelines, we searched for literature in PubMed, CINAHL, and WoS to gather newer information on how diet composition influences the concepts from the very early stages of pregnancy and how maternal health may be affected as well. Fifty-six studies published up to June 2020 met the inclusion criteria.

RESULTS

With its proportioned and diversified macronutrient composition, the Mediterranean Diet prevents congenital anomalies, preterm birth, hypertensive disorders, and gestational diabetes. Similar dietary patterns rich in vegetables, nuts, fish, and cereals increase the likelihood of conception and have a protective action, mediated by their antioxidant properties, against orofacial clefts, congenital heart and limb defects in the progeny. Conversely, the pro-inflammatory features of western diets, rich in processed foods and low in fruit content, diminish fertility, increase miscarriage rates, and enhance the risk of neural tube defects regardless of folate supplementation.

CONCLUSIONS

It may be concluded that within the multiple dietary options, some of them are soundly associated with beneficial effects for the mother and the newborn.Implications for practiceAn appropriate counseling must be offered to the woman of fertile age to make her aware of how periconceptional nutrition may help fulfill her reproductive expectations.

The effects of bariatric surgery on periconception maternal health: a systematic review and meta-analysis

BACKGROUND

Worldwide, the prevalence of obesity in women of reproductive age is increasing. Bariatric surgery is currently viewed as the most effective, long-term solution for this problem. Preconception bariatric surgery can reduce the prevalence of obesity-related subfertility and adverse maternal, pregnancy and birth outcomes. Maternal health during the periconception period is crucial for optimal gametogenesis and for embryonic and fetal development which also affects health in the later lives of both mother and offspring. Although preconception bariatric surgery improves several pregnancy outcomes, it can also increase the prevalence of pregnancy complications due to excessive and rapid weight loss. This can lead to iatrogenic malnutrition with vitamin deficiencies and derangements in metabolic and endocrine homeostasis. Thus, bariatric surgery can greatly influence periconception maternal health with consequences for reproduction, pregnancy and health in later life. However, its influence on periconception maternal health itself has never been reviewed systematically.

OBJECTIVE AND RATIONALE

The aim of this review was to investigate associations between bariatric surgery and determinants of periconception maternal health such as endocrine changes, fertility, vitamin status, irregular menstrual cycles, miscarriages and congenital malformations.

SEARCH METHODS

Medline, Embase, PubMed, Web of Science, Google Scholar and the Cochrane databases were used for the literature search until 1 November 2020. The search strategy terms included, among others, bariatric surgery, hormones, fertility, malformations, miscarriages and vitamin status. We searched for human studies that were written in English. Abstracts, reviews, meta-analyses and conference papers were excluded. The ErasmusAGE score was used to assess the quality of the included studies.

OUTCOMES

A total of 51 articles were analysed. The mean quality score was 5 (range 2-8). After bariatric surgery, hormonal axes normalized and menstrual cycle regularity was restored, resulting in increased fertility. Overall, there were no short-term risks for reproductive outcomes such as the increased risk of miscarriages or congenital malformations. However, the risk of vitamin deficiencies was generally increased after bariatric surgery. A meta-analysis of 20 studies showed a significant decrease in infertility (risk difference (RD) -0.24, 95% confidence interval (CI) -0.42, -0.05) and menstrual cycle irregularities (RD -0.24, 95% CI -0.34, -0.15) with no difference in rates of miscarriage (RD 0.00, 95% CI -0.09, 0.10) and congenital malformations (RD 0.01, 95% CI -0.02, 0.03).

WIDER IMPLICATIONS

The current systematic review and meta-analysis show associations between bariatric surgery and periconception maternal health and underlines the need for providing and personalizing preconception care for women after bariatric surgery. We recommend preconception care including the recommendation of postponing pregnancy until weight loss has stabilized, irrespective of the surgery-to-pregnancy interval, and until vitamin status is normalized. Therefore, regular monitoring of vitamin status and vitamin supplementation to restore deficiencies is recommended. Furthermore, this systematic review emphasizes the need for a long-term follow-up research of these women from the periconception period onwards as well as their pregnancies and offspring, to further improve care and outcomes of these mothers and children.

Association between Neonatal Intakes and Hyperglycemia, and Left Heart and Aortic Dimensions at 6.5 Years of Age in Children Born Extremely Preterm

Survivors of extremely preterm birth (gestational age < 27 weeks) have been reported to exhibit an altered cardiovascular phenotype in childhood. The mechanisms are unknown. We investigated associations between postnatal nutritional intakes and hyperglycemia, and left heart and aortic dimensions in children born extremely preterm. Postnatal nutritional data and echocardiographic dimensions at 6.5 years of age were extracted from a sub-cohort of the Extremely Preterm Infants in Sweden Study (EXPRESS; children born extremely preterm between 2004-2007, n = 171, mean (SD) birth weight = 784 (165) grams). Associations between macronutrient intakes or number of days with hyperglycemia (blood glucose > 8 mmol/L) in the neonatal period (exposure) and left heart and aortic dimensions at follow-up (outcome) were investigated. Neonatal protein intake was not associated with the outcomes, whereas higher lipid intake was significantly associated with larger aortic root diameter (B = 0.040, p = 0.009). Higher neonatal carbohydrate intake was associated with smaller aorta annulus diameter (B = -0.016, p = 0.008). Longer exposure to neonatal hyperglycemia was associated with increased thickness of the left ventricular posterior wall (B = 0.004, p = 0.008) and interventricular septum (B = 0.004, p = 0.010). The findings in this study indicate that postnatal nutrition and hyperglycemia may play a role in some but not all long-lasting developmental adaptations of the cardiovascular system in children born extremely preterm.

Association of Maternal Dietary Habits and MTHFD1 Gene Polymorphisms With Ventricular Septal Defects in Offspring: A Case-Control Study

OBJECTIVES

This study aimed at assessing the association between maternal methylenetetrahydrofolate dehydrogenase 1 (MTHFD1) gene polymorphisms, maternal dietary habits, and their interactions with the risk of ventricular septal defects (VSD) in offspring.

METHODS

From November 2017 to March 2019, a case-control study comprising 360 mothers of VSD cases and 504 mothers of healthy infants was conducted in Han Chinese populations. The main exposures of interest were maternal dietary habits in early pregnancy and MTHFD1 gene polymorphisms. Logistic regression models were used to estimate the main effects and interaction effects.

RESULTS

It was observed that maternal excessive intake of pickled vegetables (aOR = 1.85, 95%CI: 1.45-2.37), smoked foods (aOR = 1.93, 95%CI: 1.48-2.51), barbecued foods (aOR = 1.74, 95%CI: 1.28-2.36), and fried foods (aOR = 1.68, 95%CI: 1.30-2.17) were associated with a higher risk of VSD in offspring, whereas maternal excessive intake of fresh meat (aOR = 0.61, 95%CI: 0.47-0.79), fish and shrimp (aOR = 0.29, 95%CI: 0.23-0.38), fresh eggs (aOR = 0.54, 95%CI: 0.42-0.70), fresh fruits or vegetables (aOR = 0.44, 95%CI: 0.33-0.60), soy foods (aOR = 0.65, 95%CI: 0.53-0.80), and milk products (aOR = 0.49, 95%CI: 0.40-0.59) could contribute significantly to a lower risk of VSD in offspring. Furthermore, the genetic polymorphisms of maternal MTHFD1 gene at rs1950902 (GA vs. GG: aOR = 0.67, 95%CI: 0.50-0.90) and rs2236222 (GG vs. AA: aOR = 2.75, 95%CI: 1.57-4.83) were significantly associated with the risk of VSD in offspring. In addition, there was a significant interaction effect between maternal dietary habits and MTHFD1 gene polymorphisms on the risk of VSD.

CONCLUSIONS

Maternal dietary factors, MTHFD1 genetic polymorphisms, and their interactions were all associated with the risk of VSD in offspring. However, further research in diverse ethnic populations and with a larger sample size is warranted to corroborate our findings.

TRIAL REGISTRATION

Registered in Chinese Clinical Trial Registry Center; registration number, ChiCTR1800016635; registration date, 06/14/2018 (Retrospectively registered); URL of trial registry record, https://www.chictr.org.cn/showproj.aspx?proj=28300.

Maternal dietary fat intake and the risk of congenital heart defects in offspring

BACKGROUND

Fatty acids are crucial in embryologic development, including cardiogenesis. The impact of maternal periconceptional dietary fat intake on the risk of congenital heart defects (CHDs) has not been clearly elucidated. We hypothesized that maternal dietary fat intake during pregnancy is associated with risk of CHDs in offspring.

METHODS

We analyzed CHD cases and nonmalformed controls from the National Birth Defects Prevention Study, a case-control, multicenter population-based study of birth defects. We used multivariable logistic regression to analyze the association between maternal periconceptional dietary fat intake and occurrence of CHDs.

RESULTS

We examined 11,393 infants with CHDs (cases) and 11,029 infants without birth defects (controls). Multivariable analysis of maternal dietary fat intake adjusted for maternal energy intake demonstrated modest change in risk for 2 of the 25 CHDs analyzed; otherwise there was no association. Maternal dietary fat intake unadjusted for total energy was associated with increased risk for several CHDs.

CONCLUSIONS

After adjusting for total energy intake, maternal periconceptional dietary fat intake has a modest association with risk of a few specific CHDs. If maternal dietary fat intake does impact CHD risk, the effect is minimal.

IMPACT

In this large, case-control study, after adjusting for total caloric intake, maternal periconceptional dietary fat intake was not associated with increased odds of congenital heart defects. This study investigates the hypothesis that women's periconceptional fat intake alters the risk of congenital heart defects in offspring. Our results raise questions about the role maternal fat intake may play in cardiogenesis and risk of congenital heart defects. Additionally, they raise the question about whether maternal lipid metabolism, as opposed to fat intake, may influence cardiac development.

Validation of a Semi-Quantitative Food-Frequency Questionnaire for Dutch Pregnant Women from the General Population Using the Method or Triads

OBJECTIVE

We aimed to validate a food-frequency questionnaire (FFQ) for Dutch pregnant women, against three 24 h-recalls and blood concentrations of B-vitamins and fatty acids, using the method of triads.

METHODS

We included 83 pregnant women from the general population of Rotterdam, the Netherlands, at a median gestational age of 15.6 weeks. Participants completed three non-consecutive 24 h-recalls, and subsequently filled out the 293-item FFQ. Participants provided blood samples from which we analyzed serum folate and vitamin B12, as well as red blood cell folate, linoleic acid, and total saturated, monounsaturated, and polyunsaturated fatty acids.

RESULTS

Estimated energy intake did not differ between the FFQ and 24 h-recalls. Deattenuated Pearson's correlation coefficients, between energy-adjusted nutrient intake estimates from the FFQ and the 24 h-recalls, ranged from 0.41 (fat) to 0.88 (fiber) for macronutrients, and were around 0.6 for most micronutrients, except for vitamin E (0.27). Using the triad method, we obtained validity coefficients of 0.86 (95% Confidence Interval (CI) 0.36, 1.00) for serum folate, 0.86 (95% CI 0.18, 1.00) for red blood cell folate, and 1.00 (95% CI 0.42, 1.00) for vitamin B12. Validity coefficients for serum fatty acids ranged from 0.22 to 0.67.

CONCLUSION

This FFQ is a reliable tool for estimating intake of energy, macronutrients, folate and vitamin B12 among women in mid-pregnancy.

Maternal Obesity and Diabetes Mellitus as Risk Factors for Congenital Heart Disease in the Offspring

Congenital heart disease (CHD) is the most common anatomical malformation occurring live‐born infants and an increasing cause of morbidity and mortality across the lifespan and throughout the world. Population‐based observations have long described associations between maternal cardiometabolic disorders and the risk of CHD in the offspring. Here we review the epidemiological evidence and clinical observations relating maternal obesity and diabetes mellitus to the risk of CHD offspring with particular attention to mechanistic models of maternal‐fetal risk transmission and first trimester disturbances of fetal cardiac development. A deeper understanding of maternal risk factors holds the potential to improve both prenatal detection of CHD by identifying at‐risk pregnancies, along with primary prevention of disease by improving preconception and prenatal treatment of at‐risk mothers.

Maternal dietary diversity during pregnancy and congenital heart defects: a case-control study

BACKGROUND/OBJECTIVES

Maternal diet is critical to fetal development. This study aimed to explore the association between maternal dietary diversity during pregnancy and congenital heart defects (CHD) in Chinese population.

METHODS

A hospital-based case-control study was conducted including 474 cases and 948 controls in Northwest China. We recruited eligible women waiting for delivery in the hospital and gathered their diets during the whole pregnancy by a validated food frequency questionnaire. According to the FAO Minimum Dietary Diversity for Women (MDD-W) guideline, the participants were categorized into "inadequate dietary diversity score (DDS)" (DDS < 5) and "adequate DDS" (DDS ≥ 5) groups. The association between dietary diversity and CHD was estimated using the mixed logistic regression models.

RESULTS

Case mothers had a lower DDS during pregnancy than the controls (P < 0.001). The proportions of women consuming all the ten defined food groups were lower in the inadequate DDS group than in the adequate DDS group among both cases and controls (all P < 0.001). The prevalence of inadequate micronutrient intake was higher in the inadequate DDS group than in the adequate DDS group among both cases and controls (all P < 0.05). Women in the adequate DDS group had reduced risks of having fetuses with total CHD (OR = 0.62, 95% CI = 0.45-0.84) and ventricular septal defects (OR = 0.58, 95% CI = 0.38-0.88).

CONCLUSIONS

Adequate DDS during pregnancy might be associated with a lower risk of CHD in offspring. Efforts to promote dietary diversity during pregnancy need to be strengthened to reduce the prevalence of CHD in Chinese population.

Maternal diet as a risk factor for primary congenital glaucoma and defects of the anterior segment of the eye in the National Birth Defects Prevention Study

Primary congenital glaucoma (PCG) and anterior segment defects (ASDs) are rare ocular malformations diagnosed early in life which can cause blindness. Pathogenic variants in several genes have been linked to these conditions, but little is known about nongenetic risk factors. We investigated the association between maternal nutrition and PCG and ASDs in the National Birth Defects Prevention Study, a large population-based, multicenter case-control study of major birth defects in the United States. Mothers of cases (n = 152) and control infants without a birth defect (n = 9,178) completed an interview which included a food frequency questionnaire capturing usual dietary intake in the year before pregnancy. Maternal nutrition was assessed through individual nutrient intake, calculating a Diet Quality Index for Pregnancy (DQI-P) score for each mother, and using latent class analysis to empirically derive four dietary patterns. We calculated adjusted odds ratios (aORs) and 95% confidence intervals (CI) using logistic regression. The results for individual nutrients varied, with some having an inverse or U-shaped pattern of association with increasing intake. The DQI-P was not associated with risk of PCG and ASDs (aOR 0.91; CI 0.49-1.66, highest vs. lowest quartile). The dietary pattern analysis suggested lower odds among women with a Prudent and Mexican dietary pattern (aOR 0.82, 95% CI 0.52-1.29; aOR 0.80, 95% CI 0.36-1.78, respectively) compared to those with a Western dietary pattern. We found that higher intake of some nutrients and certain dietary patterns may be inversely associated with PCG and ASDs, though caution is urged due to imprecision of estimates.

Risk factors for congenital heart disease: The Baby Hearts Study, a population-based case-control study

We investigated the role of maternal environmental factors in the aetiology of congenital heart disease (CHD). A population-based case-control study (242 CHD cases, 966 controls) was conducted using an iPad questionnaire for mother with linkage to maternity and first trimester prescription records. Risk of CHD was associated with low maternal education (OR adjusted for confounders 1.59; 95% confidence interval [CI], 1.02-2.49), pregestational diabetes (OR 4.04; 95% CI 1.00-16.28), self-reported maternal clotting disorders (adjOR 8.55, 95%CI 1.51-48.44), prescriptions for the anticlotting medication enoxaparin (adjOR 3.22, 95%CI 1.01-10.22) and self-reported vaginal infections (adjOR 1.69, 95%CI 1.01-2.80). There was no strong support for the hypothesis that periconceptional folic acid supplements have a protective effect, but there was a protective effect of frequent consumption of folate rich fruits (adjOR 0.64, 95%CI 0.47-0.89). Compared to the most common pre-pregnancy dietary pattern, CHD risk was associated with a poor diet low in fruit and vegetables (adjOR 1.56, 95%CI 1.05-2.34). Mothers of cases reported more pregnancy related stress (adjOR 1.69; 95% CI 1.22-2.34) and multiple stressors (adjOR 1.94, 95%CI 0.83-4.53). We found no supportive evidence for CHD risk being associated with obesity, smoking, depression or antidepressant use in this population. Our findings add to the previous evidence base to show potential for public health approaches to help prevent CHD in future by modifying environmental factors. Independent confirmation should be sought regarding elevated CHD risk associated with maternal blood clotting disorders and their treatment, since we are the first to report this.

Maternal Dietary Patterns during Pregnancy and Congenital Heart Defects: A Case-Control Study

Limited studies investigating the relationships between dietary patterns and congenital heart defects (CHDs) are available. This study aimed to explore the associations between dietary patterns and CHDs risk in Shaanxi, China. We conducted a hospital-based case-control study and included a total of 474 cases and 948 controls. Pregnant women waiting for delivery in the hospital were interviewed to report their diets during pregnancy using a validated food frequency questionnaire. Dietary patterns were derived using principal component factor analysis. Mixed logistic regression models were used to assess the associations between dietary patterns and CHDs. Pregnant women in the highest tertile of the prudent pattern had a lower risk of CHDs compared to those in the lowest tertile (OR = 0.65, 95%CI: 0.48–0.89). Pregnant women with high scores on the vegetarian pattern were at an increased risk of CHDs (medium vs. lowest tertile: OR = 1.50, 95%CI = 1.03–2.17; highest vs. lowest tertile: OR = 1.56, 95%CI = 1.13–2.15; p_trend = 0.015). Pregnant women with high scores on the dairy and egg pattern were at a reduced risk of CHDs (medium vs. lowest tertile: OR = 0.66, 95%CI = 0.49–0.90; highest vs. lowest tertile: OR = 0.60, 95%CI = 0.43–0.82; p_trend = 0.001). Maternal diet during pregnancy is an important target for intervention, and it may influence the likelihood of developing CHDs.

Association of maternal disease and medication use with the risk of congenital heart defects in offspring: a case-control study using logistic regression with a random-effects model

Objective To examine the association between maternal diseases and congenital heart defects (CHDs) and to evaluate whether those associations vary with corresponding medication use. Methods A multi-hospital case-control study conducted from February 2010 to December 2014 analysed 916 controls and 1236 cases. Participating mothers were asked whether they suffered from influenza, common cold, herpes and threatened abortion or had used corresponding medication during the periconception period or the early pregnancy period. We used a random-effects logistic regression model to compute the odds ratios (ORs), adjusted odds ratios (AORs) and 95% confidence intervals (CIs) while controlling for potential confounders. Results Compared with the results for mothers with no exposure, there were significant associations between maternal diseases with medication non-use and CHDs in the aggregate, including influenza (AOR, 1.83; 95% CI, 1.13-2.95), common cold (AOR, 2.05; 95% CI, 1.60-2.64) and herpes (AOR, 7.00; 95% CI, 2.15-22.84). There was no significant association between medication users and offspring with any subtype of CHDs, except that maternal common cold with medication use slightly increased the risk of the specific subtype, namely, isolated cardiac defects. However, an association was observed between maternal threatened abortion and medication and isolated cardiac defects (AOR, 1.33; 95% CI, 1.01-1.75). Conclusion Maternal influenza, common cold, herpes and threatened abortion from 3 months before pregnancy through the first trimester were associated with an increased risk of congenital heart disease in offspring. The teratogenic effect of these conditions may be attenuated by medication use, except for threatened abortion.

Risk factors associated with the development of double-inlet ventricle congenital heart disease

BACKGROUND

Congenital heart disease (CHD) is the most common birth defect group and a significant contributor to neonatal and infant death. CHD with single ventricle anatomy, including hypoplastic left heart syndrome (HLHS), tricuspid atresia (TA), and various double-inlet ventricle (DIV) malformations, is the most complex with the highest mortality. Prenatal risk factors associated with HLHS have been studied, but such data for DIV are lacking.

METHODS

We analyzed DIV cases and nonmalformed controls in the National Birth Defects Prevention Study, a case-control, multicenter population-based study of birth defects. Random forest analysis identified potential predictor variables for DIV, which were included in multivariable models to estimate effect magnitude and directionality.

RESULTS

Random forest analysis identified pre-pregnancy diabetes, history of maternal insulin use, maternal total lipid intake, paternal race, and intake of several foods and nutrients as potential predictors of DIV. Logistic regression confirmed pre-pregnancy diabetes, maternal insulin use, and paternal race as risk factors for having a child with DIV. Additionally, higher maternal total fat intake was associated with a reduced risk.

CONCLUSIONS

Maternal pre-pregnancy diabetes and history of insulin use were associated with an increased risk of having an infant with DIV, while maternal lipid intake had an inverse association. These novel data provide multiple metabolic pathways for investigation to identify better the developmental etiologies of DIV and suggest that public health interventions targeting diabetes prevention and management in women of childbearing age could reduce CHD risk.

No independent associations between preconception paternal dietary patterns and embryonic growth; the Predict Study

BACKGROUND & AIM

Several studies show the importance of periconceptional maternal dietary patterns on human embryonic growth. Healthy paternal nutrition has been associated with better semen quality and fecundability, however, evidence on the impact on pregnancy outcome is limited. Therefore, the aim of this study was to investigate the association between preconception paternal dietary patterns and first trimester embryonic growth using the parameters longitudinal crown-rump length (CRL) and embryonic volume (EV).

METHODS

A total of 638 couples were enrolled in the Rotterdam Periconceptional Cohort and received longitudinal three dimensional transvaginal ultrasound scans from 7⁺⁰ up to 12⁺⁰ weeks of gestation. Virtual reality software was used to perform offline measurements of the embryonic CRL and EV. Food frequency questionnaires (FFQ) were used to estimate habitual food intake in couples. Principal component analysis (PCA) was performed to identify paternal and maternal dietary patterns. Linear mixed models adjusted for potential confounders were applied to analyze associations between paternal and maternal dietary patterns and embryonic growth parameters.

RESULTS

The paternal dietary patterns retrieved were identified as "Whole wheat grains and Vegetables", "Sauces and Snacks Refined Grains", "Fish and Legumes" and explained 27.5% of the total variance of the dietary intake. No significant additional effects, independent of maternal dietary patters and other maternal and paternal potential confounders, were shown of these paternal dietary patterns on embryonic growth in spontaneous or IVF/ICSI pregnancies.

CONCLUSION

No significant effects of paternal dietary patterns independent of maternal dietary patters and other parental potential confounders on embryonic growth parameters could be established in spontaneous or IVF/ICSI pregnancies. The biological importance of paternal nutrition on semen quality, however, supports the need of periconceptional tailored nutritional counselling of couples trying to conceive.

Sex consideration in diet-biomarker-related indices: a systematic review

OBJECTIVE

An index of biomarkers derived from dietary factors (diet-biomarker-related index) identifies foods and nutrients that encompass physiological potentials and provides scientific evidence for dietary patterns that increase the risk of disease associated with specific biomarkers. Although men and women have different dietary patterns and physiological characteristics, sex is not often considered when investigators develop a diet-biomarker-related index. We aimed to review whether epidemiological studies developed diet-biomarker-related indices in a sex-specific way.

DESIGN

We systematically searched for epidemiological studies that developed diet-biomarker-related indices, including (i) biomarker prediction indices that include dietary factors as explanatory variables and (ii) dietary patterns to explain biomarker variations, in the PubMed and EMBASE databases. We qualitatively reviewed the sex consideration in index development.

RESULTS

We identified seventy-nine studies that developed a diet-biomarker-related index. We found that fifty-four studies included both men and women. Of these fifty-four studies, twenty-nine (53·7 %) did not consider sex, eleven (20·3 %) included sex in the development model, seven (13·0 %) considered sex but did not include sex in the development model, and seven (13·0 %) derived a diet-biomarker-related index for men and women separately. A list of selected dietary factors that explained levels of biomarkers generally differed by sex in the studies that developed a diet-biomarker-related index in a sex-specific way.

CONCLUSIONS

Most studies that included both men and women did not develop the diet-biomarker-related index in a sex-specific way. Further research is needed to identify whether a sex-specific diet-biomarker-related index is more predictive of the disease of interest than an index without sex consideration.

Early first trimester maternal 'high fish and olive oil and low meat' dietary pattern is associated with accelerated human embryonic development

BACKGROUND/OBJECTIVES

Maternal dietary patterns were associated with embryonic growth and congenital anomalies. We aim to evaluate associations between early first trimester maternal dietary patterns and embryonic morphological development among pregnancies with non-malformed outcome.

SUBJECTS/METHODS

A total of 228 strictly dated, singleton pregnancies without congenital malformations were enrolled in a periconceptional hospital-based cohort. Principal component analysis was performed to extract early first trimester maternal dietary patterns from food frequency questionnaires. Serial transvaginal three-dimensional ultrasound (3D US) scans were performed between 6⁺⁰ and 10⁺² gestational weeks and internal and external morphological criteria were used to define Carnegie stages in a virtual reality system. Associations between dietary patterns and Carnegie stages were investigated using linear mixed models.

RESULTS

A total of 726 3D US scans were included (median: three scans per pregnancy). The 'high fish and olive oil and low meat' dietary pattern was associated with accelerated embryonic development in the study population (β = 0.12 (95%CI: 0.00; 0.24), p < 0.05). Weak adherence to this dietary pattern delayed embryonic development by 2.1 days (95%CI: 1.6; 2.6) compared to strong adherence. The 'high vegetables, fruit and grain' dietary pattern accelerated embryonic development in the strictly dated spontaneous pregnancy subgroup without adjustment for energy intake.

CONCLUSIONS

Early first trimester maternal dietary patterns impacts human embryonic morphological development among pregnancies without congenital malformations. The clinical meaning of delayed embryonic development needs further investigation.

1H NMR-based metabolomics reveals the effect of maternal habitual dietary patterns on human amniotic fluid profile

Maternal diet may influence offspring’s health, even within well-nourished populations. Amniotic fluid (AF) provides a rational compartment for studies on fetal metabolism. Evidence in animal models indicates that maternal diet affects AF metabolic profile; however, data from human studies are scarce. Therefore, we have explored whether AF content may be influenced by maternal diet, using a validated food-frequency questionnaire and implementing NMR-based metabolomics. Sixty-five AF specimens, from women undergoing second-trimester amniocentesis for prenatal diagnosis, were analysed. Complementary, maternal serum and urine samples were profiled. Hierarchical cluster analysis identified 2 dietary patterns, cluster 1 (C1, n = 33) and cluster 2 (C2, n = 32). C1 was characterized by significantly higher percentages of energy derived from refined cereals, yellow cheese, red meat, poultry, and “ready-to-eat” foods, while C2 by higher (P < 0.05) whole cereals, vegetables, fruits, legumes, and nuts. ¹H NMR spectra allowed the identification of metabolites associated with these dietary patterns; glucose, alanine, tyrosine, valine, citrate, cis-acotinate, and formate were the key discriminatory metabolites elevated in C1 AF specimens. This is the first evidence to suggest that the composition of AF is influenced by maternal habitual dietary patterns. Our results highlight the need to broaden the knowledge on the importance of maternal nutrition during pregnancy.

A compromised maternal vitamin D status is associated with congenital heart defects in offspring

BACKGROUND

Interactions between genetic and environmental factors, including modifiable maternal nutrition and lifestyle, play a significant role in the pathogenesis of most congenital heart defects (CHD). The aim of this study was to investigate associations between periconceptional maternal vitamin D status and the prevalence of CHD in offspring.

METHODS

A case-control study was performed in 345 mothers of a child with CHD and 432 mothers of a child without CHD from four tertiary hospitals in the Netherlands between 2003 and 2005. Approximately 15months after pregnancy mothers filled out questionnaires regarding general characteristics and periconceptional lifestyle. Maternal blood was obtained to determine serum 25-hydroxyvitamin D and lipid concentrations. The 25-hydroxyvitamin D concentration was stratified into a deficient <50nmol/l, moderate 50-75nmol/l and adequate >75nmol/l status. Logistic regression was performed to study associations between vitamin D status and CHD risk, adjusted for maternal age, body mass index, ethnicity, smoking and total cholesterol concentration.

RESULTS

Case mothers less often had an adequate vitamin D status compared with controls (27% vs. 38%; p=0.002). The use of multivitamin supplements, ethnicity, season and body mass index were associated with vitamin D concentrations. A moderate (odds ratio 1.58, [95%CI 1.08, 2.32]) and deficient (odds ratio 2.15, [95%CI 1.44-3.19]) vitamin D status were associated with CHD in offspring.

CONCLUSION

A compromised maternal vitamin D status is associated with an approximately two-fold increased prevalence of CHD in offspring. Therefore, improvement of the periconceptional maternal vitamin D status is recommended.

Using latent class cluster analysis to screen high risk clusters of birth defects between 2009 and 2013 in Northwest China

In the study, we aimed to explore the synergistic effects of multiple risk factors on birth defects, and examine temporal trend of the synergistic effects over time. Two cross-sectional surveys conducted in 2009 and 2013 were merged and then latent class cluster analysis and generalized linear Poisson model were used. A total of 9085 and 29094 young children born within the last three years and their mothers were enrolled in 2009 and 2013 respectively. Three latent maternal exposure clusters were determined: a high-risk, a moderate-risk, and a low-risk cluster (88.97%, 1.49%, 9.54% in 2009 and 82.42%, 3.39%, 14.19% in 2013). The synthetic effects of maternal exposure to multiple risk factors could increase the risk of overall birth defects and cardiovascular system malformation among live births, and this risk is significantly higher in high-risk cluster than that in low-risk cluster. After adjusting for confounding factors using a generalized linear Poisson model, in high-risk cluster the prevalence of nervous system malformation decreased by approximately 2.71%, and the proportion of cardiovascular system malformation rose by 0.92% from 2009 to 2013. The Chinese government should make great efforts to provide primary prevention for those on high-risk cluster as a priority target population.

Pre-Pregnancy Body Mass Index Is Associated with Dietary Inflammatory Index and C-Reactive Protein Concentrations during Pregnancy

There have been a limited number of studies examining the association between pre-pregnancy body mass index (BMI) and dietary inflammation during pregnancy. Our aim is to examine the association between pre-pregnancy BMI and the Dietary Inflammatory Index (DII)™ and C-reactive protein (CRP) concentrations during pregnancy. The study included 631 pregnant American women from the National Health and Nutrition Examination Survey (NHANES) cross-sectional examinations from 2003 to 2012. Pre-pregnancy BMI was calculated based on self-reported pre-pregnancy weight and measured height. The cut-offs of <18.5 (underweight), 18.5-24.9 (normal), 25.0-29.9 (overweight), and ≥30 kg/m² (obese) were used to categorize the weight status of pregnant women prior to pregnancy. The DII, a literature-based dietary index to assess the inflammatory properties of diet, was estimated based on a one-day 24-h recall. Multivariable linear and logistic regressions were performed to estimate beta coefficients and the adjusted odds ratios (AORs) and 95% confidence intervals (95% CIs) on the association of pre-pregnancy BMI categories with the DII and CRP concentrations during pregnancy. After controlling for variables including: race/ethnicity, family poverty income ratio, education, marital status, month in pregnancy, and smoking status during pregnancy; women who were obese before pregnancy (n = 136) had increased odds for being in the highest tertile of the DII and CRP concentrations compared to women with normal weight (AORs 2.40, 95% CIs 1.01-5.71; AORs 24.84, 95% CIs 6.19-99.67, respectively). These findings suggest that women with pre-pregnancy obesity had greater odds of reporting higher DII and having elevated CRP. In conclusion, high pre-pregnancy BMI was associated with increased odds of pro-inflammatory diet and elevated CRP levels during pregnancy in the USA.

Dietary patterns and the phenotype of polycystic ovary syndrome: the chance of ongoing pregnancy

Polycystic ovary syndrome (PCOS) is generally considered a complex disorder caused by interactions between genetic and environmental factors. In a sub-cohort of women with PCOS visiting the preconception outpatient clinic of a tertiary hospital with follow-up in a periconception cohort, we identified specific dietary patterns and adherence in patients with PCOS with and without hyperandrogenism and the chance of ongoing pregnancy. Food frequency questionnaires were available from 55 patients diagnosed with PCOS during follow-up in routine clinical practice, including 25 with hyperandrogenism and 30 without hyperandrogenism. Strong adherence to the healthy dietary pattern was inversely associated with the hyperandrogenic PCOS phenotype (Adjusted OR 0.27; 95% CI 0.07 to 0.99). In women with PCOS overall, a strong adherence to the healthy dietary pattern showed a three-fold higher chance of ongoing pregnancy (adjusted OR 3.38; 95% CI 1.01 to 11.36) and an association with anti-Müllerian hormone concentration (β -0.569 µg/L; 95% CI -0.97 to -0.17). The effect of this dietary pattern on the chance of ongoing pregnancy and AMH suggests causality, which needs further investigation in prospective studies in the general population.

Genome-wide methylation analysis identifies novel CpG loci for perimembranous ventricular septal defects in human

Aim: Congenital heart diseases are the most common birth defects worldwide and leading cause of infant mortality. The perimembranous ventricular septal defect is most prevalent. Epigenetics may provide an underlying mechanism of the gene–environment interactions involved. Materials & methods: We examined epigenome-wide DNA methylation using the Illumina HumanMethylation450 BeadChip in 84 case children and 196 control children. Results: We identified differential methylation of a CpG locus (cg17001566) within the PRDM16 gene after Bonferroni correction (p = 9.17 × 10-8). This was validated by bisulfite pyrosequencing. PRDM16 functions as a repressor of TGF-β signaling controlling tissue morphogenesis crucial during cardiogenesis. At 15% false-discovery rate, we identified seven additional CpG loci. Conclusion: These findings provide novel insights in the pathogenesis of perimembranous ventricular septal defect, which is of interest for future prediction and prevention.

Maternal diet quality in pregnancy and neonatal adiposity: the Healthy Start Study

BACKGROUND/OBJECTIVES

Poor maternal diet in pregnancy can influence fetal growth and development. We tested the hypothesis that poor maternal diet quality during pregnancy would increase neonatal adiposity (percent fat mass (%FM)) at birth by increasing the fat mass (FM) component of neonatal body composition.

METHODS

Our analysis was conducted using a prebirth observational cohort of 1079 mother-offspring pairs. Pregnancy diet was assessed via repeated Automated Self-Administered 24-h dietary recalls, from which Healthy Eating Index-2010 (HEI-2010) scores were calculated for each mother. HEI-2010 was dichotomized into scores of ⩽57 and >57, with low scores representing poorer diet quality. Neonatal %FM was assessed within 72 h after birth with air displacement plethysmography. Using univariate and multivariate linear models, we analyzed the relationship between maternal diet quality and neonatal %FM, FM, and fat-free mass (FFM) while adjusting for prepregnancy body mass index (BMI), physical activity, maternal age, smoking, energy intake, preeclampsia, hypertension, infant sex and gestational age.

RESULTS

Total HEI-2010 score ranged between 18.2 and 89.5 (mean: 54.2, s.d.: 13.6). An HEI-2010 score of ⩽57 was significantly associated with higher neonatal %FM (β=0.58, 95% confidence interval (CI) 0.07-1.1, P<0.05) and FM (β=20.74; 95% CI 1.49-40.0; P<0.05) but no difference in FFM.

CONCLUSIONS

Poor diet quality during pregnancy increases neonatal adiposity independent of maternal prepregnancy BMI and total caloric intake. This further implicates maternal diet as a potentially important exposure for fetal adiposity.

Lower rate of selected congenital heart defects with better maternal diet quality: a population-based study

OBJECTIVE

To evaluate whether better diet quality in mothers is associated with lower risk for major non-syndromic congenital heart defects in their children.

DESIGN

Multicentre population-based case-control study, the National Birth Defects Prevention Study.

SETTING

Ten sites in the USA.

PARTICIPANTS

Mothers of babies with major non-syndromic congenital heart defects (n=9885) and mothers with unaffected babies (n=9468) with estimated date of delivery from 1997 to 2009.

MAIN OUTCOME MEASURES

Adjusted ORs for specific major congenital heart defects by quartiles of maternal diet quality in the year before pregnancy, assessed by the Diet Quality Index for pregnancy (DQI-P) and the Mediterranean Diet Score. Quartile 1 (Q1) reflecting the worst diet quality and Q4 the best diet quality.

RESULTS

Better diet quality was associated with reduced risk for some conotruncal and atrial septal heart defects. For DQI-P, estimated risks reductions (Q4 vs Q1) for conotruncal defects were 37% for tetralogy of Fallot (OR 0.63, 95% CI 0.49 to 0.80) and 24% overall (OR 0.76, 95% CI 0.64 to 0.91); and for septal defects, 23% for atrial septal defects (OR 0.77, 95% CI 0.63 to 0.94) and 14% overall (OR 0.86, 95% CI 0.75 to 1.00). Risk reductions were weaker or minimal for most other major congenital heart defects.

CONCLUSIONS

Better diet quality is associated with a reduced occurrence of some conotruncal and septal heart defects. This finding suggests that a reduction in certain cardiac malformations may be an additional benefit of improved maternal diet quality, reinforcing current preconception care recommendations.

Dietary Patterns during Pregnancy Are Associated with Risk of Gestational Diabetes Mellitus

Maternal dietary patterns before and during pregnancy play important roles in the development of gestational diabetes mellitus (GDM). We aimed to identify dietary patterns during pregnancy that are associated with GDM risk in pregnant U.S. women. From a 24 h dietary recall of 253 pregnant women (16–41 years) included in the National Health and Nutrition Examination Survey (NHANES) 2003–2012, food items were aggregated into 28 food groups based on Food Patterns Equivalents Database. Three dietary patterns were identified by reduced rank regression with responses including prepregnancy body mass index (BMI), dietary fiber, and ratio of poly- and monounsaturated fatty acids to saturated fatty acid: “high refined grains, fats, oils and fruit juice”, “high nuts, seeds, fat and soybean; low milk and cheese”, and “high added sugar and organ meats; low fruits, vegetables and seafood”. GDM was diagnosed using fasting plasma glucose levels ≥5.1 mmol/L for gestation <24 weeks. Multivariable logistic regression models were used to estimate adjusted odds ratio (AOR) and 95% confidence intervals (CIs) for GDM, after controlling for maternal age, race/ethnicity, education, family poverty income ratio, marital status, prepregnancy BMI, gestational weight gain, energy intake, physical activity, and log-transformed C-reactive protein (CRP). All statistical analyses accounted for the appropriate survey design and sample weights of the NHANES. Of 249 pregnant women, 34 pregnant women (14%) had GDM. Multivariable AOR (95% CIs) of GDM for comparisons between the highest vs. lowest tertiles were 4.9 (1.4–17.0) for “high refined grains, fats, oils and fruit juice” pattern, 7.5 (1.8–32.3) for “high nuts, seeds, fat and soybean; low milk and cheese” pattern, and 22.3 (3.9–127.4) for “high added sugar and organ meats; low fruits, vegetables and seafood” pattern after controlling for maternal sociodemographic variables, prepregnancy BMI, gestational weight gain, energy intake and log-transformed CRP. These findings suggest that dietary patterns during pregnancy are associated with risk of GDM after controlling for potential confounders. The observed connection between a high consumption of refined grains, fat, added sugars and low intake of fruits and vegetables during pregnancy with higher odds for GDM, are consistent with general health benefits of healthy diets, but warrants further research to understand underlying pathophysiology of GDM associated with dietary behaviors during pregnancy.

Validation of a food-frequency questionnaire assessment of methyl-group donors using estimated diet records and plasma biomarkers: the method of triads

In this study, the intake of methyl-group donors (methionine, folate, betaine, and choline) among Flemish women of reproductive age (n = 30) assessed by a 7-d estimated diet record (7 d EDR) and food-frequency questionnaire (FFQ) was compared with plasma S-adenosylmethionine (SAM), S-adenosylhomocysteine (SAH), and SAH:SAM ratio. Pearson correlation coefficients were calculated between each of the dietary methods and the validity coefficient was calculated using the method of triads. Correlations were higher between intake assessed by the FFQ and biomarkers than between 7 d EDR and biomarkers. The validity coefficients of the FFQ, when using SAH as a biomarker, were high (0.86 for methionine to 0.94 for folate), when the SAH:SAM ratio was used as a biomarker the validity coefficients ranged from 0.63 to 1.00. These data indicate that the FFQ is a reliable tool to estimate the intake of the methyl-group donors in women of reproductive age.

Maternal dietary patterns are associated with risk of neural tube and congenital heart defects

Studying empirically derived dietary patterns is useful in understanding dietary practice. We classified women by their dietary patterns using latent class analysis of 66 foods and studied the association of these patterns with neural tube defects (NTDs) and congenital heart defects (CHDs) in the U.S. National Birth Defects Prevention Study (1997-2005). Logistic regression models used data from 1,047 with an NTD, 6,641 with a CHD, and 6,123 controls that were adjusted for maternal characteristics and tested the effect modification of multivitamin supplement use. Four latent dietary patterns were identified: prudent, Western, low-calorie Western, and Mexican. Among participants who did not use supplements, those in the Mexican, Western, and low-calorie Western classes were significantly more likely (odds ratios of 1.6, 1.5, and 1.4, respectively) to have offspring born with NTDs than were those in the prudent class after adjustment of for dietary folic acid intake. In contrast, among supplement users, there was no difference in the incidence of NTDs between classes. Associations between dietary class and CHD subgroups were not modified by supplement use except for tetralogy of Fallot; among supplement users, those in the Western class were twice as likely (95% confidence interval: 1.4, 2.8) as the prudent class to have offspring with tetralogy of Fallot. Women who adhered to a Western diet were 1.2 (95% confidence interval: 1.03, 1.35) times more likely to have an infant with septal heart defect than were women who adhered to a prudent diet. A prudent dietary pattern, even with folate fortification, may decrease the risk of NTDs and some heart defects.

Alteration in methylation pattern of GATA-4 promoter region in vitamin A-deficient offspring's heart

Epigenetics might explain correlations between lifestyle and risk of disease. Maternal diet has been shown to dynamically alter epigenetic regulation, including affecting DNA methylation status. This study was designed to test the hypothesis that GATA-4 gene methylation would lead to congenital heart defects in vitamin A-deficient offspring. Ten weaning female rats (VAN group) were fed with a diet which contents 4 IU vitamin A/g diet, while 20 rats (VAD group) were maintained on a diet without vitamin A. After 10 weeks of feeding, all the female rats were mated with normal male rats. The VAN group and a portion of VAD group rats were still given the same diet as before mating, while the rest of the rats from the VAD group (VADS group) were transferred to a diet with enough added vitamin A (10 IU/g diet) for the pregnancy cycle. The embryo hearts were dissected out at embryonic day 13.5 (E13.5) for observation of cardiac development, GATA-4 gene methylation status and the expression of DNA methyltransferases (DNMTs). Embryos from vitamin A-deficient group exhibited a high incidence of cardiac defects. High methylation was present in the CpG loci of GATA-4 gene with a low expression of GATA-4 mRNA from vitamin A-deficient group embryos. Moreover, up-regulation of DNMT1 and down-regulation of DNMT3a and DNMT3b expression were found in this group embryo. These findings show that aberrant methylation is one of key mechanisms to heart defects in vitamin A-deficient offspring. DNMTs play a critical role in this process.