Prevention of neural-tube defects with folic acid in China. China-U.S. Collaborative Project for Neural Tube Defect Prevention

Optical genome mapping identifies rare structural variants in neural tube defects

Neural tube defects (NTDs) are the most common birth defects of the central nervous system and occur as either isolated malformations or accompanied by anomalies of other systems. The genetic basis of NTDs remains poorly understood using karyotyping, chromosomal microarray, and short-read sequencing, with only a limited number of pathogenic variants identified. Collectively, these technologies may fail to detect rare structural variants (SVs) in the genome, which may cause these birth defects. Therefore, optical genome mapping (OGM) was applied to investigate 104 NTD cases, of which 74 were isolated NTDs and 30 were NTDs with other malformations. A stepwise approach was undertaken to ascertain candidate variants using population and internal databases and performing parental studies when possible. This analysis identifies diagnostic findings in 8% of cases (8/104) and candidate findings in an additional 22% of cases (23/104). Of the candidate findings, 9% of cases (9/104) have SVs impacting genes associated with NTDs in mouse, and 13% of cases (14/104) have SVs impacting genes implicated in the neural tube development pathways. This study identifies RMND5A, HNRNPC, FOXD4, and RBBP4 as strong candidate genes associated with NTDs, and expands the phenotypic spectrum of AMER1 and TGIF1 to include NTDs. This study constitutes the first systematic investigation of SVs using OGM to elucidate the genetic determinants of NTDs. The data provide key insights into the pathogenesis of NTDs and demonstrate the contribution of SVs in the genome to these birth defects.

Association between gestational weight change trajectories and perinatal outcomes in twin pregnancies in China

OBJECTIVE

This study aimed to identify gestational weight change trajectories and examine their association with perinatal outcomes.

METHODS

Prenatal and delivery records of 3393 twin pregnancies were obtained from the China-US Collaborative Project for Neural Tube Defects Prevention, a large population-based cohort study. Generalized gestational weight gain (GWG) was calculated by dividing the total GWG by the length of gestation in weeks and multiplying by 37 weeks. Latent class growth modeling (LCGM) was used to identify GWG patterns. Multivariable logistic regression and generalized estimating equations (GEE) were used to analyze the associations between GWG trajectories and perinatal outcomes. The included adverse perinatal outcomes were preterm birth, low birth weight (LBW), small for gestational age (SGA), and large for gestational age (LGA).

RESULTS

The mean ± SD of GWG for underweight women was 17.87 ± 5.67 kg, 16.76 ± 6.22 kg for normal weight, 14.34 ± 6.60 kg for overweight, and 14.27 ± 4.94 kg for obese. Three gestational weight change trajectory groups were identified: low-increase (32.36%), moderate-increase (56.26%), and high-increase (11.38%). Compared to the moderate-increase group, the high-increase group showed a reduced risk of LBW (aOR 0.68, 95%CI 0.56, 0.83), and SGA (aOR 0.49, 95%CI 0.40, 0.60) but an increased risk of LGA (aOR 2.23, 95%CI 1.48, 3.35). No significant change was observed in the risk of preterm birth in the high-increase group. The low-increase group had a higher risk of preterm birth (aOR 1.66 95%CI 1.42, 1.94), LBW (aOR 2.44 95%CI 2.13,2.80), and SGA (aOR 1.32 95%CI 1.16, 1.51), with no significant difference in the risk of LGA (aOR 1.11 95%CI 0.78,1.58).

CONCLUSIONS

Distinct patterns of GWG in twin pregnancies are associated with varying risks of adverse perinatal outcomes. These findings highlight the importance of monitoring and managing GWG in twin pregnancies.

Tetrahydrofolic acid accelerates amyloid fibrillization, decreases cytotoxic oligomers and suppresses their toxicity

Soluble cytotoxic oligomers produced during the fibrillation of both α-synuclein (αS) and amyloid-β protein (Aβ) are key pathogenic factors in Parkinson's disease (PD) and Alzheimer's disease (AD). Reducing toxic oligomers by regulating the aggregation process of αS and Aβ is an important strategy for the treatment of PD and AD. Herein, tetrahydrofolic acid (THF) is found to accelerate amyloid fibrillization, decreases cytotoxic oligomers and suppresses their toxicity. Thioflavin T and atomic force microscopy assays results showed that THF was able to accelerate the formation of dense fibrils from αS and Aβ in a dose-dependent manner. Strikingly, this was accompanied by a reduction in the abundance of toxic oligomers, and these results were confirmed by DB. Meanwhile, MTT and FDA/PI assays demonstrated that THF-induced accelerated fibril formation was accompanied by a reduction in αS- and Aβ-induced cytotoxicity. In addition, the lifespan of genetically modified αS and Aβ expressing C. elegans was extended by feeding THF, although plaque deposits of αS and Aβ increased. These findings suggest that THF enhances the conversion of αS and Aβ oligomers into less toxic fibrils and is a potential therapeutic agent for PD and AD.

A Randomized Crossover Trial of Acceptability of Quadruple-Fortified Salt in Women and their Households in Southern India

BACKGROUND

Double-fortified salt (DFS; iron, iodine) improved iron status in randomized trials and was incorporated into India's social safety net programs, suggesting opportunities to address other micronutrient deficiencies.

OBJECTIVES

To evaluate the acceptability of quadruple-fortified salt (QFS; iron, iodine, folic acid, and vitamin B12) in women and their households, using a randomized crossover trial design and triangle tests.

METHODS

Women 18-49 y (n = 77) and their households were randomly assigned to receive QFS or DFS in a randomized crossover design over a 3-wk period (week 1: QFS/DFS, week 2: iodized salt, week 3: DFS/QFS). Each week, participants completed a 9-point hedonic questionnaire (1 = dislike extremely to 9 = like extremely) to evaluate 5 sensory domains (color, odor, taste, texture, and overall acceptability) of the intervention, and the remaining salt was weighed using a digital scale. Triangle tests were conducted among women to evaluate sensory discrimination of salt consumed in rice dishes prepared using standardized recipes. Mixed models were used to examine hedonic ratings and salt use; salt type, sequence, and period were included as fixed effects, and household was included as a random effect. Binomial tests were used to evaluate sensory discrimination of salt type in triangle tests.

RESULTS

Mean hedonic ratings for most of the 5 sensory domains were ≥7 (like moderately) and did not differ by salt type [overall acceptability mean (SD): QFS: 7.8 (0.7) compared with DFS: 7.7 (1.2); P = 0.68]. Household salt use (weighed) did not differ by salt type. During the 3-wk intervention period, weighed salt use and hedonic ratings significantly increased, indicating a period effect independent of salt type or sequence. In triangle tests, rice samples prepared with QFS, DFS, or iodized salt were not distinguishable.

CONCLUSIONS

Acceptability of QFS was high, based on individual hedonic ratings and weighed household salt use. Rice dishes prepared with DFS, QFS, and iodized salt were not distinguishable. Findings informed the design of a randomized trial of QFS in this population. This trial was registered at clinicaltrials.gov as NCT03853304 and CTRI/2024/04/066208.

The current state of Spina Bifida in low- and middle-income countries: where does Africa stand?

Spina bifida is a congenital neural tube defect that results in abnormal development of the spine and central nervous system. Infants born with this condition face a range of physical disabilities and associated complications. Although the global burden has declined in recent decades due to folic acid fortification and prenatal screening, spina bifida remains a significant public health challenge in many low- and middle-income countries (LMICs), particularly in sub-Saharan Africa. This research aimed to comprehensively assess the current epidemiological trends, clinical management practices, and socioeconomic impacts of spina bifida across African LMICs. Through a systematic analytical search of published literature from major medical databases covering the years 2000-2023, relevant data were extracted on the prevalence, risk factors, clinical presentations, treatment modalities, outcomes, and contextual barriers faced in preventing and caring for spina bifida in these settings. The findings were analyzed and synthesized to provide an overview of the contemporary landscape. The findings highlight the need for collaborative efforts between governments, healthcare providers, nongovernmental organizations, and international stakeholders to address the multifaceted challenges posed by spina bifida in LMICs, particularly within the African continent, and to promote equitable access to comprehensive care and support for affected individuals and their families.

Genome-Wide Association Study Identifies Genetic Polymorphisms for Folate-Related Biomarkers in Chinese Preconception Women

BACKGROUND

Single-nucleotide polymorphism (SNP) allele frequencies, dietary habits, and folate status and their associations vary across ethnic populations. Little is known about the SNPs accounting for variations of folate-related biomarkers for Chinese preparing-for-pregnant females.

OBJECTIVES

We aimed to identify SNPs contributing to RBC and serum folate, vitamin B-12, and homocysteine concentrations in Chinese female preconception population.

METHODS

A genome-wide association study was conducted on 1000 randomly selected preconception Chinese women from the Shanghai Preconception Cohort. SNPs were genotyped using Illumina chips, and associations with biomarkers were assessed using simple linear regression models under the assumption of an additive genetic model. Genome-wide significance was considered at P < 10-7.

RESULTS

The MTHFR rs1801133 was the major genetic coding variant contributing to RBC folate, serum folate, and homocysteine concentrations (P = 2.28 × 10-16; P = 8.85 × 10-8, and P = 2.46 × 10-13, repsectively). It is associated with increased RBC folate (β: 0.154 per additional risk allele after log transform), decreased serum folate (β: -0.951 per additional risk allele), and increased serum homocysteine concentrations (β: 1.153 per additional risk allele). The predominant SNP associated with serum folate was rs147162222 in NTRK2 (P = 2.55 × 10-8), although that associated with homocysteine was rs77025184 located between PDE7B and LINC00271 (P = 4.91 × 10-17). For vitamin B-12, FUT2 rs1047781 was the dominant genetic variant (P = 1.59 × 10-10). The numbers of signals with a P value of <10-7 for RBC folate, serum folate, vitamin B-12, and homocysteine were 12, 18, 8, and 614, respectively.

CONCLUSIONS

This study represents the first genome-wide association study focusing on folate-related biomarkers in a Chinese preparing-for-pregnant female population. The contributions of dominent SNPs to each biomarker are partly different from other populations. The rs1801133 (C677T) in MTHFR is the predominant genetic variant contributing to RBC folate and rs1047781 (A385T) in FUT2 as the primary one explaining vitamin B-12. Notably, the intronic rs147162222 and noncoding rs77025184 are the predominant SNPs for serum folate and homocysteine, respectively.

Cycloleucine induces neural tube defects by reducing Pax3 expression and impairing the balance of proliferation and apoptosis in early neurulation

S-adenosylmethionine (SAM) plays a critical role in the development of neural tube defects (NTDs). Studies have shown that the paired box 3 (Pax3) gene is involved in neural tube closure. However, the exact mechanism between Pax3 and NTDs induced by SAM deficiency remains unclear. Here, The NTD mouse model was induced using cycloleucine (CL), an inhibitor of SAM biosynthesis, to determine the effect of Pax3 on NTDs. The effect of CL on NTD occurrence was assessed by 5-ethynyl-2'-deoxyuridine (EdU) staining, immunohistochemistry, terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL), quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR), and Western blot in NTD embryonic brain tissues and immortalized hippocampal neuron cells (HT-22). A high incidence of NTDs was observed when CL was administered at a dose of 200 mg/kg body weight. The levels of SAM and Pax3 were significantly reduced in NTD embryonic brain tissues and HT-22 cells after CL exposure. Decreased proliferation and excessive apoptosis were observed in neuroepithelial cells of NTD embryos and HT-22 cells under SAM deficiency, but these effects were reversed by overexpression of Pax3. These results suggest that decreased expression of Pax3 impairs the dynamic balance between cellular proliferation and apoptosis, contributing to NTDs induced by SAM deficiency, which would provide new insights for clarifying the underlying mechanism of NTDs.

Protocol for a community-based, household-randomised, dose-response trial to assess the acceptability, nutritional effects and safety of double-fortified salt containing iodine and folic acid compared with iodised salt among non-pregnant Ethiopian women of reproductive age (DFS-IoFA)

INTRODUCTION

The prevalence of neural tube defects (NTDs) is higher in Ethiopia than most other countries, and ~84% of Ethiopian women of reproductive age (WRA) have folate insufficiency, a major risk factor for NTDs. Salt fortification with folic acid is a potential strategy to improve women's folate status, but data are needed on the acceptability, nutritional impact and safety of folic acid fortification of iodised salt.

METHODS AND ANALYSIS

The study is designed as a community-based, household-randomised, dose-response trial. A total of 360 non-pregnant WRA 18-49 years of age will be randomly assigned to one of three intervention arms: (1) iodised salt fortified with 30 ppm folic acid to provide ~200 µg folic acid/day; (2) iodised salt fortified with 90 ppm folic acid to provide ~600 µg folic acid/day; or (3) iodised salt (comparator). The preweighed salts will be delivered to participants' homes biweekly for 26 weeks; unused salt will be collected and weighed. Fasting, venous blood samples will be collected at baseline, end line and a randomly assigned intermediate time point for assessment of folate, iodine, vitamin B12 and other micronutrient status biomarkers. Women's dietary intakes, including discretionary salt consumption, will be measured using weighed food records; 24-hour urine specimens will be analysed for sodium and iodine excretion. Primary outcomes are women's consumption of study salts, change in biomarkers of folate and iodine status and prevalence of adverse events. Results will be analysed using analysis of covariance models to estimate group mean differences for continuous outcomes, controlling for baseline measurements, and log-binomial or modified Poisson regressions for categorical outcomes. Prespecified effect modifications will be explored.

ETHICS AND DISSEMINATION

The study has been approved by the Ethiopian Public Health Institute's Institutional Review Board, and the protocol has been registered with ClinicalTrials.gov (registration number NCT06223854). Study results will be published in open access scientific journals and disseminated nationally in Ethiopia.

TRIAL REGISTRATION NUMBER

NCT06223854.

Determinants of micronutrient supplementation during pregnancy among women in three sub-Saharan African countries: a multilevel logistic regression model

Background

Poor maternal nutrition during pregnancy is a common cause of poor maternal and infant outcomes. Micronutrient deficiencies are common among pregnant women in low- and middle-income countries, including sub-Saharan Africa. Pregnant women are recommended to take micronutrients like iron or folic acid and deworming medication during pregnancy. Therefore, this study was conducted to assess micronutrient intake and its associated factors among pregnant women in three countries using the most recent demographic and health survey.

Methods

We used data from the most recent demographic and health surveys, which were carried out between 2019 and 2022 in three sub-Saharan African countries. The study included a weighted sample of 13,568 reproductive-age women who had given birth within the five years prior to the survey. Utilizing multilevel logistic regression, the factors associated with the dependent variable were identified. Model comparison and fitness were assessed using the deviance (-2LLR), likelihood ratio test, median odds ratio, and intra-class correlation coefficient. Ultimately, factors were deemed statistically significant if they had a p-value less than 0.05.

Results

The pooled prevalence of micronutrient intake among pregnant women during pregnancy of last birth was 77.56% (95% CI: 76.85%-78.25%). Factors like age [AOR = 1.78; 95% CI (1.14, 2.77)], educational status [AOR = 1.49; 95% CI (1.23, 1.79)], marital status [AOR = 0.66; 95% CI (0.58, 0.75)], working status [AOR = 1.17; 95% CI (1.01, 1.34)], media exposure [AOR = 1.20; 95% CI (1.05, 1.38)], preceding birth interval [AOR = 1.17; 95% CI (1.01, 1.34)], number of ANC visits [AOR = 1.65; 95% CI (1.29, 2.10)], and residence [AOR = 1.19; 95% CI (1.03, 1.37)] were significantly associated with micronutrient intake among pregnant women.

Conclusions

More than three-fourths of the study subjects were micronutrient supplemented during their pregnancy. Improving women's education, disseminating nutrition information through media, providing more attention to young pregnant women who live in rural areas, increasing the number of ANC visits, and women's empowerment are strongly recommended.

Improvement of serum folate status in the US women of reproductive age with fortified iodised salt with folic acid (FISFA study)

OBJECTIVE

Mandatory folic acid fortification of enriched grains has reduced neural tube defect prevalence in several countries. We examined salt as an additional vehicle for folic acid fortification. The primary objective was to examine the change in serum folate concentration after 1 month of consumption of fortified iodised salt with folic acid (FISFA) among women of reproductive age. The secondary objectives were to examine (1) the feasibility of implementing FISFA intervention and (2) the acceptability of FISFA.

DESIGN

We conducted a pre–post intervention study (January–April 2023). Participants received a FISFA saltshaker with the study salt (1 g of sodium chloride salt fortified with 100 mcg of folic acid) to use instead of regular table salt for 1 month. Serum folate was measured using the Elecsys Folate-III immunoassay method at baseline and 1-month endpoint. Change in serum folate was assessed using a two-tailed Wilcoxon signed rank test for paired samples.

SETTING

Metropolitan city, Southern USA.

PARTICIPANTS

Non-pregnant, 18–40-year-old women who lived alone/with a partner.

RESULTS

Thirty-two eligible women consented to participate, including eleven non-Hispanic-White, eleven non-Hispanic-Black and ten Hispanic. Post-intervention, there was a significant increase in median serum folate concentration of 1·40 nmol/l (IQR 0·74–2·05; P < 0·001) from 24·08 nmol/l to 25·96 nmol/l in an analytical sample of n 29. An increase was seen in 28/29 (93 %) participants. Feasibility: 100 % study consent and compliance. FISFA acceptability: 25 d average use; 1·28 g average daily intake; 96·7 % and 90 % reported taste and colour of FISFA as highly acceptable, respectively.

CONCLUSIONS

FISFA is an effective approach to increasing serum folate concentrations among women of reproductive age. Findings should be replicated in a larger study.

Certification and long-term stability monitoring of low-content folic acid and 5-methyltetrahydrofolate in human plasma certified reference material by isotope dilution ultra-high performance liquid chromatography/tandem mass spectrometry

A reliable measurement of blood folate levels is necessary in the clinical field to prevent serious diseases such as cognitive impairment and neural tube defects. Herein, the certification of the low-content folic acid (FA) and 5-methyltetrahydrofolate (5-Me-THF) in human plasma certified reference material (KRISS CRM 111-01-018) was performed. A human plasma pool obtained from the Korean Red Cross was used as a CRM candidate. The certification of the human plasma CRM was performed by isotope dilution ultra-performance liquid chromatography/tandem mass spectrometry. Two-dimensional liquid chromatography was employed to confirm the validity of the analytical method for FA due to the susceptibility of FA to matrix effects because of its limited quantity. The CRM stability was evaluated at -20 °C for 2 months and at -70 °C for up to 12 months to determine the certified value of the CRM. The certified value of the CRM was (84.6 ± 4.3) ng kg-1 and (5.80 ± 0.47) μg kg-1 for FA and 5-Me-THF, respectively. The homogeneity of the CRM was 1.64% and 3.10% for FA and 5-Me-THF, respectively. Further long-term stability assessments were conducted, indicating that the CRM remains valid for at least 58 months at -70 °C for FA and 48 months for 5-Me-THF. Compared to other blood-based CRMs, this CRM has lower folate levels, making it helpful in establishing analytical methods for a broader range of folate levels.

Maternal serum unmetabolized folic acid concentration following multivitamin and mineral supplementation with or without folic acid after 12 weeks gestation: A randomized controlled trial

Pregnant women are advised to take folic acid (FA) supplements before conception and during the first trimester of pregnancy. Many women continue FA supplementation throughout pregnancy, and concerns have been raised about associations between excessive FA intake and adverse maternal and child health outcomes. Unmetabolized folic acid (UMFA) is found in serum after high FA intakes and is proposed as a biomarker for excessive FA intake. We aimed to determine if removing FA from prenatal micronutrient supplements after 12 weeks of pregnancy reduces serum UMFA concentrations at 36 weeks gestation. In this double-blind, randomized controlled trial conducted in South Australia, 103 women with a singleton pregnancy were randomly assigned at 12-16 weeks gestation to take a micronutrient supplement containing no FA or 800 µg/day FA from enrollment until 36 weeks gestation. Ninety women (0 µg/day FA n = 46; 800 µg/day FA n = 44) completed the study. Mean, UMFA concentration was lower in the women randomized to the 0 µg/day group compared to the 800 µg/day FA group, 0.6 ± 0.7 and 1.4 ± 2.7 nmol/L, respectively. The adjusted mean difference (95% CI) in UMFA between the groups was [-0.85 (-1.62, -0.08) nmol/L, p = 0.03]. Maternal serum and red blood cell folate concentrations were lower in the 0 µg/day FA group than in the 800 µg/day group (median 23.2 vs. 49.3 and 1335 vs. 1914 nmol/L, respectively; p < 0.001). Removing FA at 12-16 weeks gestation from prenatal micronutrient supplements reduced the concentration of UMFA at 36 weeks gestation.

The causal relationship between hydatidiform mole and nutrients: A two-sample Mendelian randomization study

BACKGROUND

Hydatidiform mole (HM), a subset of gestational trophoblastic disease, is considered precancerous and exhibits geographical variation. The incidence of HM is linked to nutritional factors. This study aimed to investigate the causal relationship between nutrients and HM using a bidirectional two-sample Mendelian randomization (MR) approach.

METHODS

We utilized publicly available genome-wide association study data to assess the causal associations between levels of specific vitamins (retinol, vitamins B12, B6, C, D, E, folate, and carotene) and minerals (iron, calcium, and magnesium) with HM. The MR analysis was conducted and reported following the STROBE-MR guidelines, employing MR Egger and inverse variance weighted (IVW) methods to estimate associations, with MR-PRESSO for pleiotropy testing.

RESULTS

The study revealed vitamin B6 as a significant protective factor against HM (MR-Egger OR: 0.094, 95 % CI: 0.011-0.0778, P < 0.05; IVW OR: 0.365, 95 % CI: 0.142-0.936, P < 0.05). Folate and magnesium showed suggestive associations with HM, whereas most other nutrients did not exhibit a causal relationship. MR-PRESSO analysis supported the absence of horizontal pleiotropy of vitamin B6. Besides, reverse MR analysis did not reveal a significant causal association between HM and serum nutrient levels, suggesting that differences of nutrients in HM patients may not be directly attributed to the mole.

CONCLUSION

This MR study provides evidence that vitamin B6 may protect against HM, and suggests potential roles for folate and magnesium in HM development, while highlighting the need for further research to confirm these findings.

Supplementation with Folic Acid or 5-Methyltetrahydrofolate and Prevention of Neural Tube Defects: An Evidence-Based Narrative Review

Background: Folic acid (FA), which in its chemical form is pteroylglutamic acid, is the fully oxidised, water-soluble, monoglutamic form of vitamin B9. This compound is part of the folate group but with higher bioavailability, and it is found in vitamin supplements and fortified foods and drugs. Folate metabolism is complex and associated with various metabolic pathways, all of which confer protection on the cell and allow its survival. Methods: We conducted a non-systematic search of articles published in English and Spanish including controlled trials, cohort studies, systematic re-views, and meta-analyses were included, as well as key studies in animal models related to pharmacokinetic studies. Search terms encompassed: "folic acid", "folates", "5-metyltetrahydrofolate", "5-MTHF", "neural tube defects", "supplementation", "fortification", AND "homocysteine" Results: A crucial role demonstrated for FA is to help prevent neural tube defects (NTDs). However, more studies are definitely still needed to establish 5-MTHF as a safe and effective therapeutic approach comparable with FA. Moreover, there is a lack of clinical studies that evaluate the efficacy of 5-MTHF supplementation in the prevention of NTDs. The present evidence-based narrative review discusses differences between FA and 5-MTHF in terms of structure, metabolism, bioavailability, clinical efficacy, and safety. Conclusions: Despite the potential value of 5-MTHF as an alternative to FA, clinical studies would be urgently needed to support the efficacy, dosage, timing, and/or safety of its use as a supplement.

Maternal Folic Acid and Dietary Folate Intake in Relation to Sex Ratio at Birth and Sex-Specific Birth Weight in China

BACKGROUND

It is well-established that prenatal folic acid supplements can reduce neural tube defects. However, the associations between folic acid supplementation, dietary folate intake, and overall folate intake with sex-specific birth outcomes are not yet fully understood.

OBJECTIVES

This study aims to investigate the association of periconceptional folic acid supplement, dietary folate, and total folate intake with the sex ratio at birth and sex-specific birth weight.

METHODS

Data were sourced from a cross-sectional survey conducted between August and December 2013 in Northwest China, involving 7318 infants and their mothers, recruited using a stratified multistage random sampling method. Folic acid supplements (400 μg/d) were ascertained via a retrospective in-person interview. Dietary folate was evaluated using a validated food frequency questionnaire. Birth outcomes, including sex and weight at birth, were obtained from the Medical Certificate of Birth. Generalized linear models were employed to calculate relative risks (RRs) or differences with 95% confidence intervals (CIs).

RESULTS

No association or dose-response relationship was observed between folic acid supplement, dietary folate, and total folate intake during periconception and the likelihood of male births. However, women who took folic acid supplements during pre- and post-conception were associated with an increased male birth weight by 52.8 (8.1 to 97.5) g. Additionally, the total folate intake during periconception was associated with birth weight for males (upper vs. lower tertile: β = 38.8, 95%CI: 5.0 to 72.5 g, p-trend = 0.024) and females (upper vs. lower tertile: β = 42.4, 95%CI: 6.7 to 78.1; p-trend = 0.022).

CONCLUSIONS

Our findings indicate that periconceptional total folate intake does not correlate with sex ratio at birth but was positively linked to infant birth weights, regardless of gender. These findings offer novel insights into potential benefits of total folate intake, beyond the prevention of neural tube defects, for policymakers and public health.

Bias analyses to investigate the impact of differential participation: Application to a birth defects case-control study

BACKGROUND

Certain associations observed in the National Birth Defects Prevention Study (NBDPS) contrasted with other research or were from areas with mixed findings, including no decrease in odds of spina bifida with periconceptional folic acid supplementation, moderately increased cleft palate odds with ondansetron use and reduced hypospadias odds with maternal smoking.

OBJECTIVES

To investigate the plausibility and extent of differential participation to produce effect estimates observed in NBDPS.

METHODS

We searched the literature for factors related to these exposures and participation and conducted deterministic quantitative bias analyses. We estimated case-control participation and expected exposure prevalence based on internal and external reports, respectively. For the folic acid-spina bifida and ondansetron-cleft palate analyses, we hypothesized the true odds ratio (OR) based on prior studies and quantified the degree of exposure over- (or under-) representation to produce the crude OR (cOR) in NBDPS. For the smoking-hypospadias analysis, we estimated the extent of selection bias needed to nullify the association as well as the maximum potential harmful OR.

RESULTS

Under our assumptions (participation, exposure prevalence, true OR), there was overrepresentation of folic acid use and underrepresentation of ondansetron use and smoking among participants. Folic acid-exposed spina bifida cases would need to have been ≥1.2× more likely to participate than exposed controls to yield the observed null cOR. Ondansetron-exposed cleft palate cases would need to have been 1.6× more likely to participate than exposed controls if the true OR is null. Smoking-exposed hypospadias cases would need to have been ≥1.2 times less likely to participate than exposed controls for the association to falsely appear protective (upper bound of selection bias adjusted smoking-hypospadias OR = 2.02).

CONCLUSIONS

Differential participation could partly explain certain associations observed in NBDPS, but questions remain about why. Potential impacts of other systematic errors (e.g. exposure misclassification) could be informed by additional research.

Folate and Vitamin B12 Status in Women of Reproductive Age in Rural Haryana, India: Estimating Population-Based Prevalence for Neural Tube Defects

BACKGROUND

Folate and vitamin B12 deficiencies in pregnant women are associated with increased risk for adverse maternal and infant health outcomes, including neural tube defects (NTDs).

METHODS

A population-based cross-sectional survey was conducted in two rural areas in Ambala District, Haryana, India in 2017 to assess baseline folate and vitamin B12 status among women of reproductive age (WRA) and predict the prevalence of NTDs. We calculated the prevalence of folate and vitamin B12 deficiency and insufficiency by demographic characteristics among 775 non-pregnant, non-lactating WRA (18-49 years). Using red blood cell (RBC) folate distributions and an established Bayesian model, we predicted NTD prevalence. All analyses were conducted using SAS-callable SUDAAN Version 11.0.4 to account for complex survey design.

RESULTS

Among WRA, 10.1% (95% CI: 7.9, 12.7) and 9.3% (95% CI: 7.4, 11.6) had serum (<7 nmol/L) and RBC folate (<305 nmol/L) deficiency, respectively. The prevalence of RBC folate insufficiency (<748 nmol/L) was 78.3% (95% CI: 75.0, 81.3) and the predicted NTD prevalence was 21.0 (95% uncertainly interval: 16.9, 25.9) per 10,000 live births. Prevalences of vitamin B12 deficiency (<200 pg/mL) and marginal deficiency (≥200 pg/mL and ≤300 pg/mL) were 57.7% (95% CI: 53.9, 61.4) and 23.5% (95% CI: 20.4, 26.9), respectively.

CONCLUSIONS

The magnitude of folate insufficiency and vitamin B12 deficiency in this Northern Indian population is a substantial public health concern. The findings from the survey help establish the baseline against which results from future post-fortification surveys can be compared.

The effect of folic acid intake on congenital anomalies. A systematic review and meta-analysis

Background

Congenital anomalies pose a significant challenge to global health and result in considerable morbidity and mortality in early childhood. With the decline of other causes of death among children under five, the burden of congenital anomalies is rising, emphasizing the need for improved prenatal care, screening, and nutrition for pregnant women. This systematic review and meta-analysis aim to estimate the pooled effect of folic acid intake on congenital anomalies.

Methods

To identify relevant research published up until December 30/2023, we conducted electronic searches of PubMed/Medline, PubMed Central, Hinary, Google, African Journals Online, Web of Science, Science Direct, and Google Scholar databases using predefined eligibility criteria. We used Excel to extract data and evaluated the studies using the JBI appraisal checklist. We computed the pooled effect size with 95% confidence intervals for maternal folic acid intake on congenital anomalies using STATA version 17 and the DerSimonian and Laird random effects meta-analysis model. We assessed statistical heterogeneity using Cochran's Q-test, I 2 statistic, and visual examination of the funnel plot.

Results

The review included 16 case-control, cohort, and cross-sectional studies. According to the results of this systematic review and meta-analysis, maternal folic acid intake significantly lowers the incidence of congenital anomalies (odds ratio (OR), 0.23; confidence interval (CI), 0.16, 0.32). Among the included studies, both the Cochrane Q-test statistic (χ2 = 118.82, p < 0.001) and I 2 test statistic (I 2 = 87.38%, p < 0.001) revealed statistically significant heterogeneity. Egger's weighted regression (p < 0.001) and funnel plot show evidence of publication bias in this meta-analysis.

Conclusion

The results of the recent meta-analysis and systematic review have demonstrated a significant association between maternal folic acid intake and the risk of congenital anomalies. Specifically, children whose mothers received periconceptional folic acid supplementation had a 77% reduced risk of congenital anomalies. To further investigate the correlation between maternal folic acid supplementation and the occurrence of various congenital anomalies, particularly in developing countries, it is recommended that a comprehensive prospective study be conducted.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero/, PROSPERO (CRD42024511508).

A Comparative Study Evaluating the Effectiveness of Folate-Based B Vitamin Intervention on Cognitive Function of Older Adults under Mandatory Folic Acid Fortification Policy: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

The policies regarding the mandatory fortification of food with folic acid (FA) may impact the effectiveness of folate-based B vitamin treatment on cognitive function in older adults. We critically and systematically review the literature to assess whether food fortification policies affect folate-based B vitamin treatment efficacy on cognition function in older adults. Electronic databases, including PubMed, Web of Science, and CNKI, were searched for "Cognitive Function", "Folate", and "Older Adults". The study had specific criteria for inclusion, which were as follows: (1) the studies should initially have randomized controlled trials that were conducted on older adults aged 60 or above; (2) the studies must assess the relationship between folate status and cognitive performance; and (3) the studies should clarify the policies regarding food fortification with FA. This review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) reporting guidelines. Two reviewers independently extracted all the data, and any discrepancies were resolved by consensus. All the data collected were compiled, compared, and analyzed critically. Random effects models were used to assess the effects of interventions. The systematic review included fifty-one articles involving 42,768 participants. Of these, the 23 articles were included in the meta-analysis. The meta-analysis on the effects of folate-based B vitamin supplementation on cognitive function showed a significant overall impact (Z = 3.84; p = 0.0001; SMD, 0.18; 95% CI, 0.09, 0.28). Further analysis revealed that FA food fortification policies were not implemented in countries where folate-based B vitamin supplementation improved cognitive impairment in older adults (Z = 3.75; p = 0.0002; SMD, 0.27; 95% CI, 0.13, 0.40). However, the FA intervention did not have significant outcomes in areas where FA food fortification policies were mandatory (Z = 0.75; p = 0.45; SMD, 0.03; 95% CI, -0.06, 0.13). Supplementing with oral folic acid, alone or in combination, has been linked to improved cognitive performance in older adults. While mandatory FA fortification has the improved folic acid status, additional folate-based B vitamin supplements do not appear to influence cognitive function.

Consensus Statements for Assessment and Management of Threatened Miscarriage in the First Trimester in Pakistan: A Three-Step Modified Delphi Approach

BACKGROUND AND OBJECTIVE

It aimed to develop an expert consensus regarding the risk assessment, diagnosis, and threatened miscarriage management during the first trimester in Pakistan.

METHODS

A three-step modified Delphi method was applied to develop the consensus. Eleven specialized obstetricians and gynecologists participated in its development. If 75% or higher agreement level was attained on each assertion, it was declared as a consensus.

RESULTS

Age of 35 or above, previous history of two or more previous miscarriages, and direct strong trauma were considered to be threatened miscarriage risk factors. Infection was discussed and specified to include specific infectious diseases, like malaria, and COVID-19 as a risk factor. The experts agreed from the first time on considering endocrinological disorders, thrombophilia, and lifestyle variables as threatened miscarriage risk factors. They proposed adding a statement concerning acquired thrombophilia which was accepted unanimously. Finally, experts agreed on the importance of educating pregnant women about factors whose risk can be modified by modifying their behavior. As for diagnosis statements, it was agreed to be trifold: physical examination, imaging, and laboratory testing. Physical examination included abdominal and pelvic exams but focused more on vaginal examination with speculum to identify bleeding severity and etiology. The statements regarding the imaging approaches to diagnose threatened miscarriage in the first trimester achieved a consensus in most statements. TVS was recommended to check on uterine structural abnormalities, fetus viability focusing on heartbeat and crown-to-rump length, gestation sac size and emptiness, subchorionic hematoma, and ectopic pregnancy. Each was defined on how to identify and diagnose in separate statements. Statements about laboratory tests indicated the need for human chorionic gonadotropin hormone assessment whether serial or once is dependent on the ultrasound. Recommended hematologic investigations include complete blood count for anemia, Rh factor for potential bleeding risk and in special cases, thrombophilia assessment is undertaken. The first and foremost management aspect was follow-up while most management statements were controversial, and some were altogether removed with only some reaching agreement after discussion.

CONCLUSION

These consensus statements aggregated the best available evidence and experts' opinion-supported statements to improve patient education, risk assessment, diagnosis, and evaluation as well as management of threatened miscarriage during the first trimester in Pakistan.

The Association of Infant Birth Sizes and Anemia under Five Years Old: A Population-Based Prospective Cohort Study in China

Infant birth sizes are vital clinical parameters to predict poor growth and micronutrient deficiency in early life. However, their effects on childhood anemia remain unclear. We aimed to explore the associations between birth weight, crown-heel length, and head circumference with anemia in early childhood, as well as potential modification factors. This population-based prospective cohort study included 204,556 participants with singleton live births delivered at gestational ages of 28-42 weeks. A logistic regression model was used to estimate the associations of the measures of infant birth size and their Z-score with anemia under five years old. There were 26,802 (13.10%) children under five years old who were diagnosed has having anemia. Compared with children who did not have anemia, children who had anemia had a lower birth weight and smaller head circumference and a longer crown-heel length (all p-values < 0.05). After adjusting for confounders, not only birth weight (β coefficient, -0.008; 95% CI, -0.011--0.004; p < 0.001) and head circumference (β coefficient, -0.004; 95% CI, -0.007--0.001; p = 0.009), but also the related Z-scores were negatively associated with childhood anemia, while the trends for crown-heel length were the opposite. We further found significant interactions of folic acid use and maternal occupation with infant birth sizes. In conclusion, infants having abnormal sizes at birth are significantly associated with the risk for childhood anemia, which can be modified by folic acid use during pregnancy and maternal occupation.

Paediatric hydrocephalus

Hydrocephalus is classically considered as a failure of cerebrospinal fluid (CSF) homeostasis that results in the active expansion of the cerebral ventricles. Infants with hydrocephalus can present with progressive increases in head circumference whereas older children often present with signs and symptoms of elevated intracranial pressure. Congenital hydrocephalus is present at or near birth and some cases have been linked to gene mutations that disrupt brain morphogenesis and alter the biomechanics of the CSF-brain interface. Acquired hydrocephalus can develop at any time after birth, is often caused by central nervous system infection or haemorrhage and has been associated with blockage of CSF pathways and inflammation-dependent dysregulation of CSF secretion and clearance. Treatments for hydrocephalus mainly include surgical CSF shunting or endoscopic third ventriculostomy with or without choroid plexus cauterization. In utero treatment of fetal hydrocephalus is possible via surgical closure of associated neural tube defects. Long-term outcomes for children with hydrocephalus vary widely and depend on intrinsic (genetic) and extrinsic factors. Advances in genomics, brain imaging and other technologies are beginning to refine the definition of hydrocephalus, increase precision of prognostication and identify nonsurgical treatment strategies.

Association of MTHFR (C677T, A1298C) and MTRR A66G polymorphisms with fatty acids profile and risk of neural tube defects

OBJECTIVE

This study aims to determine if 5,10-methylenetetrahydrofolate reductase (MTHFR C677T and A1298C) and methionine synthase reductase (MTRR A66G) gene polymorphisms were associated with fatty acid (FA) levels in mothers of fetuses with neural tube defects (NTDs) and whether these associations were modified by environmental factors.

METHODS

Plasma FA composition was assessed using capillary gas chromatography. Concentrations of studied FA were compared between 42 mothers of NTDs fetuses and 30 controls as a function of each polymorphism by the Kruskal-Wallis nonparametric test.

RESULTS

In MTHFR gene C677T polymorphism, cases with (CT + TT) genotype had lower monounsaturated FAs (MUFA) and omega-3 polyunsaturated FA (n-3 PUFA) levels, but higher omega-6 polyunsaturated FAs (n-6 PUFA) and omega-6 polyunsaturated FAs: omega-3 polyunsaturated FAs (n-6:n-3) ratio levels. In MTRR gene A66G polymorphism, cases with (AG + GG) genotype had lower MUFA levels, but higher PUFA and n-6 PUFA levels. Controls with (AG + GG) genotype had lower n-6 PUFA levels. In MTHFR gene C677T polymorphism, cases with smoking spouses and (CT + TT) genotype had lower MUFA and n-3 PUFA levels, but higher PUFA, n-6 PUFA, and n-6:n-3 ratio levels. Cases with (CT + TT) genotype and who used sauna during pregnancy had lower n-3 PUFA levels. In MTRR gene A66G polymorphism, cases with (AG + GG) genotype and who used sauna during pregnancy had higher PUFA and n-6 PUFA levels.

CONCLUSIONS

Further research is required to clarify the association of FA metabolism and (MTHFR, MTRR) polymorphisms with NTDs.

Multivitamin Use Among Hispanic Women of Reproductive Age in the United States, 2013-2022

Background: The U.S. Public Health Service and the Institute of Medicine recommend that all women capable of becoming pregnant consume 400 μg of folic acid daily to help prevent neural tube defects (NTDs). Hispanic women are at higher risk of having babies with NTDs than non-Hispanic White women. This study assessed multivitamin (MV) use, a main source of folic acid, among Hispanic women of reproductive age using a survey of solely U.S. Hispanic adults. Materials and Methods: MV use was assessed as part of Porter Novelli's Estilos survey, fielded annually through the largest online U.S. Hispanic panel, Offerwise's QueOpinas. During the study period of 2013-2022, 9,999 surveys were completed; selection was weighted to match the U.S. Census American Community Survey proportions. Log-binomial regression models were applied to estimate MV use trends by age groups, acculturation levels, and pregnancy intention. Results: Among 3,700 Hispanic women of reproductive age, overall no MV use increased from 39.3% in 2013 to 54.7% in 2022 (p for trend <0.0001), especially among Hispanic women aged 18-34 years and those classified as acculturated. Among women planning to get pregnant, daily MV use was 31.1% in 2013 compared with 18.7% in 2020-2022 (p = 0.04). Conclusions: Given the increase in no MV use among Hispanic women of reproductive age, targeted interventions may help reach at-risk groups for NTDs prevention.

A global update on the status of prevention of folic acid-preventable spina bifida and anencephaly in year 2022

BACKGROUND

Mandatory fortification of staple foods with folic acid is an effective public health strategy to prevent folic acid-preventable spina bifida and anencephaly (FAP SBA). We estimated the global proportion of FAP SBA prevented through mandatory folic acid fortification of cereal grains (i.e., wheat flour, maize flour, and rice).

METHODS

We used year 2022 data from the Food Fortification Initiative to identify countries (n = 69) with mandatory fortification of grains that includes folic acid. Sixty-eight countries were eligible for analysis with complete data. Proportion of FAP SBA prevention was modeled assuming >150 mcg/day of folic acid fortification protects against FAP SBA, reducing post-fortification prevalence to a lowest achievable level of 0.5 cases per 1000 births.

RESULTS

Our analysis found that a total of 63,520 cases of FAP SBA were prevented in the year 2022 in 68 countries implementing mandatory folic acid fortification of grains with folic acid. This translated to a 23.7% prevention of all possible FAP SBA prevention globally. An excess of 204,430 cases of FAPSBA still occurred in over 100 countries where mandatory staple food fortification with folic acid is not implemented.

CONCLUSION

Our study showed that only a quarter of all FAP SBA cases were averted through mandatory folic acid fortification in the year 2022; many countries are not implementing the policy, resulting in a large proportion of FAP SBA cases that can be prevented. Fortification will help countries with achieving 2030 Sustainable Development Goals on neonatal- and under-five mortality, disability, stillbirths, and elective terminations prevention, from FAP SBA.

Expanding Fortification with Folic Acid: Thinking Outside the Cereal-Grain Box

(1) Background: Fortifying maize and wheat flours with folic acid has effectively reduced neural tube defect-affected births. However, maize and wheat flours may not be widely consumed in all countries; further reduction in neural tube defect-affected births could benefit from the identification of alternative food vehicles. We aimed to use dietary intake or apparent consumption data to determine alternative food vehicles for large-scale fortification with folic acid in low-income and lower-middle-income countries (LILMICs) and identify current research related to examining the technological feasibility of fortifying alternative foods with folic acid. (2) Methods: We identified 81 LILMICs, defined by the World Bank's (WB) 2018 income classifications. To identify dietary intake or apparent consumption, we reviewed WB's Microdata Library and Global Health Data Exchange for national surveys from 1997-2018. We reviewed survey reports for dietary intake or apparent consumption data and analyzed survey datasets for population coverage of foods. We defined alternative food vehicles as those that may cover/be consumed by ≥30% of the population or households; cereal grains (maize and wheat flours and rice) were included as an alternative food vehicle if a country did not have existing mandatory fortification legislation. To identify current research on fortification with folic acid in foods other than cereal grains, we conducted a systematic review of published literature and unpublished theses, and screened for foods or food products. (3) Results: We extracted or analyzed data from 18 national surveys and countries. The alternative foods most represented in the surveys were oil (n = 16), sugar (n = 16), and salt (n = 14). The coverage of oil ranged from 33.2 to 95.7%, sugar from 32.2 to 98.4%, and salt from 49.8 to 99.9%. We found 34 eligible studies describing research on alternative foods. The most studied alternative foods for fortification with folic acid were dairy products (n = 10), salt (n = 6), and various fruit juices (n = 5). (4) Conclusions: Because of their high coverage, oil, sugar, and salt emerge as potential alternative foods for large-scale fortification with folic acid. However, except for salt, there are limited or no studies examining the technological feasibility of fortifying these foods with folic acid.

Risk of Excess Maternal Folic Acid Supplementation in Offspring

Folate, also known as vitamin B9, facilitates the transfer of methyl groups among molecules, which is crucial for amino acid metabolism and nucleotide synthesis. Adequate maternal folate supplementation has been widely acknowledged for its pivotal role in promoting cell proliferation and preventing neural tube defects. However, in the post-fortification era, there has been a rising concern regarding an excess maternal intake of folic acid (FA), the synthetic form of folate. In this review, we focused on recent advancements in understanding the influence of excess maternal FA intake on offspring. For human studies, we summarized findings from clinical trials investigating the effects of periconceptional FA intake on neurodevelopment and molecular-level changes in offspring. For studies using mouse models, we compiled the impact of high maternal FA supplementation on gene expression and behavioral changes in offspring. In summary, excessive maternal folate intake could potentially have adverse effects on offspring. Overall, we highlighted concerns regarding elevated maternal folate status in the population, providing a comprehensive perspective on the potential adverse effects of excessive maternal FA supplementation on offspring.

Folate and vitamin B12 status and predicted neural tube defects risk among nonpregnant women of reproductive age from the Malawi National Micronutrient Survey, 2015-2016

BACKGROUND

Maternal folate and vitamin B12 deficiency can lead to serious adverse pregnancy outcomes. There are no nationally representative estimates on folate and vitamin B12 status among women of reproductive age (WRA) in Malawi.

OBJECTIVE

We assessed folate and vitamin B12 status among nonpregnant WRA in Malawi and predicted the risk of folate-sensitive neural tube defects (NTDs) were they to become pregnant.

METHODS

Using data from the cross-sectional, nationally representative 2015-2016 Malawi Micronutrient Survey, we calculated the proportion of folate and vitamin B12 deficiency and insufficiency by demographic characteristics among 778 nonpregnant WRA (15-49 years). We predicted NTD prevalence using red blood cell (RBC) folate distributions and a published Bayesian model of the association between RBC folate and NTD risk. Analyses accounted for complex survey design.

RESULTS

Among WRA, 8.5% (95% CI: 6.2, 11.6) and 13.3% (10.0, 17.4) had serum (<7 nmol/L) and RBC folate (<305 nmol/L) deficiency, respectively. The proportion of vitamin B12 deficiency (<148 pmol/L) and insufficiency (≤221 pmol/L) was 11.8% (8.6, 16.0) and 40.6% (34.1, 47.4), respectively. RBC folate insufficiency (<748 nmol/L, defined as the concentration associated with the threshold for elevated NTD risk: >8 cases per 10,000 births) was widespread: 81.4% (75.0, 86.4). The predicted NTD risk nationally was 24.7 cases per 10,000 live births. RBC folate insufficiency and higher predicted NTD risk were more common among WRA living in urban areas or with higher education.

CONCLUSIONS

These findings highlight the importance of nutritional and NTD surveillance in Malawi and the opportunity for improving folate and vitamin B12 nutrition among Malawian WRA.

Micronutrient supplement recommendations in pregnancy vary across a geographically diverse range of countries: a narrative review

Specific food supplements are essential during preconception and pregnancy to ensure adequate intake of vitamins and minerals to support fetal growth and development and metabolic changes in the maternal body. Our objective was to identify food supplement recommendations, particularly those of folic acid, iron, Vitamin D, and iodine, during preconception and/or pregnancy across a geographically diverse range of countries. Further, we investigated whether country location and income-level related to the recommendations. We performed an electronic search and identified country-specific preconception and pregnancy food supplement recommendations, policy documents, and official guidelines of national organizations informing recommendations. To ensure the data were as accurate as possible, country-specific experts were contacted. Data were collected in 2017 and reevaluated in 2022. Country income level was determined by the World Bank classification. Each inspected country (n = 43) recommended folic acid supplementation, typically 400 µg/day, before and during pregnancy. About half of the countries recommended an iron supplement (dose range, 16-195 mg/day) and one quarter Vitamin D (typically 10 µg/d in higher latitudes) and iodine (150-200 µg/day). Country location and income level had some influence on the recommendations. Vitamin D was more often recommended in higher latitude, high-income countries. Almost all upper-middle and lower-middle income countries recommended iron supplementation, whereas less than one third of high-income countries had a corresponding recommendation. Findings suggest that food supplement recommendations for pregnant women vary across countries, likely influenced by geographic location as well as income level. These data may be used in the harmonization of food supplement recommendations.

Associations between maternal periconceptional alcohol consumption and risk of omphalocele among offspring, National Birth Defects Prevention Study, 1997-2011

OBJECTIVE

Previous studies of alcohol consumption during pregnancy and omphalocele have produced mixed results. We updated an earlier analysis of National Birth Defects Prevention Study (NBDPS) data, adding six years of participants, to examine associations between maternal alcohol consumption and omphalocele.

METHODS

NBDPS was a multi-site, population-based case-control study in the United States. Cases were identified from birth defect surveillance programs in 10 states; controls were liveborn infants without a birth defect randomly selected from the same catchment areas. Mothers self-reported alcohol consumption during the periconceptional period (one month before through the third gestational month) via telephone interview. Our study included mothers of 410 omphalocele cases and 11,219 controls with estimated dates of delivery (EDDs) during 1997-2011. We used logistic regression to estimate adjusted odds ratios (AORs) and 95% confidence intervals (CIs) for periconceptional alcohol consumption and omphalocele. We performed a probabilistic bias analysis to evaluate the impact of alcohol exposure misclassification on our results.

RESULTS

Overall, 44% of case and 38% of control mothers reported periconceptional alcohol consumption; 22% and 17%, respectively, reported binge drinking. Any maternal periconceptional alcohol consumption was associated with modestly increased odds of omphalocele (AOR 1.35, 95% CI 1.09, 1.68), as was binge drinking (AOR 1.47, 95% CI 1.08, 2.01). Our bias analysis yielded estimates further from the null.

CONCLUSIONS

We observed modest associations between maternal periconceptional alcohol consumption and omphalocele. Based on our bias analysis, studies of alcohol and birth defects not accounting for exposure misclassification may underestimate associations.

Epigenetic Genome Modifications during Pregnancy: The Impact of Essential Nutritional Supplements on DNA Methylation

Pregnancy is an extremely stressful period in a pregnant woman's life. Currently, women's awareness of the proper course of pregnancy and its possible complications is constantly growing. Therefore, a significant percentage of women increasingly reach for various dietary supplements during gestation. Some of the most popular substances included in multi-ingredient supplements are folic acid and choline. Those substances are associated with positive effects on fetal intrauterine development and fewer possible pregnancy-associated complications. Recently, more and more attention has been paid to the impacts of specific environmental factors, such as diet, stress, physical activity, etc., on epigenetic modifications, understood as changes occurring in gene expression without the direct alteration of DNA sequences. Substances such as folic acid and choline may participate in epigenetic modifications by acting via a one-carbon cycle, leading to the methyl-group donor formation. Those nutrients may indirectly impact genome phenotype by influencing the process of DNA methylation. This review article presents the current state of knowledge on the use of folic acid and choline supplementation during pregnancy, taking into account their impacts on the maternal-fetal unit and possible pregnancy outcomes, and determining possible mechanisms of action, with particular emphasis on their possible impacts on epigenetic modifications.

Folic acid supplements and perinatal mortality in China

Introduction

Periconceptional use of multivitamins containing folic acid prevents external major birth defects, especially neural tube defects. We aimed to explore the effects of maternal folic acid supplementation alone on perinatal mortality with or without external major birth defects plus neural tube defects.

Methods

From the China-US Collaborative Project for Neural Tube Defects Prevention, we identified 222, 303 singleton pregnancies with detailed information on periconceptional folic acid use, defined as folic acid supplementary before the last menstrual date until to the end of the first trimester. Perinatal mortality included stillbirths after 20 weeks' gestation and early neonatal deaths within 7 days of delivery.

Results

Among the fetuses or infants of women who did not take folic acid, the rate of perinatal mortality was 2.99% and 1.62% at least 20 weeks' gestation in the northern and southern regions. Among the fetuses or infants of the women with periconceptional use of folic acid, the rates were 1.85% and 1.39% in the northern and southern region. The estimated relative risk for perinatal mortality [adjusted risk ratio (RR), 0.72; 95% confidence interval (CI), 0.61- 0.85], stillbirth (adjusted RR, 0.78; 95% CI, 0.64-0.96), early neonatal mortality (adjusted RR, 0.61; 95% CI, 0.45-0.82), and neonatal death (adjusted RR, 0.64; 95% CI, 0.49-0.83) in northern China was significantly decreased in association with periconceptional folic acid supplementation. Compared with northern, there was a lesser effect in southern China.

Conclusion

Periconceptional intake of 400μg folic acid daily reduces the overall risk perinatal mortality, as well as the risk from external major birth defects and neural tube defects, especially in northern China.

Global heterogeneity in folic acid fortification policies and implications for prevention of neural tube defects and stroke: a systematic review

Background

Folic acid (pteroylmonoglutamic acid) supplements are highly effective for prevention of neural tube defects (NTD) prompting implementation of mandatory or voluntary folic acid fortification for prevention of NTDs. We used plasma folate levels in population studies by country and year to compare effects of folic acid fortification types (mandatory or voluntary folic acid fortification policies) on plasma folate levels, NTD prevalence and stroke mortality rates.

Methods

We conducted systematic reviews of (i) implementation of folic acid fortification in 193 countries that were member states of the World Health Organization by country and year, and (ii) estimated population mean plasma folate levels by year and type of folic acid fortification. We identified relevant English language reports published between Jan 1, 1990 and July 31, 2023 using Google Scholar, Medline, Embase and Global Health. Eligibility criteria were observational or interventional studies with >1000 participants. Studies of pregnant women or children <15 years were excluded. Using an ecological study design, we examined the associations of folic acid fortification types with NTD prevalence (n = 108 studies) and stroke mortality rates (n = 3 countries).

Findings

Among 193 countries examined up to 31 July 2023, 69 implemented mandatory folic acid fortification, 47 had voluntary fortification, but 77 had no fortification (accounting for 32%, 53% and 15% of worldwide population, respectively). Mean plasma folate levels were 36, 21 and 17 nmol/L in populations with mandatory, voluntary and no fortification, respectively (and proportions with mean folate levels >25 nmol/L were 100%, 15% and 7%, respectively). Among 75 countries with NTD prevalence, mean (95% CI) prevalence per 10,000 population were 4.19 (4.11-4.28), 7.61 (7.47-7.75) and 9.66 (9.52-9.81) with mandatory, voluntary and no folic acid fortification, respectively. However, age-standardised trends in stroke mortality rates were unaltered by the introduction of folic acid fortification.

Interpretation

There is substantial heterogeneity in folic acid fortification policies worldwide where folic acid fortification are associated with 50-100% higher population mean plasma folate levels and 25-50% lower NTD prevalence compared with no fortification. Many thousand NTD pregnancies could be prevented yearly if all countries implemented mandatory folic acid fortification. Further trials of folic acid for stroke prevention are required in countries without effective folic acid fortification policies.

Funding

Medical Research Council (UK) and British Heart Foundation.

Clinical presentation and outcomes of neonates born with neural tube defects- an experience from a level III B NICU in Western India

PURPOSE

Neural tube defects (NTDs) are one of the most common congenital anomalies and a cause of chronic disability. The study was done to study outcomes of neural tube defects admitted at a tertiary level neonatal intensive care unit (NICU) from 2018 to 2022, a period of 4 years that also coincided with the COVID pandemic. The secondary outcome was to study the clinical presentation, associated anomalies and epidemiological features.

METHODS

It was a retrospective observational study; data of infants was obtained from medical records and analysis was done.

RESULTS

Thirty-four neonates were enrolled, of which there were 16 (47%) males and 18 (53%) females. History of pre-pregnancy maternal folate intake was present in 4 (11.7%) cases. 33 (97%) babies were diagnosed with meningomyelocele (MMC) and one each had anencephaly, iniencephaly and encephalocele, of which one had frontal and two had occipital encephalocele. The median age of surgery was 16 days of life with primary repair being the most common procedure followed by MMC repair with VP shunt. Twenty babies (58.8%) were discharged successfully, while 9 (26.5%) expired and 5 (14.7%) were discharged against medical advice; which can be attributed to the financial problems of the patients in a developing country. The overall deaths in our series were four (26.5%) which is slightly higher than other studies which may be due to the fact that this study was conducted during the COVID era with lesser rates of folate supplementation, reduced access to prenatal diagnosis coupled with poor follow-up and compliance of patients post-surgical repair.

CONCLUSION

This study emphasizes the importance of periconceptional folic acid supplementation, prenatal diagnosis, early surgery and meticulous follow-up as being pivotal to improving outcomes in children with NTDs.

MTHFR and risk of stroke and heart disease in a low-folate population: a prospective study of 156 000 Chinese adults

BACKGROUND

The relevance of folic acid for stroke prevention in low-folate populations such as in China is uncertain. Genetic studies of the methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism, which increases plasma homocysteine (tHcy) levels, could clarify the causal relevance of elevated tHcy levels for stroke, ischaemic heart disease (IHD) and other diseases in populations without folic acid fortification.

METHODS

In the prospective China Kadoorie Biobank, 156 253 participants were genotyped for MTHFR and 12 240 developed a stroke during the 12-year follow-up. Logistic regression was used to estimate region-specific odds ratios (ORs) for total stroke and stroke types, IHD and other diseases comparing TT genotype for MTHFR C677T (two thymine alleles at position 677 of MTHFR C677T polymorphism) vs CC (two cytosine alleles) after adjustment for age and sex, and these were combined using inverse-variance weighting.

RESULTS

Overall, 21% of participants had TT genotypes, but this varied from 5% to 41% across the 10 study regions. Individuals with TT genotypes had 13% (adjusted OR 1.13, 95% CI 1.09-1.17) higher risks of any stroke [with a 2-fold stronger association with intracerebral haemorrhage (1.24, 1.17-1.32) than for ischaemic stroke (1.11, 1.07-1.15)] than the reference CC genotype. In contrast, MTHFR C677T was unrelated to risk of IHD or any other non-vascular diseases, including cancer, diabetes and chronic obstructive lung disease.

CONCLUSIONS

In Chinese adults, the MTHFR C677T polymorphism was associated with higher risks of stroke. The findings warrant corroboration by further trials of folic acid and implementation of mandatory folic acid fortification programmes for stroke prevention in low-folate populations.

Analysis of Gut Characteristics and Microbiota Changes with Maternal Supplementation in a Neural Tube Defect Mouse Model

Adequate nutrient supply is crucial for the proper development of the embryo. Although nutrient supply is determined by maternal diet, the gut microbiota also influences nutrient availability. While currently there is no cure for neural tube defects (NTDs), their prevention is largely amenable to maternal folic acid and inositol supplementation. The gut microbiota also contributes to the production of these nutrients, which are absorbed by the host, but its role in this context remains largely unexplored. In this study, we performed a functional and morphological analysis of the intestinal tract of loop-tail mice (Vangl2 mutants), a mouse model of folate/inositol-resistant NTDs. In addition, we investigated the changes in gut microbiota using 16S rRNA gene sequencing regarding (1) the host genotype; (2) the sample source for metagenomics analysis; (3) the pregnancy status in the gestational window of neural tube closure; (4) folic acid and (5) D-chiro-inositol supplementation. We observed that Vangl2+/Lp mice showed no apparent changes in gastrointestinal transit time or fecal output, yet exhibited increased intestinal length and cecal weight and gut dysbiosis. Moreover, our results showed that the mice supplemented with folic acid and D-chiro-inositol had significant changes in their microbiota composition, which are changes that could have implications for nutrient absorption.

Prenatal folic acid and vitamin B12 imbalance alter neuronal morphology and synaptic density in the mouse neocortex

Previous reports have provided evidence that insufficient or excessive maternal folic acid (FA) intake during pregnancy can alter neurodevelopment of the offspring by modulating prenatal neurogenesis. Furthermore, our earlier work in a mouse model confirmed long-term structural changes at the cellular level of either deficient or excessive FA supply by comparably reducing dendritic arborization of cortical projection neurons. Here, we report that excessive amounts of FA decrease arborization of deep layer projection neurons, but not upper layer neurons and that reduced complexity of deep layer neurons is not observed when folic acid is replaced by folinic acid, a stable reduced form of folate. In addition, deficiency of B12, a vitamin that critically regulates folate metabolism, causes even more marked decreases in neuronal arborization in both deep and upper layer neurons and particularly in combination with FA excess. Furthermore, both FA excess and B12 deficiency affect synaptic density and morphology. Our findings point to neurodevelopmental risks associated with insufficient amounts of prenatal B12, particularly in association with high levels of FA intake, suggesting that the neurodevelopmental program is sensitive to an imbalance in the status of these interacting micronutrients.

Association of age at menarche with gestational hypertension and preeclampsia: A large prospective cohort in China

This study explored the potential association between age at menarche and the risks of gestational hypertension and preeclampsia in Chinese women. Data were sourced from the China-US Collaborative Project for Neural Tube Defects Prevention, a large population-based cohort study. Our study consisted of 209 411 women pre-registered for pregnancy in two provinces in South China. Trained healthcare workers measured blood pressure at registration and recorded other pertinent health information. Using logistic regression, we assessed the correlations between age at menarche and the likelihood of developing gestational hypertension and preeclampsia, considering confounders such as maternal age, body mass index, ethnicity, parity, folic acid supplementation, education level, and occupation. The observed incidences for gestational hypertension and preeclampsia were 9.65% and 2.54%, respectively. The adjusted odds ratios (ORs) for gestational hypertension, based on age at menarche, were as follows: ≤13 years, 1.18 (95% confidence interval: 1.11-1.26); 14 years, 1.09 (1.04-1.15); 15 years, 1.11 (1.06-1.16); 16 years, 1.06 (1.01-1.12); and ≥17 years, 1.00 (reference; P for trend < .001). The correlation between age at menarche and preeclampsia varied across age groups, with the following respective ORs: 1.35 (1.20-1.52), 1.21 (1.09-1.34), 1.27 (1.15-1.39), 1.14 (1.03-1.26), and 1.00 (reference; P for trend < .001). This association appeared to be more pronounced in women with no folic acid supplementation and those with a lower education level. In conclusion, an earlier age at menarche seems to be linked to increased risks of gestational hypertension and preeclampsia.

Periconceptional Folic Acid Use and Its Effects on Neural Tube Defects - Five Counties, Shanxi Province, China, 2010-2016

What is already known about this topic?

Robust evidence indicates that supplementing with folic acid periconceptionally may decrease the risk of neural tube defects (NTDs) in fetuses.

What is added by this report?

Over half of the mothers in both the NTD case group and the control group utilized folic acid supplements during the periconceptional period, showing no notable variations between the two groups. However, there was a significantly higher percentage of mothers with NTD cases who exhibited poor compliance in folic acid use compared to control mothers. A significantly lowered compliance with folic acid intake was observed among women facing unintended pregnancies and those with lower education levels.

What are the implications for public health practice?

Universal education regarding folic acid action for women of childbearing age should be strengthened to improve compliance with folic acid supplementation in the periconceptional period and further reduce the prevalence of NTDs.

Periconceptional intakes of methyl donors and other micronutrients involved in one-carbon metabolism may further reduce the risk of neural tube defects in offspring: a United States population-based case-control study of women meeting the folic acid recommendations

BACKGROUND

Neural tube defects (NTDs) still occur among some women who consume 400 μg of folic acid for prevention. It has been hypothesized that intakes of methyl donors and other micronutrients involved in one-carbon metabolism may further protect against NTDs.

OBJECTIVES

To investigate whether intakes of vitamin B6, vitamin B12, choline, betaine, methionine, thiamine, riboflavin, and zinc, individually or in combination, were associated with NTD risk reduction in offspring of women meeting the folic acid recommendations.

METHODS

Data were from the National Birth Defects Prevention Study (United States population-based, case-control). We restricted deliveries between 1999 and 2011 with daily periconceptional folic acid supplementation or estimated dietary folate equivalents ≥400 μg. NTD cases were live births, stillbirths, or terminations affected by spina bifida, anencephaly, or encephalocele (n = 1227). Controls were live births without a major birth defect (n = 7095). We categorized intake of each micronutrient as higher or lower based on a combination of diet (estimated from a food frequency questionnaire) and periconceptional vitamin supplementation. We estimated NTD associations for higher compared with lower intake of each micronutrient, individually and in combination, expressed as odds ratios (ORs) and 95% confidence intervals (CIs), adjusted for age, race/ethnicity, education, and study center.

RESULTS

NTD associations with each micronutrient were weak to modest. Greater NTD reductions were observed with concurrent higher-amount intakes of multiple micronutrients. For instance, NTD odds were ∼50% lower among participants with ≥4 micronutrients with higher-amount intakes than among participants with ≤1 micronutrient with higher-amount intake (adjusted OR: 0.53; 95% CI: 0.33, 0.86). The strongest reduction occurred with concurrent higher-amount intakes of vitamin B6, vitamin B12, choline, betaine, and methionine (adjusted OR: 0.26; 95% CI: 0.09, 0.77) compared with ≤1 micronutrient with higher-amount intake.

CONCLUSIONS

Our findings support that NTD prevention, in the context of folic acid fortification, could be augmented with intakes of methyl donors and other micronutrients involved in folate metabolism.

Initiation and duration of folic acid supplementation in preventing congenital malformations

BACKGROUND

Folic acid (FA) supplementation is associated with a lower risk of the neural tube and heart defects and is recommended for women of childbearing age. Although there are detailed recommendations, differences in the initiation time and duration of FA supplementation remain poorly studied.

METHODS

A multicentre prospective study of 17,713 women was conducted. The incidence of congenital malformations in women taking a recommended dosage (e.g. 0.4 or 0.8 mg/day) of FA was compared with that in women without supplementation. The predicted probability of malformations by the initiation time and duration of FA use was estimated to determine optimal options.

RESULTS

Periconceptional FA supplementation was associated with a lower and insignificant risk of congenital malformations (1.59% vs. 2.37%; odds ratio [OR] 0.69; 95% confidence interval [CI]: 0.44-1.08), heart defects (3.8 vs. 8.0 per 1000 infants; OR, 0.47; 0.21-1.02), and neural tube defects (7.0 vs. 11.5 per 10,000 infants; OR, 0.64; 0.08-5.15). FA use after pregnancy provided greater protection against total malformations. Statistically significant associations were found in women who initiated FA supplementation in the first month of gestation (OR, 0.55; 95% CI: 0.33-0.91) and in those who supplemented for 1 to 2 months (OR, 0.59; 95% CI: 0.36-0.98). Similar results were found for heart defects. The optimal initiation time was 1.5 (optimal range: 1.1 to 1.9) months before pregnancy and a duration of 4.0 (3.7 to 4.4) months was reasonable to achieve the lowest risk of congenital malformations. Heart defect prevention required an earlier initiation (2.2 vs. 1.1 months before pregnancy) and a longer duration (4.7 vs. 3.7 months) than the prevention of other malformations.

CONCLUSIONS

The timely initiation of FA supplementation for gestation was associated with a decreased risk of congenital malformations, which was mainly attributed to its protection against heart defects. The initiation of FA supplementation 1.5 months before conception with a duration of 4 months is the preferred option for congenital malformation prevention.

TRIAL REGISTRATION

Chictr.org.cn identifier: ChiCTR-SOC-17010976.

Dietary Folic Acid Supplementation Attenuates Maternal High-Fat Diet-Induced Fetal Intrauterine Growth Retarded via Ameliorating Placental Inflammation and Oxidative Stress in Rats

The placenta is particularly susceptible to inflammation and oxidative stress, leading to placental vascular dysfunction and placental insufficiency, which is associated with fetal intrauterine growth restriction (IUGR). It is unknown whether folic acid (FA) supplementation can alleviate high-fat diet-induced IUGR in rats by improving placental function. In this study, pregnant rats were randomized into one of four diet-based groups: (1) control diet (CON), (2) control diet supplemented with FA, (3) high-fat diet (HFD), and (4) high-fat diet supplemented with FA (HFD + FA). Dams were sacrificed at gestation day 18.5 (GD18.5). The results indicated that dietary FA supplementation normalized a maternal HFD-induced decrease in fetal weight. The decrease in placental efficiency, labyrinth zone (LZ) area, blood sinusoid area, vascular density, and the levels of angiogenesis factors induced by a maternal HFD were alleviated by the addition of FA, suggesting that FA supplementation can alleviate placental vascular dysplasia. Furthermore, FA supplementation increased the protein expressions of SIRT1, inhibited NF-κB transcriptional activation, attenuated the levels of NF-κB/downstream pro-inflammatory cytokines, induced Nrf2 activation, and increased downstream target protein expression. In conclusion, we found that dietary FA supplementation during pregnancy could improve maternal HFD-induced IUGR by alleviating placental inflammation and oxidative stress, which may be associated with the regulation of SIRT1 and its mediated NF-κB and Nrf2 signaling pathways.

Neural tube defects: a review of global prevalence, causes, and primary prevention

Neural tube defects (NTDs) are common birth defects and contribute to life-long disabilities, high medical care costs, and perinatal and child mortality. This review is a primer on prevalence, causes, and evidence-based prevention strategies for NTDs. The estimated average global prevalence of NTDs is two cases per 1000 births, amounting to approximately 214,000-322,000 affected pregnancies worldwide annually. Prevalence and associated adverse outcomes are disproportionately high in developing countries. NTDs have multiple risk factors including genetic and non-genetic (i.e., maternal nutritional status, pre-pregnancy diabetes, early pregnancy exposure to valproic acid (anti-epileptic medication), and a previous pregnancy affected by a NTD) factors. Maternal folate insufficiency before and during early pregnancy is the most common risk factor and is preventable. Folic acid (vitamin B9) is required for formation of the neural tube early in pregnancy, around 28 days after conception, when most women are unaware of their pregnancies. Current guidelines recommend that all women planning or capable of pregnancy take a daily supplement containing 400-800 μg of folic acid. Mandatory folic acid fortification of staple foods (e.g., wheat flour, maize flour, rice) is safe, economical, and the effective intervention for primary prevention of NTDs. Currently, about 60 countries are implementing mandatory folic acid fortification of staple foods, preventing just a quarter of all preventable NTD cases worldwide. There is an urgent need for active champions, including neurosurgeons and other healthcare providers, to generate political will and promote effective mandatory food fortification with folic acid, and reach equitable primary prevention of NTDs in all countries.

Using a health observance event to raise awareness: An assessment of World Birth Defects Day

World Birth Defects Day (WorldBDDay), observed annually on March 3, was launched in 2015 to advocate for public health surveillance, research, and prevention of birth defects, along with improved care and treatment for affected individuals. Following its fifth observance in 2019, we assessed WorldBDDay by analyzing: (a) engagement and content of over 2000 WorldBDDay posts on Facebook, Twitter, and Instagram; (b) interview responses from 9 WorldBDDay charter (founding) organizations on their perceptions of strengths and areas for improvement for WorldBDDay; (c) survey responses from 61 WorldBDDay 2019 partner (participating) organizations on their WorldBDDay 2019 activities; and (d) post-2019 social media engagement. Most social media posts (60%) occurred from organizations using Twitter (80% vs. 14% for Instagram and 6% for Facebook), although posts from individuals had higher levels of engagement (e.g., likes and comments). The highest engagement occurred for posts focused on general awareness, prevention, or events. Charter organizations reported the need for existing and new partner engagement, including a designated WorldBDDay contact for regular communication and coordination of activities and prepared prevention-focused messaging. Partner organizations reported using the WorldBDDay toolkit, especially key messages and social media tips, and suggested expanding the toolkit with relevant resources. Post-2019 Twitter engagement was lower than 2019 WorldBDDay (peak event) but showed similar reach to WorldBDDay events prior to 2019. Our assessment identified WorldBDDay health observance events as an important tool to support knowledge dissemination and global community engagement around birth defects. Moving forward, engagement with more individuals and organizations may improve the reach of WorldBDDay.