Association Between Maternal Folic Acid Supplementation and Congenital Heart Defects in Offspring in Birth Cohorts From Denmark and Norway

Relationships between Maternal Folic Acid Supplementation and GATA4 Gene Polymorphisms in Patients with Non-Chromosomal Congenital Heart Disease: A Hospital-Based Case-Control Study in China

This study aimed to investigate the relationships between maternal FA supplementation and nine single-nucleotide variants of the GATA4 gene in non-chromosomal CHD and further explore the gene-environment interactions associated with CHD. A total of 585 CHD patients and 600 controls were recruited in the case-control study. Maternal FA (FA-containing multivitamin) supplementation information and nine polymorphisms of the GATA4 gene were collected in this study. Adjusted ORs (aOR) and their 95% confidence intervals (CIs) were calculated using proper statistical methods to analyze the relationships between the two main exposures of interest with respect to CHD. After adjusting the suspicious confounding factors, a significantly increased risk for CHD in offspring was found with non-FA supplementation before/during the pregnancy to CHD in offspring (aOR = 1.58, 95% CI: 1.01-2.48). We suggested taking FA supplementation before/during the pregnancy to prevent CHD in offspring, especially in the preconception period (aOR = 0.53, 95% CI: 0.32-0.90). The genetic results showed that the polymorphisms of rs4841588, rs12458, and rs904018 under specific genotypes and genetic models were significantly related to CHD. The gene-environment interaction between rs10108052 and FA supplementation before/during pregnancy could increase the risk of CHD (aOR = 5.38, 95% CI: 1.67-17.09, Pinteraction = 0.004). Relationships between maternal FA supplementation and specific polymorphisms of the GATA4 gene, as well as the gene-environment interaction, were significantly associated with CHD in offspring.

Association Between Maternal Factors in Early Pregnancy and Congenital Heart Defects in Offspring: The Japan Environment and Children's Study

Background Many prenatal factors are reported to be associated with congenital heart defects (CHD) in offspring. However, these associations have not been adequately examined using large-scale birth cohorts. Methods and Results We evaluated a data set of the Japan Environmental and Children's Study. The primary outcome was a diagnosis of CHD by age 2 years. We defined the following variables as exposures: maternal baseline characteristics, fertilization treatment, maternal history of diseases, socioeconomic status, maternal alcohol intake, smoking, tea consumption, maternal dietary intake, and maternal medications and supplements up to 12 weeks of gestation. We used multivariable logistic regression analysis to assess the associations between various exposures and CHD in offspring. A total of 91 664 singletons were included, among which 1264 (1.38%) had CHD. In multivariable analysis, vitamin A supplements (adjusted odds ratio [aOR], 5.78 [95% CI, 2.30-14.51]), maternal use of valproic acid (aOR, 4.86 [95% CI, 1.51-15.64]), maternal use of antihypertensive agents (aOR, 3.80 [95% CI, 1.74-8.29]), maternal age ≥40 years (aOR, 1.59 [95% CI, 1.14-2.20]), and high maternal hemoglobin concentration in the second trimester (aOR, 1.10 per g/dL [95% CI, 1.03-1.17]) were associated with CHD in offspring. Conclusions Using a Japanese large-scale birth cohort study, we found 6 maternal factors to be associated with CHD in offspring.

Determinants of neural tube defects among newborns in public referral hospitals in Eastern Ethiopia

BACKGROUND

Neural tube defects (NTDs) are serious brain and spine birth defects. Although NTDs are primarily pregnancy complications, such as abortion and stillbirth, they also contribute to under-five morbidity and mortality, as well as long-term disability and psychological impact. Despite these negative outcomes, the determinants of NTDs are not widely studied in Ethiopia, particularly in the country's east. As a result, we sought to identify the risk factors for NTDs in neonates born in public referral hospitals in eastern Ethiopia.

METHODS

A facility-based unmatched case-control study was carried out at Hiwot Fana Comprehensive Specialized Hospital and Sheik Hassen Yabare Jigjiga University Referral Hospital in Eastern Ethiopia. We included 59 cases identified in the selected facilities between September 10, 2021, and February 5, 2022, and 118 control neonates, with a case-to-control ratio of 1:2. Data were gathered through the use of interviewer-administered questionnaires and medical record review. To identify determinant factors of NTDs, a multivariable logistic regression model was used, which included all predictor variables from the bivariable analysis. The results were reported using an Adjusted Odds Ratio (AOR) with a 95% confidence interval. A p-value of < 0.05 was considered statistically significant.

RESULTS

In total, 59 cases of NTDs were identified out of 2915 live birth total births registered in the two hospitals, making the incidence of NTDs 202.4/10,000 births. In the final model analysis, determinant factors such as gender of newborn [AOR = 2.97; 95%CI(1.27, 6.92)], having no history of antenatal care[AOR = 4.45;95%CI(1.30,15.20)], having a poor food consumption score (AOR = 3.38;95% CI;1.06,10.72), having history of monotonous diet consumption (AOR = 4.80; 95%CI: 1.09, 9.08; P = 0.038), and coffee consumption of three or more cups per day during pregnancy (AOR = 3.84:95% CI: 1.23, 11.97) were statistically associated with NTDs.

CONCLUSION

Modifiable and non-modifiable determinants were identified as major contributors of neural tube defect in this study. Early screening, dietary intervention counseling to increase consumption of a healthy diet, coffee consumption reduction, and pre-pregnancy supplementation programs should be developed to reduce NTDs in Ethiopia.

Pre-gestational diabetes and the risk of congenital heart defects in the offspring: A French nationwide study

AIM

To compare the frequencies and types of congenital heart defects for infants of women without and with pre-gestational diabetes, type 1 and type 2 diabetes (T1DM, T2DM) and to identify risk factors.

METHODS

All live births between 2012 and 2020 were screened for maternal diabetes and infant congenital heart defects using the French Medical Information System Program in Medicine, Surgery and Obstetrics database (PMSI-MCO). Incidences of these defects were estimated, and a logistic model evaluated maternal and fetal prognostic risk factors.

RESULTS

Overall, 6,038,703 mothers did not have pre-gestational diabetes (no-diabetes), 23,147 had T1DM, and 14,401 had T2DM. The incidence of infant congenital disease was 6.2% for the no-diabetes group, 8.0%, for women with T1DM, and 8.4% for women with T2DM (P < 0.001); for congenital heart defects, incidences were respectively 0.8%, 3.0% and 2.7% (P < 0.001). In comparison with the no-diabetes group, the odds ratios (95%CI) of coronary heart defects were 2.07 (1.91;2.24) (P < 0.001) for women with T1DM and 2.20 (1.99;2.44) (P < 0.001) for women with T2DM, with no difference between T1DM and T2DM (P = 0.336). cesarian section, small and large for gestational age, and prematurity were also associated with an increased risk of congenital heart defects.

CONCLUSION

In this study we observed higher incidences of congenital heart defects in infants of women with pre-gestational diabetes compared to women without pre-gestational diabetes, with no difference between women with T1DM or T2DM. These data call for intensifying preconception care and justify systematic cardiac echography in selected fetuses.

Prenatal Carbamazepine Exposure and Academic Performance in Adolescents: A Population-Based Cohort Study

BACKGROUND AND OBJECTIVES

To investigate whether children born to mothers who used carbamazepine during pregnancy had worse academic performance in adolescence.

METHODS

This population-based cohort study included all live-born singletons in Denmark between 1996 and 2002 who participated in the national ninth-grade exit examination (n = 370,859). Those born to mothers with prescription of antiseizure medications other than carbamazepine during pregnancy were excluded. We examined the association of in utero exposure to maternal carbamazepine redeemed during pregnancy (n = 290) with academic performance of offspring, defined by the scores in Danish and mathematics in ninth-grade exit examination. We estimated mean z-score difference with linear regression adjusted for socioeconomic factors and potential indications, including epilepsy and medication for other psychiatric disorders. Additional analyses addressing confounding by indication included comparison between in utero exposed vs past exposed and between past exposed and never exposed. In utero exposure to valproate monotherapy was used as a positive control and in utero exposure to lamotrigine as a negative control.

RESULTS

At the age of 16.1 (SD 0.4) years, adolescents in utero exposed to maternal carbamazepine monotherapy had lower scores both in Danish and mathematics in ninth-grade exit examination (adjusted z-score difference, -0.14 [95% CI -0.24 to -0.05] and -0.17 [95% CI -0.28 to -0.07], respectively). In utero exposure to carbamazepine monotherapy was associated with lower scores than past exposure only (adjusted z-score difference, -0.24 [95% CI -0.41 to -0.06] for Danish and -0.25 [95% CI -0.44 to -0.06] for mathematics), while past exposure to carbamazepine was associated with minor decrease in offspring's academic performance (adjusted z-score difference, -0.02 [95% CI -0.09 to 0.06] for Danish and -0.07 [95% CI -0.16 to 0.01] for mathematics). The association was also observed for in utero exposure to valproate monotherapy, but not for in utero exposure to lamotrigine.

DISCUSSION

In utero exposure to carbamazepine was associated with poorer academic performance in adolescence, as represented by lower scores in ninth-grade exit examination in Danish and mathematics. Additional studies are needed to confirm these findings because of limitations in this study and variable findings in prior studies.

CLASSIFICATION OF EVIDENCE

This study provides Class III evidence that academic performance, as reflected in ninth-grade exit examinations in Danish and mathematics, was worse among those exposed to carbamazepine monotherapy in utero, compared with those without in utero exposure to antiseizure medications.

Is the Tradeoff between Folic Acid or/and Multivitamin Supplementation against Birth Defects in Early Pregnancy Reconsidered? Evidence Based on a Chinese Birth Cohort Study

BACKGROUND

Several studies have reported conflicting results on the association between maternal exposure to folic acid (FA) and/or multivitamin (MV) supplements and the risk of birth defects (BDs), especially for different subtypes of BDs. The present study aimed to identify the association between maternal exposure to FA or/and MV and BDs in offspring.

METHODS

In the Chinese Birth Cohort Study initiated from 20 November 2017, 120,652 pregnant women completed follow-up until 20 August 2021. The participants were classified into four groups: without exposure to FA and MV, exposure to only FA, exposure to only MV, and exposure to FA and MV. Birth defects were coded by the International Classification of Diseases (ICD)-10. In order to explore the structural relationship between maternal FA or MV supplements and BDs, directed acyclic graphs were drawn. Then, an inverse probability treatment weighting was utilized to reduce the systematic differences in the baseline characteristics among the different groups. Lastly, a two-level mixed-effect log binomial regression analysis was used to estimate the relative risk (RR) value of the different subtypes of BDs under different exposures to FA and/or MV.

RESULTS

Compared with the maternal group without exposure to FA and MV, the RR values of nervous system defects, face, ear, and neck defects, limb defects, and CHDs in the maternal group with only FA supplementation were less than 1.0, but they were not statistically significant. The RR values of genitourinary defects, abnormal chromosomes, and oral clefts were more than 1.0, and they were also not statistically significant. However, the risk of genitourinary defects (RR: 3.22, 95% CI: 1.42-7.29) and chromosomal abnormalities (RR: 2.57, 95% CI: 1.16-5.73) in the maternal group with only MV supplementation increased more than those in the maternal group without exposure to FA and MV. In addition, the RR values of all subtypes of BDs in the maternal group with exposure to FA and MV were closer to 1.0 than those in maternal group with exposure to only MV, but they were not statistically significant.

CONCLUSIONS

It was indicated that the simultaneous supplementation of FA and MV in early pregnancy may have an interaction for the prevention of BDs and may have inconsistent effects for different subtypes of BDs. At the same time, excessive FA supplementation in pregnant women may increase the risk of BDs in their offspring. Although the mechanism is not clear, this evidence reminded us that more trade-offs are necessary for formulating strategies for the prevention of BDs with FA and/or MV supplementation in early pregnancy.

Evaluation of Cardiovascular Toxicity of Folic Acid and 6S-5-Methyltetrahydrofolate-Calcium in Early Embryonic Development

Folic acid (FA) is a synthetic and highly stable version of folate, while 6S-5-methyltetrahydrofolate is the predominant form of dietary folate in circulation and is used as a crystalline form of calcium salt (MTHF-Ca). The current study aims to evaluate the toxicity and safety of FA and MTHF-Ca on embryonic development, with a focus on cardiovascular defects. We began to analyze the toxicity of FA and MTHF-Ca in zebrafish from four to seventy-two hours postfertilization and assessed the efficacy of FA and MTHF-Ca in a zebrafish angiogenesis model. We then analyzed the differently expressed genes in in vitro fertilized murine blastocysts cultured with FA and MTHF-Ca. By using gene-expression profiling, we identified a novel gene in mice that encodes an essential eukaryotic translation initiation factor (Eif1ad7). We further applied the morpholino-mediated gene-knockdown approach to explore whether the FA inhibition of this gene (eif1axb in zebrafish) caused cardiac development disorders, which we confirmed with qRT-PCR. We found that FA, but not MTHF-Ca, could inhibit angiogenesis in zebrafish and result in abnormal cardiovascular development, leading to embryonic death owing to the downregulation of eif1axb. MTHF-Ca, however, had no such cardiotoxicity, unlike FA. The current study thereby provides experimental evidence that FA, rather than MTHF-Ca, has cardiovascular toxicity in early embryonic development and suggests that excessive supplementation of FA in perinatal women may be related to the potential risk of cardiovascular disorders, such as congenital heart disease.

Periconception Red Blood Cell Folate and Offspring Congenital Heart Disease : Nested Case-Control and Mendelian Randomization Studies

BACKGROUND

Periconception folic acid supplementation has been suggested to protect against congenital heart disease (CHD), but the association between maternal red blood cell (RBC) folate, the gold-standard biomarker of folate exposure, and subsequent offspring CHD risk is lacking.

OBJECTIVE

To quantify the association between periconception maternal RBC folate and offspring CHD risk.

DESIGN

Prospective, nested, case-control study and 1-sample Mendelian randomization. (ClinicalTrials.gov: NCT02737644).

SETTING

29 maternity institutions in 12 districts of Greater Shanghai, China.

PARTICIPANTS

All 197 mothers of offspring with CHD and 788 individually matched mothers of unaffected offspring from the SPCC (Shanghai Preconception Cohort).

MEASUREMENTS

Maternal RBC folate was measured before or at early pregnancy. Odds ratios [ORs] were estimated using conditional logistic regression after adjustment for covariates. Mendelian randomization was done using the methylenetetrahydrofolate reductase (MTHFR) C677T as the genetic instrument.

RESULTS

Case patients had lower median maternal RBC folate concentrations than control participants (714 nmol/L [interquartile range, 482 to 1008 nmol/L] vs. 788 nmol/L [557 to 1094 nmol/L]). Maternal RBC folate concentrations were inversely associated with offspring CHD (adjusted OR per 100 nmol/L, 0.93 [95% CI, 0.89 to 0.99]). The adjusted OR for mothers with periconception RBC folate of 906 nmol/L or more (vs. <906 nmol/L) was 0.61 (CI, 0.40 to 0.93). Mendelian randomization showed that each 100-nmol increase in maternal RBC folate concentrations was significantly associated with reduced offspring CHD risk (OR, 0.75 [CI, 0.61 to 0.92]).

LIMITATION

Potential confounding due to unmeasured covariates in the nested case-control study.

CONCLUSION

Higher maternal RBC folate is associated with reduced offspring CHD risk. For primary CHD prevention, higher target RBC folate levels than currently recommended for neural tube defect prevention may be needed and warrant further study.

PRIMARY FUNDING SOURCE

National Key Research and Development Program of China, National Natural Science Foundation of China, China Postdoctoral Science Foundation, and Chinese Academy of Medical Sciences Innovation Fund for Medical Sciences.

Palmitic Acid Impedes Extravillous Trophoblast Activity by Increasing MRP1 Expression and Function

Normal function of placental extravillous trophoblasts (EVTs), which are responsible for uteroplacental vascular remodeling, is critical for adequate delivery of oxygen and nutrients to the developing fetus and normal fetal programming. Proliferation and invasion of spiral arteries by EVTs depends upon adequate levels of folate. Multidrug resistance-associated protein 1 (MRP1), which is an efflux transporter, is known to remove folate from these cells. We hypothesized that palmitic acid increases MRP1-mediated folate removal from EVTs, thereby interfering with EVTs' role in early placental vascular remodeling. HTR-8/SVneo and Swan-71 cells, first trimester human EVTs, were grown in the absence or presence of 0.5 mM and 0.7 mM palmitic acid, respectively, for 72 h. Palmitic acid increased ABCC1 gene expression and MRP1 protein expression in both cell lines. The rate of folate efflux from the cells into the media increased with a decrease in migration and invasion functions in the cultured cells. Treatment with N-acetylcysteine (NAC) prevented the palmitic acid-mediated upregulation of MRP1 and restored invasion and migration in the EVTs. Finally, in an ABCC1 knockout subline of Swan-71 cells, there was a significant increase in invasion and migration functions. The novel finding in this study that palmitic acid increases MRP1-mediated folate efflux provides a missing link that helps to explain how maternal consumption of saturated fatty acids compromises the in utero environment.

How Parental Predictors Jointly Affect the Risk of Offspring Congenital Heart Disease: A Nationwide Multicenter Study Based on the China Birth Cohort

Objective

Congenital heart disease (CHD) is complex in its etiology. Its genetic causes have been investigated, whereas the non-genetic factor related studies are still limited. We aimed to identify dominant parental predictors and develop a predictive model and nomogram for the risk of offspring CHD.

Methods

This was a retrospective study from November 2017 to December 2021 covering 44,578 participants, of which those from 4 hospitals in eastern China were assigned to the development cohort and those from 5 hospitals in central and western China were used as the external validation cohort. Univariable and multivariable analyses were used to select the dominant predictors of CHD among demographic characteristics, lifestyle behaviors, environmental pollution, maternal disease history, and the current pregnancy information. Multivariable logistic regression analysis was used to construct the model and nomogram using the selected predictors. The predictive model and the nomogram were both validated internally and externally. A web-based nomogram was developed to predict patient-specific probability for CHD.

Results

Dominant risk factors for offspring CHD included increased maternal age [odds ratio (OR): 1.14, 95% CI: 1.10–1.19], increased paternal age (1.05, 95% CI: 1.02–1.09), maternal secondhand smoke exposure (2.89, 95% CI: 2.22–3.76), paternal drinking (1.41, 95% CI: 1.08–1.84), maternal pre-pregnancy diabetes (3.39, 95% CI: 1.95–5.87), maternal fever (3.35, 95% CI: 2.49–4.50), assisted reproductive technology (2.89, 95% CI: 2.13–3.94), and environmental pollution (1.61, 95% CI: 1.18–2.20). A higher household annual income (100,000–400,000 CNY: 0.47, 95% CI: 0.34–0.63; &gt; 400,000 CNY: 0.23, 95% CI: 0.15–0.36), higher maternal education level (13–16 years: 0.68, 95% CI: 0.50–0.93; ≥ 17 years: 0.87, 95% CI: 0.55–1.37), maternal folic acid (0.21, 95% CI: 0.16–0.27), and multivitamin supplementation (0.33, 95% CI: 0.26–0.42) were protective factors. The nomogram showed good discrimination in both internal [area under the receiver-operating-characteristic curve (AUC): 0.843] and external validations (development cohort AUC: 0.849, external validation cohort AUC: 0.837). The calibration curves showed good agreement between the nomogram-predicted probability and actual presence of CHD.

Conclusion

We revealed dominant parental predictors and presented a web-based nomogram for the risk of offspring CHD, which could be utilized as an effective tool for quantifying the individual risk of CHD and promptly identifying high-risk population.

Accelerated Cardiac Aging in Patients With Congenital Heart Disease

An increasing number of patients with congenital heart disease (CHD) survive into adulthood but develop long-term complications including heart failure (HF). Cellular senescence, classically defined as stable cell cycle arrest, is implicated in biological processes such as embryogenesis, wound healing, and aging. Senescent cells have a complex senescence-associated secretory phenotype (SASP), involving a range of pro-inflammatory factors with important paracrine and autocrine effects on cell and tissue biology. While senescence has been mainly considered as a cause of diseases in the adulthood, it may be also implicated in some of the poor outcomes seen in patients with complex CHD. We propose that patients with CHD suffer from multiple repeated stress from an early stage of the life, which wear out homeostatic mechanisms and cause premature cardiac aging, with this term referring to the time-related irreversible deterioration of the organ physiological functions and integrity. In this review article, we gathered evidence from the literature indicating that growing up with CHD leads to abnormal inflammatory response, loss of proteostasis, and precocious age in cardiac cells. Novel research on this topic may inspire new therapies preventing HF in adult CHD patients.

Genome-Wide De Novo Variants in Congenital Heart Disease Are Not Associated With Maternal Diabetes or Obesity

BACKGROUND

Congenital heart disease (CHD) is the most common anomaly at birth, with a prevalence of ≈1%. While infants born to mothers with diabetes or obesity have a 2- to 3-fold increased incidence of CHD, the cause of the increase is unknown. Damaging de novo variants (DNV) in coding regions are more common among patients with CHD, but genome-wide rates of coding and noncoding DNVs associated with these prenatal exposures have not been studied in patients with CHD.

METHODS

DNV frequencies were determined for 1812 patients with CHD who had whole-genome sequencing and prenatal history data available from the Pediatric Cardiac Genomics Consortium's CHD GENES study (Genetic Network). The frequency of DNVs was compared between subgroups using t test or linear model.

RESULTS

Among 1812 patients with CHD, the number of DNVs per patient was higher with maternal diabetes (76.5 versus 72.1, t test P=3.03×10^-11), but the difference was no longer significant after including parental ages in a linear model (paternal and maternal correction P=0.42). No interaction was observed between diabetes risk and parental age (paternal and maternal interaction P=0.80 and 0.68, respectively). No difference was seen in DNV count per patient based on maternal obesity (72.0 versus 72.2 for maternal body mass index <25 versus maternal body mass index >30, t test P=0.86).

CONCLUSIONS

After accounting for parental age, the offspring of diabetic or obese mothers have no increase in DNVs compared with other children with CHD. These results emphasize the role for other mechanisms in the cause of CHD associated with these prenatal exposures.

REGISTRATION

URL: https://clinicaltrials.gov; NCT01196182.

Evaluation of the association between maternal folic acid supplementation and the risk of congenital heart disease: a systematic review and meta-analysis

Background

Folic acid (FA), as a synthetic form of folate, has been widely used for dietary supplementation in pregnant women. The preventive effect of FA supplementation on the occurrence and recurrence of fetal neural tube defects (NTD) has been confirmed. Incidence of congenital heart diseases (CHD), however, has been parallelly increasing worldwide. The present study aimed to evaluate whether FA supplementation is associated with a decreased risk of CHD.

Methods

We searched the literature using PubMed, Web of Science and Google Scholar, for the peer-reviewed studies which reported CHD and FA and followed with a meta-analysis. The study-specific relative risks were used as summary statistics for the association between maternal FA supplementation and CHD risk. Cochran's Q and I² statistics were used to test for the heterogeneity.

Results

Maternal FA supplementation was found to be associated with a decreased risk of CHD (OR = 0.82, 95% CI: 0.72–0.94). However, the heterogeneity of the association was high (P < 0.001, I² = 92.7%). FA supplementation within 1 month before and after pregnancy correlated positively with CHD (OR 1.10, 95%CI 0.99–1.23), and high-dose FA intake is positively associated with atrial septal defect (OR 1.23, 95%CI 0.64–2.34). Pregnant women with irrational FA use may be at increased risk for CHD.

Conclusions

Data from the present study indicate that the heterogeneity of the association between maternal FA supplementation and CHD is high and suggest that the real relationship between maternal FA supplementation and CHD may need to be further investigated with well-designed clinical studies and biological experiments.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12937-022-00772-2.

Association of polymorphisms of FOLR1 gene and FOLR2 gene and maternal folic acid supplementation with risk of ventricular septal defect: a case-control study

OBJECTIVES

It was the first time to examine the role of maternal polymorphisms of FOLR1 gene and FOLR2 gene, as well as their interactions with maternal folic acid supplementation (FAS), in the risk of ventricular septal defect (VSD).

METHODS

A case-control study was conducted with 385 mothers of VSD infants and 652 controls. The exposures of interest were FAS and FOLR1 gene and FOLR2 gene polymorphisms. The logistic regression model was used for accessing the strength of association.

RESULTS

After controlling for the potential confounders, women who did not utilize folic acid had a substantially higher risk of VSD (aOR = 2.25; 95% CI: 1.48 to 3.43), compared to those who did. We also observed genetic polymorphisms of FOLR1 gene at rs2071010 (GA vs. GG: aOR = 0.63, 95%CI: 0.45 to 0.88) and rs11235462 (AA vs. TT: aOR = 0.53, 95%CI: 0.33 to 0.84), as well as FOLR2 gene at rs651646 (AA vs. TT: aOR = 0.46, 95%CI: 0.30 to 0.70), rs2298444 (CC vs. TT: aOR = 0.58, 95%CI: 0.36 to 0.91) and rs514933 (TC vs. TT: aOR = 0.57, 95%CI: 0.41 to 0.78) were associated with a lower risk of VSD. Furthermore, there was a statistically significant interaction between maternal FAS and genetic polymorphisms at rs514933 on the risk of VSD (FDR_P = 0.015).

CONCLUSIONS

The maternal genetic polymorphisms of the FOLR1 gene and FOLR2 gene, as well as FAS and their interactions, were shown to be significantly associated with the risk of VSD in offspring.

The association between folic acid supplementation and congenital heart defects: Systematic review and meta-analysis

Introduction:

Various trial and epidemiological studies consistently documented the association between maternal folic acid supplementations and neural tube defects. However, existing literatures revealed inconclusive findings about maternal periconceptional folic acid supplementations and the risk of congenital heart defects. Thus, the current systematic review and meta-analysis was aimed to estimate the pooled association between maternal periconceptional folic acid supplementations and congenital heart defects.

Methods:

Electronic searches of PubMed, Web of Science/Scopus, Cochrane library and Google Scholar databases were conducted to access the required studies published up to March 2021. Predetermined eligibility criteria were used for study selections. Data extraction were independently done on excel. STATA version 14 software was used to calculate the pooled effect size with 95% confidence intervals (95% CI) of maternal periconceptional folic acid supplementations on congenital heart defects using the DerSimonian and Laird random effects meta-analysis (random effects model). Statistical heterogeneity was checked using the Cochran Q test (chi-squared statistic), I2 statistic, and by visual inspection of the funnel plot.

Results:

A total of 37 studies of case–control, cohort and randomized controlled trial in nature were included in the review. The finding of the present systematic review and meta-analysis indicated that periconceptional folic acid supplementation significantly decreases the risk of congenital heart defects (risk ratio (RR), 0.79; CI, 0.71, 0.89). Both Cochrane Q test statistic (χ2 = 19.33, p = 0.962) and I2 test statistic (I2 = 0.0%, p = 0.962) did not reveal statistically significant heterogeneity among included studies. In this meta-analysis, traditional funnel plot, Begg’s funnel plot, Egger’s weighted regression (p = 0.13) as well as Begg’s rank correlation statistic (p = 0.676) revealed no evidence of publication bias.

Conclusion:

The present systematic review and meta-analysis found that maternal periconception folic acid supplementation was significantly associated with the risk of congenital heart defects. The risk of congenital heart defects was significantly reduced by 21% among those children of mothers who use periconceptional folic acid supplementations in high-income countries. We recommend that a large prospective study be conducted to investigate the association between maternal periconceptional folic acid supplementation and occurrence of congenital heart defect of various types, especially in the developing countries.

Preconception Dietary Patterns and Associations With IVF Outcomes: An Ongoing Prospective Cohort Study

There is a lack of research on preconception diet and reproductive outcomes conducted in the Chinese population using individual assessment. Between April 2017 and April 2020, 2,796 couples undergoing in vitro fertilization treatment were recruited in this ongoing prospective cohort, and 1,500 eligible couples were included in the final analysis. A validated semi-quantitative food frequency questionnaire was used to evaluate the maternal preconception diet. Other lifestyle factors, including smoking status, psycho-mental status, sleep quality, and physical activity, were also assessed. Five dietary patterns were identified using principal component analysis, namely "Fruits-Vegetables-Dairy-Eggs," "Fish/Seafood-Animal blood," "Tubers-Beans-Cereals," "Puffed food-Candy-Bakery," and "Dried Fruits-Organs-Rice." After adjusting for multiple confounders, we detected that the women who are more inclined to the "Fruits-Vegetables-Dairy-Eggs" pattern and less adherent to the "Tubers-Beans-Cereals" were more likely to achieve normally fertilized eggs and transferable embryos. Regarding pregnancy outcomes, we observed that a lower "Puffed food-Candy-Bakery" score and a higher "Dried fruits-Organs-Rice" score were related to a higher likelihood to achieve biochemical pregnancy. In terms of pregnancy complications, an inverse association between "Fish/Seafood-Animal blood" and hypertensive disorders was observed. We further clustered the dietary patterns based on the proportion of food groups consumed and found that dairy intake was beneficial to embryo quality, while frequent rice consumption was associated with a higher risk of macrosomia. Notably, in the stratified analysis, we observed that the positive relationship between the "Fruit-Dairy-Vegetables-Eggs" score and normal fertilization and the inverse association of the "Fish/Seafood-Animal blood" score with hypertensive disorders during pregnancy were exhibited only among women with body mass index ≥25 kg/m2. In conclusion, pre-treatment diets might be an important target for intervention to achieve a better reproductive outcome.

Roles of Wnt Signaling Pathway and ROR2 Receptor in Embryonic Development: An Update Review Article

The Wnt family is a large class of highly conserved cysteine-rich secretory glycoproteins that play a vital role in various cellular and physiological courses through different signaling pathways during embryogenesis and tissue homeostasis 3. Wnt5a is a secreted glycoprotein that belongs to the noncanonical Wnt family and is involved in a wide range of developmental and tissue homeostasis. A growing body of evidence suggests that Wnt5a affects embryonic development, signaling through various receptors, starting with the activation of β-catenin by Wnt5a. In addition to affecting planar cell polarity and Ca2+ pathways, β-catenin also includes multiple signaling cascades that regulate various cell functions. Secondly, Wnt5a can bind to Ror receptors to mediate noncanonical Wnt signaling and a significant ligand for Ror2 in vertebrates. Consistent with the multiple functions of Wnt5A/Ror2 signaling, Wnt5A knockout mice exhibited various phenotypic defects, including an inability to extend the anterior and posterior axes of the embryo. Numerous essential roles of Wnt5a/Ror2 in development have been demonstrated. Therefore, Ror signaling pathway become a necessary target for diagnosing and treating human diseases. The Wnt5a- Ror2 signaling pathway as a critical factor has attracted extensive attention.

Maternal Periconceptional Folic Acid Supplementation and Risk for Fetal Congenital Heart Defects

OBJECTIVE

To determine the effects of maternal periconceptional supplementation with folic acid or multiple micronutrients containing folic acid on the prevention of fetal congenital heart defects (CHDs).

STUDY DESIGN

Data were drawn from a Prenatal Health Care System and a Birth Defects Surveillance System in a district of Beijing, China. A total of 63 969 singleton births, live or stillborn, 308 CHDs among them, during 2013 to 2018 were included. Associations between different patterns of supplementation and risk for total CHDs or main types of CHDs were evaluated with risk ratios (RRs).

RESULTS

For folic acid or multiple micronutrients containing folic acid users compared with nonusers, the adjusted RRs (ARRs) for total CHDs, critical CHD, and ventricular septal defect (VSD) were 0.60 (95% CI, 0.44-0.83), 0.41 (95% CI, 0.26-0.67), and 0.47 (95% CI, 0.30-0.74), respectively. When we compared multiple micronutrients containing folic acid users with folic acid users, the ARRs were 0.84 (95% CI, 0.66-1.09), 0.64 (95% CI, 0.41-1.00), and 0.94 (95% CI, 0.63-1.41) for total CHDs, critical CHD, and VSD, respectively. We also found that, compared with supplementation initiated after conception, supplementation initiated before conception was associated with a lower risk for CHDs: the ARRs were 0.68 (95% CI, 0.48-0.95) for total CHDs and 0.26 (95% CI, 0.10-0.71) for critical CHD, but 1.08 (95% CI, 0.63-1.83) for VSD.

CONCLUSIONS

Maternal periconceptional supplementation with folic acid or multiple micronutrients containing folic acid seems to decrease the risk for CHDs, especially critical CHD, in offspring. Supplementation confers a greater protective effect when it is initiated before conception. We did not find any difference between folic acid and multiple micronutrients containing folic acid in terms of preventing CHDs.

Ciprofloxacin exposure and adverse pregnancy outcomes: a Danish nationwide cohort study

Objective

To examine the association between maternal exposure to ciprofloxacin and the risk of miscarriage and major malformations.

Design

A nationwide register‐based cohort study.

Setting

Data were obtained from the Medical Birth Registry, the National Hospital Registry, the Danish National Prescription Registry and Statistics Denmark.

Population

Data were collected in the period between 1997 and 2016 and included all registered pregnancies that ended in an elective termination, miscarriage, stillbirth or a live birth. Exposure was defined as redeeming one or more prescriptions of ciprofloxacin.

Methods

Miscarriage was defined as a diagnosis given before 22 weeks without any medical intervention. Major malformations were classified according to EUROCAT 1.4. We matched ciprofloxacin‐exposed pregnancies to unexposed pregnancies on the propensity score in a ratio 1:4. To estimate the hazard ratio (HR) of miscarriage a Cox proportional hazard regression model was used. A log binomial model was used to estimate the relative risk ratio (RR) of major malformations.

Main outcome measures

HR of miscarriage and the RR of major malformations.

Results

A total of 1 650 649 pregnancies were identified. Of these, 10 250 (2050 ciprofloxacin‐exposed) and 6100 (1220 ciprofloxacin‐exposed) were included in the miscarriage and major malformation analysis, respectively. The HR of miscarriage was 0.99 (95% confidence interval [CI] 0.84–1.17). For major malformation, the RR was 1.01 (95% CI 0.72–1.40). For the organ‐specific major malformations and the sensitivity analyses, no significant increased risks were identified.

Conclusion

We demonstrated no association between miscarriage and maternal ciprofloxacin exposure within the first 22 weeks of pregnancy, or between major malformations and maternal exposure during the first trimester.

Tweetable abstract

No association between maternal ciprofloxacin exposure and adverse pregnancy outcomes.

No association between maternal ciprofloxacin exposure and adverse pregnancy outcomes.

Birth prevalence of congenital heart defects in Western Australia, 1990-2016

AIM

To describe the birth prevalence and characteristics of congenital heart defects in a geographically defined Australian population.

METHODS

This descriptive, population-based study examined congenital heart defects in live births, stillbirths and pregnancy terminations ascertained by the Western Australian Register of Developmental Anomalies, 1990-2016. Birth prevalence (per 1000 births) was stratified by severity, known cause, maternal and birth characteristics, and primary diagnosis; and prevalence ratios were calculated for Aboriginal versus non-Aboriginal births. Temporal trends in prevalence, diagnosis age and infant mortality were examined.

RESULTS

For births 1990-2010 (allowing 6 years for complete case ascertainment by 2016), 6419 cases were identified; prevalence was 11.5 per 1000 births (95% confidence interval (CI), 11.2-11.8). Severe defects were ascertained in 2.5 per 1000 births (95% CI 2.4-2.7). Most cases were liveborn (5842, 91.0%), and 28.9% had other birth defects. Prevalence was slightly higher in Aboriginal births (prevalence ratio 1.1; 95% CI 1.0-1.2); and the infant mortality rate more than doubled (13.4% vs. 5.8%, P < 0.001). Prenatal diagnosis increased over time but, in remote areas, was significantly lower for Aboriginal versus non-Aboriginal cases (3.1% vs. 9.3%; P = 0.008). A cause was identified in 920 cases (14.3%), more often for severe defects (347, 24.4%); 63% of known causes were rare diseases. Congenital heart defects associated with fetal alcohol spectrum disorder were much more common in Aboriginal births (prevalence ratio 82; 95% CI 28-239).

CONCLUSIONS

Earlier detection of congenital heart defects and improved survival has occurred over time, although discrepancies between ethnic groups and regions warrant further investigation and strategic action.

Effect of Maternal Prepregnancy/Early-Pregnancy Body Mass Index and Pregnancy Smoking and Alcohol on Congenital Heart Diseases: A Parental Negative Control Study

Background Congenital heart diseases (CHDs) are the most common congenital anomaly. The causes of CHDs are largely unknown. Higher prenatal body mass index (BMI), smoking, and alcohol consumption are associated with increased risk of CHDs. Whether these are causal is unclear. Methods and Results Seven European birth cohorts, including 232 390 offspring (2469 CHD cases [1.1%]), were included. We applied negative exposure paternal control analyses to explore the intrauterine effects of maternal BMI, smoking, and alcohol consumption during pregnancy, on offspring CHDs and CHD severity. We used logistic regression, adjusting for confounders and the other parent's exposure and combined estimates using a fixed-effects meta-analysis. In adjusted analyses, maternal overweight (odds ratio [OR], 1.15 [95% CI, 1.01-1.31]) and obesity (OR, 1.12 [95% CI, 0.93-1.36]), compared with normal weight, were associated with higher odds of CHD, but there was no clear evidence of a linear increase in odds across the whole BMI distribution. Associations of paternal overweight, obesity, and mean BMI were similar to the maternal associations. Maternal pregnancy smoking was associated with higher odds of CHD (OR, 1.11 [95% CI, 0.97-1.25]) but paternal smoking was not (OR, 0.96 [95% CI, 0.85-1.07]). The positive association with maternal smoking appeared to be driven by nonsevere CHD cases (OR, 1.22 [95% CI, 1.04-1.44]). Associations with maternal moderate/heavy pregnancy alcohol consumption were imprecisely estimated (OR, 1.16 [95% CI, 0.52-2.58]) and similar to those for paternal consumption. Conclusions We found evidence of an intrauterine effect for maternal smoking on offspring CHDs, but no evidence for higher maternal BMI or alcohol consumption. Our findings provide further support for the importance of smoking cessation during pregnancy.

Maternal folic acid supplementation mediates the associations between maternal socioeconomic status and congenital heart diseases in offspring

Low maternal socioeconomic status (SES) is considered as a risk factor of congenital heart diseases (CHDs) in offspring. However, the pathways underpinning the SES-CHDs associations are unclear. We assessed if first trimester maternal folic acid supplementation (FAS) is a mediator of the SES-CHDs associations. This case-control study included 8379 CHD cases and 6918 CHD-free controls from 40 participating centers in Guangdong, Southern China, 2004-2016. All fetuses were screened for CHDs using ultrasound and cases were confirmed by echocardiogram. We collected SES and FAS information during face-to-face interview by obstetricians using a structured questionnaire. Low SES was defined as education attainment <12 years, household individual income <3000 Chinese Yuan/person/month or unemployment. FAS referred to at least 0.4 mg of daily folic acid intake over 5 days/week continuously. We used causal mediation analysis to estimate the direct, indirect and proportion mediated by FAS on the SES-CHDs associations adjusted for confounders. Both low maternal income and education were significantly associated with increased risks of CHDs and lower prevalence of FAS. Low maternal FAS prevalence mediated 10% [95%CI:5%,13%] and 3% [95%CI:1%,5%] of the maternal low income-CHDs and the maternal low education-CHDs associations, respectively. In addition, FAS mediated the highest proportion of the associations between income and multiple critical CHDs [46.9%, 95%CI:24.7%,77%] and conotruncal defects [31.5%, 95%CI:17.1%,52.0%], respectively. Maternal FAS partially mediated the SES-CHDs associations, especially among the most critical and common CHDs. Promoting FAS in low SES women of childbearing age may be a feasible intervention to help prevent CHDs.

Degree of pregnancy planning and recommended pregnancy planning behavior among women with and without chronic medical conditions - A large hospital-based cross-sectional study

INTRODUCTION

Pregnancy planning allows women to engage in pregnancy planning behaviors to optimize health status in the preconception period. Women with chronic medical conditions have a higher risk for adverse pregnancy outcomes and therefore preconception care is recommended. The aim was to compare pregnancy planning among women with and without chronic medical conditions, and to assess adherence to the recommended pregnancy planning behaviors on folic acid intake, physical activity and abstention from smoking and alcohol, among women with and without chronic medical conditions stratified by pregnancy planning.

MATERIAL AND METHODS

A cross-sectional study with data from 28 794 pregnancies. Pregnancy planning was measured with the Swedish Pregnancy Planning Scale. Multiple Poisson regression with robust variance estimates was used to assess the associations between chronic medical condition (yes/no and main categories) and pregnancy planning, and chronic medical condition status and pregnancy planning behaviors stratified by pregnancy planning.

RESULTS

In the study population, 74% reported high degree of pregnancy planning, and 22% had one or more chronic medical conditions. We found no overall association between chronic medical condition and pregnancy planning (adjusted rate ratio [RR] 1.00, 95% confidence interval [CI] 0.98-1.01). However, women with type 2 diabetes and mental illness were significantly less likely to plan their pregnancies than women without these conditions (aRR 0.73, 95% CI 0.61-0.88; aRR 0.91, 95% CI 0.87-0.96, respectively). Women with chronic medical conditions were more likely to adhere to the recommended planning behaviors; intake of folic acid, abstention from alcohol prior to pregnancy and no binge drinking in early pregnancy.

CONCLUSIONS

Overall, pregnancies were highly planned. Women with chronic medical conditions did not show a higher degree of pregnancy planning than women without chronic medical conditions but were, however. more likely to adhere to the generally recommended pregnancy planning behaviors (ie intake of folic acid and abstention from alcohol intake). Only women with mental illness and type 2 diabetes reported a lower degree of pregnancy planning. It is important that we continuously address pregnancy planning and planning behaviors for both women with and women without chronic medical conditions, especially women with type 2 diabetes and mental illness.

Factors Associated With Neural Tube Defects Among Newborns Delivered at Debre Berhan Specialized Hospital, North Eastern Ethiopia, 2021. Case-Control Study

BACKGROUND

Neural tube defects are severe congenital malformations secondary to an abnormal closure of the neural tube between third and fourth weeks of gestational ages. Neural tube defects affect birth outcomes worldwide, with an occurrence of 18.6 per 10,000 live births. In addition, neural tube defects are associated with considerable mortality, morbidity, disability, and socio-economical cost.

OBJECTIVE

To identify factors associated with neural tube defects among newborns delivered at Debre Berhan Comprehensive Specialized Hospital, 2021.

METHODS

Facility-based case-control study design was conducted among 381 (127 cases and 254 controls) newborns delivered from June 2019 to June 2021 at Debre Berhan Specialized Hospital. Consecutive and systematic random sampling techniques were used to select cases and controls, respectively. Data were collected using semi-structured checklists. Finally, data were entered using Epidata version 4.2.1 and analyzed using SPSS version 25. In the bivariable logistic regression model, factors with a p < 0.20 were entered into multivariable logistic regressions. Statistical significance was declared at a p < 0.05.

RESULT

In this study, 381 newborns (127 cases and 254 controls) participated with a response rate of 100%. In the logistic regression model, mothers who took medication during pregnancy [AOR 1.83 (95% CI 1.08-3.08)], mothers who did not take a balanced diet during pregnancy [AOR 13.46 (95% CI 7.83-23.13)], and mothers who did not take folic acid before and during the first trimester of pregnancy [AOR 1.71 (95% CI 1.01-2.94)] were significantly associated with neural tube defect.

CONCLUSION AND RECOMMENDATION

Mothers who took medication during pregnancy, mothers who did not take balanced diets during pregnancy, and mothers who did not take folic acid during pregnancy were the significant factors of neural tube defects. Health care professionals should focus on maternal safe drug prescription, maternal folate intake, and a balanced diet before and during pregnancy.

Maternal B-vitamin intake and B-vitamin supplementation during pregnancy in relation to neonatal congenital heart defects: a case-control study with propensity score matching

BACKGROUND/OBJECTIVES

The effect of dietary folate intake or folic acid (FA) supplementation during pregnancy on neonatal congenital heart defects (CHDs) remains inconclusive. There are limited data about non-folate-B-vitamin intake and the risk of CHDs. Furthermore, few studies have investigated dietary B-vitamin intake and B-vitamin supplement use simultaneously in relation to the risk of CHDs. This study aimed to explore the associations between maternal folate, vitamin B₆, and vitamin B₁₂ intake (dietary intake, total intake from diet and supplements); B-vitamin supplement use during pregnancy; and the risk of CHDs using the propensity score matching (PSM) method.

METHODS

We conducted a case-control study and included 760 cases and 1600 controls in Shaanxi Province, China. Diet, supplement use and other information were collected through a questionnaire interview. By using the 1:2 ratio PSM method, 396 cases were matched with 792 controls. Conditional logistic regression was used to investigate the associations between maternal B-vitamin intake and supplement use during pregnancy and CHDs.

RESULTS

Higher maternal dietary and total intake of folate and vitamin B₁₂ were associated with reduced risk of CHDs, and the tests for linear trend were significant. Compared with non-users, maternal FA + VB₆ + VB₁₂ containing supplement use during pregnancy (OR 0.61, 95%CI 0.40-0.94), FA supplement use during pregnancy (OR 0.70, 95%CI 0.50-0.98) and in the first trimester (OR 0.62, 95%CI 0.46-0.85) were associated with a lower risk of CHDs.

CONCLUSIONS

The findings of this study suggest that a higher intake of folate and vitamin B₁₂ during pregnancy reduces the risk of CHDs.

Genetic predisposition to the development of congenital heart diseases: Role of xenobiotic biotransformation genes

Congenital heart diseases are one of the most common multi-factorial fetal abnormalities caused by a complex of endo- and exogenous factors. It is known that mutations in xenobiotic biotransformation genes can be associated with the pathogenesis of congenital heart diseases. In the presented research, 131 children with congenital heart diseases and 101 women having children with this pathology were included in the study group. In control group, 103 healthy children and their mothers were included. Single-nucleotide polymorphisms in the xenobiotic biotransformation genes CYP1A1 (rs1048943), CYP1A2 (rs762551), GSTP1 (rs6591256, rs1871042 and rs17593068) were detected by the real-time polymerase chain reaction. Gene-gene interactions were determined using the Multifactor Dimensionality Reduction method. We obtained no difference in the frequency of CYP1A1, CYP1A2 and GSTP1 between the study and control groups. At the same time, the genetic combinations GSTP1 (rs6591256)-GSTP1 (rs1871042) and GSTP1 (rs6591256)-GSTP1 (rs1871042)-CYP1A1 (rs1048943) in women; and GSTP1 (rs1793068)-GSTP1 (rs6591256)-GSTP1 (rs1871042)-CYP1A1 (rs1048943)-CYP1A2 (rs762551) in children contribute to the pathogenesis of congenital heart diseases.

The effect of maternal pre-/early-pregnancy BMI and pregnancy smoking and alcohol on congenital heart diseases: a parental negative control study

BACKGROUND

Congenital heart diseases (CHDs) are the most common congenital anomaly. The causes of CHDs are largely unknown. Higher prenatal body mass index (BMI), smoking and alcohol consumption are associated with increased risk of CHDs. Whether these are causal is unclear.

METHODS AND RESULTS

Seven European birth cohorts including 232,390 offspring (2,469 CHD cases [1.1%]) were included. We applied negative exposure paternal control analyses to explore the intrauterine effects of maternal BMI, smoking and alcohol consumption during pregnancy, on offspring CHDs and CHD severity. We used logistic regression and combined estimates using a fixed-effects meta-analysis. Analyses of BMI categories resulted in similar increased odds of CHD in overweight (mothers OR: 1.15 (1.01, 1.31) and fathers 1.10 (0.96, 1.27)) and obesity (mothers OR: 1.12 (0.93, 1.36) and fathers 1.16 (0.90, 1.50)). The association of mean BMI with CHD was null. Maternal smoking was associated with increased odds of CHD (OR: 1.11 (0.97, 1.25)) but paternal smoking was not (OR: 0.96 (0.85, 1.07)). The difference increased when removing offspring with genetic/chromosomal defects (mothers OR: 1.15 (1.01, 1.32) and fathers 0.93 (0.83, 1.05)). The positive association with maternal pregnancy smoking appeared to be driven by non-severe CHD cases (OR: 1.22 (1.04, 1.44)). Associations with maternal (OR: 1.16 (0.52, 2.58)) and paternal (OR: 1.23 (0.74, 2.06)) moderate/heavy pregnancy alcohol consumption were similar.

CONCLUSIONS

We found evidence of an intrauterine effect for maternal smoking on offspring CHDs, but no evidence for higher maternal BMI or alcohol consumption. Our findings provide further support for why smoking cessation is important during pregnancy.

Determinants of Neural Tube Defects among Newborns in Amhara Region, Ethiopia: A Case-Control Study

BACKGROUND

Worldwide, an estimated 300,000 neonates are born with neural tube defects (NTDs) each year. However, NTDs are underreported in Ethiopia though it causes substantial mortality, morbidity, disability, and psychological and economic cost in the country. Moreover, the factors attributed to NTDs were not addressed. Hence, this study intended to identify the determinants of neural tube defects in Amhara Region, Ethiopia.

METHODS

A case-control study design was conducted among 400 newborns (133 cases and 267 controls) who were born at randomly selected public hospitals. Cases were identified using the physician diagnosis of confirmed NTDs, and the two consecutive controls were selected using a simple random sampling technique. The data analysis was done using Stata 14.0. Variables with p value < 0.25 in the bivariate analysis were entered into the multivariable logistic regression model, and a corresponding 95% confidence interval was used to identify the predictors of NTDs.

RESULTS

In this study, fifty percent (48%) of the cases were contributed by anencephaly. After controlling the covariates, living in rural areas (AOR = 1.78: 95% CI 1.02, 3.11), being illiterate (AOR = 1.81: 95% CI 1.07, 4.61), being female newborn (AOR = 1.95: 95% CI 1.09, 3.50), having no ANC follow-up (AOR = 1.93: 95% CI 1.17, 5.04), and having a previous history of NTDs (AOR = 4.39: 95% CI 2.42, 7.96) were the risk factors for NTDs. However, being supplemented with folic acid or multivitamins before or during pregnancy (AOR = 0.37: 95% CI 0.21, 0.65), never having taken any substance during pregnancy (AOR = 0.42: 95% CI 0.21, 0.88), and being free from medical illnesses during pregnancy (AOR = 0.27: 95% CI 0.11, 0.69) were the protective factors of NTDs.

CONCLUSION

The study revealed different factors associated with NTDs among newborns in the region. Therefore, comprehensive preventive strategies focused on identified risk factors are needed at regional and national levels.

First-Trimester Maternal Folic Acid Supplementation Reduced Risks of Severe and Most Congenital Heart Diseases in Offspring: A Large Case-Control Study

Background Maternal folic acid supplementation (FAS) reduces the risk of neural tube defects in offspring. However, its effect on congenital heart disease (CHDs), especially on the severe ones remains uncertain. This study aimed to assess the individual and joint effect of first-trimester maternal FAS and multivitamin use on CHDs in offspring. Methods and Results This is a case-control study including 8379 confirmed CHD cases and 6918 controls from 40 healthcare centers of 21 cities in Guangdong Province, China. Adjusted odds ratios (aORs) of FAS and multivitamin use between CHD cases (overall and specific CHD phenotypes) and controls were calculated by controlling for parental confounders. The multiplicative interaction effect of FAS and multivitamin use on CHDs was estimated. A significantly protective association was detected between first-trimester maternal FAS and CHDs among offspring (aOR, 0.69; 95% CI, 0.62-0.76), but not for multivitamin use alone (aOR, 1.42; 95% CI, 0.73-2.78). There was no interaction between FAS and multivitamin use on CHDs (P=0.292). Most CHD phenotypes benefited from FAS (aORs ranged from 0.03-0.85), especially the most severe categories (ie, multiple critical CHDs [aOR, 0.16; 95% CI, 0.12-0.22]) and phenotypes (ie, single ventricle [aOR, 0.03; 95% CI, 0.004-0.21]). Conclusions First-trimester maternal FAS, but not multivitamin use, was substantially associated with lower risk of CHDs, and the association was strongest for the most severe CHD phenotypes. We recommend that women of childbearing age should supplement with folic acid as early as possible, ensuring coverage of the critical window for fetal heart development to prevent CHDs.

Association between preconception paternal smoking and birth defects in offspring: evidence from the database of the National Free Preconception Health Examination Project in China

OBJECTIVE

To clarify whether preconception paternal smoking has any adverse effects on the offspring.

DESIGN

Prospective, population-based study.

SETTING

Preconception registry data from the National Free Preconception Health Examination Project.

POPULATION OR SAMPLE

Couples planning pregnancy, with complete information on preconception paternal smoking behaviour and pregnancy outcomes.

METHODS

The effect of questionnaire-based paternal smoking behaviour during preconception and pregnancy was assessed via logistic regression. Additionally, we performed a 1:1 case-control (birth defects versus normal pregnancy) analysis, matched for maternal province, folic acid supplementation and paternal alcohol consumption.

MAIN OUTCOME MEASURES

Risk of birth defects in offspring.

RESULTS

In total, 566 439 couples with complete information on preconception paternal smoking behaviour and pregnancy outcomes were enrolled. The preconception paternal smoking rate was 28.7% (162 482) overall: 8.7% (49 303) stopped smoking, 13.3% (75 517) decreased their smoking, and 6.6% (37 662) continued smoking during early pregnancy. The risk of birth defects was higher in the continued-smoking (P < .000, odds ratio [OR] 1.87, 95% CI 1.36-2.56) and decreased-smoking groups (P = .007, OR 1.41, 95% CI 1.10-1.82). In the case-control analysis, infants whose fathers stopped (P = .003, OR 0.32, 95% CI 0.15-0.67) or decreased smoking (P = .000, OR 0.25, 95% CI 0.13-0.49) were at lower risk of congenital heart diseases, limb abnormalities, digestive tract anomalies and neural tube defects than those whose fathers continued smoking.

CONCLUSION

Preconception paternal smoking may be associated with congenital heart diseases, limb abnormalities and neural tube defects in the offspring. Changes in smoking behaviour may reduce this risk.

TWEETABLE ABSTRACT

This study suggests that preconception paternal smoking is associated with birth defects in offspring. Changes in smoking behaviour may reduce this risk.

Maternal use of folic acid and multivitamin supplements and infant risk of birth defects in Norway, 1999-2013

The association between folic acid supplementation and birth defects other than neural tube defects (NTD) remains unclear. We used a log-binomial regression model to investigate if periconceptional folic acid and/or multivitamin use was associated with birth defects in Norway with prospectively collected data from the Medical Birth Registry of Norway (MBRN) during 1999-2013. We used the European Surveillance of Congenital Anomalies (EUROCAT) classification system to define eleven organ-specific major birth defect groups (nervous system, eye, ear-face-neck, cardiovascular system, respiratory system, oral clefts, digestive system, abdominal wall, urinary system, genital organs and limb), with additional subgroups. Fetuses or infants whose mothers used folic acid and/or multivitamin supplements before and during pregnancy were classified as exposed. During the years 1999-2013, 888 294 (99·0 %) live-born infants, 6633 (0·7 %) stillborn infants and 2135 (0·2 %) fetuses from terminated pregnancies due to fetal anomalies were registered in the MBRN. Among the live- and stillborn infants of women who used vitamin supplements compared with infants of non-users, the adjusted relative risk (aRR) was 0·94 (95 % CI 0·91, 0·98) for total birth defects (n 18 382). Supplement use was associated with reduced risk of abdominal wall defects (aRR 0·58; 95 % CI 0·42, 0·80, n 377), genital organ defects (aRR 0·81; 95 % CI 0·72, 0·91, n 2299) and limb defects (aRR 0·81; 95 % CI 0·74, 0·90, n 3409). Protective associations were also suggested for NTD, respiratory system defects and digestive system defects although CI included the null value of 1. During the full study period, statistically significant associations between supplement use and defects in the eye, ear-face-neck, heart or oral clefts were not observed.

Research into the intervention effect of folic acid on arsenic-induced heart abnormalities in fetal rats during the periconception period

BACKGROUND

The incidence of CHD is the highest among birth defects and is increasing year to year. CHD seriously harms the health of infants and young children and presents a large economic burden to families and society. The pathogenesis of CHD and preventive measures are the focus of current research. Our research aimed to explore the intervention effect of folic acid on heart abnormalities resulting from sodium arsenic (NaAsO2) exposure during the periconception period.

METHODS

Sixty 35-day-old female SD rats were randomly divided into 5 groups with 12 rats in each group. Group A was the control group. The rats were given distilled water and ordinary chow. The rats in group B were given distilled water containing 75 mg/L NaAsO2 and ordinary chow. The rats in groups C, D, and E were given distilled water containing 75 mg/L NaAsO2 and chow containing 0.53 mg/kg, 5.3 mg/kg, and 10.6 mg/kg folic acid, respectively. The general condition of the embryos and the histopathology of the embryonic hearts were examined. The acetylation levels of histone H3K9 in heart tissues and the expression levels of Mef2C (which is related to heart development) were observed.

RESULTS

The embryo weight and placental weight of groups B-E were significantly lower than those of group A (P < 0.05). The heart malformation rate of the fetal rats in groups B-E was significantly higher than that of the fetal rats in group A (P < 0.05). We found that the level of H3K9 acetylation in fetal rat cardiomyocytes in groups B-E was significantly higher than that in group A (P < 0.05) and that the level of H3K9 acetylation in groups C-E was lower than that in group B (P < 0.05). The mRNA level of Mef2C in fetal rat cardiomyocytes in group B-E was significantly higher than that in group A (P < 0.05), and the mRNA level of Mef2C in groups C-E was significantly lower than that in group B (P < 0.05).

CONCLUSION

Supplementation with folic acid during the periconception period can interfere with the toxic effects of arsenic on the heart. The mechanism may be that lowering the acetylation levels of histone H3K9 in heart tissues leads to decreased expression levels of Mef2C, which may play a protective role in heart development in fetal rats.

Environmental Risk Factors for Congenital Heart Disease

Congenital heart disease (CHD) has many forms and a wide range of causes. Clinically, it is important to understand the causes. This allows estimation of recurrence rate, guides treatment options, and may also be used to formulate public health advice to reduce the population prevalence of CHD. The recent advent of sophisticated genetic and genomic methods has led to the identification of more than 100 genes associated with CHD. However, despite these great strides, to date only one-third of CHD cases have been shown to have a simple genetic cause. This is because CHD can also be caused by oligogenic factors, environmental factors, and/or gene-environment interaction. Although solid evidence for environmental causes of CHD have been available for almost 80 years, it is only very recently that the molecular mechanisms for these risk factors have begun to be investigated. In this review, we describe the most important environmental CHD risk factors, and what is known about how they cause CHD.

Congenital heart diseases: genetics, non-inherited risk factors, and signaling pathways

Background

Congenital heart diseases (CHDs) are the most common congenital anomalies with an estimated prevalence of 8 in 1000 live births. CHDs occur as a result of abnormal embryogenesis of the heart. Congenital heart diseases are associated with significant mortality and morbidity. The damage of the heart is irreversible due to a lack of regeneration potential, and usually, the patients may require surgical intervention. Studying the developmental biology of the heart is essential not only in understanding the mechanisms and pathogenesis of congenital heart diseases but also in providing us with insight towards developing new preventive and treatment methods.

Main body

The etiology of congenital heart diseases is still elusive. Both genetic and environmental factors have been implicated to play a role in the pathogenesis of the diseases. Recently, cardiac transcription factors, cardiac-specific genes, and signaling pathways, which are responsible for early cardiac morphogenesis have been extensively studied in both human and animal experiments but leave much to be desired. The discovery of novel genetic methods such as next generation sequencing and chromosomal microarrays have led to further study the genes, non-coding RNAs and subtle chromosomal changes, elucidating their implications to the etiology of congenital heart diseases. Studies have also implicated non-hereditary risk factors such as rubella infection, teratogens, maternal age, diabetes mellitus, and abnormal hemodynamics in causing CHDs.

These etiological factors raise questions on multifactorial etiology of CHDs. It is therefore important to endeavor in research based on finding the causes of CHDs. Finding causative factors will enable us to plan intervention strategies and mitigate the consequences associated with CHDs. This review, therefore, puts forward the genetic and non-genetic causes of congenital heart diseases. Besides, it discusses crucial signaling pathways which are involved in early cardiac morphogenesis. Consequently, we aim to consolidate our knowledge on multifactorial causes of CHDs so as to pave a way for further research regarding CHDs.

Conclusion

The multifactorial etiology of congenital heart diseases gives us a challenge to explicitly establishing specific causative factors and therefore plan intervention strategies. More well-designed studies and the use of novel genetic technologies could be the way through the discovery of etiological factors implicated in the pathogenesis of congenital heart diseases.

Association Between Maternal Folic Acid Supplementation and Congenital Heart Defects in Offspring in Birth Cohorts From Denmark and Norway

Background Evidence linking individual-level maternal folic acid supplementation to offspring risk of congenital heart defects is lacking. We investigated whether folic acid supplementation in early pregnancy reduces offspring risk of heart defects in 2 large birth cohort studies. Methods and Results Women recruited in early pregnancy within the DNBC (Danish National Birth Cohort), 1996-2003, and MoBa (Norwegian Mother and Child Cohort Study), 2000-2009, were followed until delivery. Information on periconceptional intake of folic acid and other supplements was linked with information on heart defects from national registers. Among 197 123 births, we identified 2247 individuals with heart defects (114/10 000). Periconceptional (4 weeks before through 8 weeks after conception) use of folic acid plus other supplements (54.8%), folic acid only (12.2%), and non-folic acid supplements (5.0%) were compared with no supplement use (28.0%); the adjusted relative risks of heart defects were 0.99 (95% CI, 0.80-1.22), 1.08 (95% CI , 0.93-1.25), and 1.07 (95% CI , 0.97-1.19), respectively. For initiation of folic acid in the preconception period weeks -4 to -1 (33.7%) and the postconception periods 0 to 4 weeks (15.5%), 5 to 8 weeks (17.8%), and 9 to 12 weeks (4.6%), compared with no or late folic acid intake (29.1%), relative risks of heart defect were 1.11 (95% CI , 1.00-1.25), 1.09 (95% CI , 0.95-1.25), 0.98 (95% CI , 0.86-1.12), and 0.97 (95% CI , 0.78-1.20), respectively. Relative risks of severe defects, conotruncal defects, and septal defects showed similar results. Conclusions Folic acid was not associated with offspring risk of heart defects, including severe defects, conotruncal defects, or septal defects.