Folate and folic acid in the periconceptional period: recommendations from official health organizations in thirty-six countries worldwide and WHO

Comparative Scoping Review of Prenatal Care Resources for Families of Children With Spinal Dysraphism and Hydrocephalus in High-Income Countries and Low- and Middle-Income Countries

BACKGROUND AND OBJECTIVES

Low- and middle-income countries (LMICs) face higher incidences and burdens of care for neural tube defects (NTDs) and hydrocephalus compared with high-income countries (HICs), in part due to limited access to neurosurgical intervention. In this scoping review, we aim to integrate studies on prenatal care, counseling, and surgical management for families of children with spinal dysraphism and hydrocephalus in LMICs and HICs.

METHODS

PubMed, Embase, Global Index Medicus, and Web of Science electronic databases were searched for English language articles pertaining to prenatal care, counseling, and surgical management for families of children with spinal dysraphism and hydrocephalus in HICs and LMICs. Identified abstracts were screened for full-text review. Studies meeting inclusion criteria were reviewed in full and analyzed.

RESULTS

Seventy studies met the inclusion criteria. Twelve studies (16.9%) were conducted in HICs only, 50 studies (70.4%) were conducted in LMICs only, and 9 studies (12.7%) encompassed both. On thematic analysis, seven underlying topics were identified: epidemiology, folate deficiency and supplementation/fortification, risk factors other than folate deficiency, prenatal screening, attitudes and perceptions about NTDs and their care, surgical management, and recommendations for guideline implementation.

CONCLUSION

NTDs have become a widely acknowledged public health problem in many LMICs. Prenatal counseling and care and folate fortification are critical in the prevention of spinal dysraphism. However, high-quality, standardized studies reporting their epidemiology, prevention, and management remain scarce. Compared with NTDs, research on the prevention and screening of hydrocephalus is even further limited. Future studies are necessary to quantify the burden of disease and identify strategies for improving global outcomes in treating and reducing the prevalence of NTDs and hydrocephalus. Surgical management of NTDs in LMICs is currently limited, but pediatric neurosurgeons may be uniquely equipped to address disparities in the care and counseling of families of children with spinal dysraphism and hydrocephalus.

Spina Bifida Prevention: A Narrative Review of Folic Acid Supplements for Childbearing Age Women

Neural tube defects (NTDs) are malformations that occur during embryonic development, and they account for most central nervous system birth anomalies. Genetic and environmental factors have been shown to play a role in the etiology of NTDs. The different types of NTDs are classified according to anatomic location and severity of the defect, with most of the neural axis anomalies occurring in the caudal spinal or cranial areas. Spina bifida is a type of NTD that is characterized by an opening in the vertebral arch, and the level of severity is determined by the extent to which the neural tissue protrudes through the opened arch(es). Prevention of NTDs by administration of folic acid has been studied and described in the literature, yet there are approximately 300,000 cases of NTDs that occur annually, with 88,000 deaths occurring per year worldwide. A daily intake of at least 400 μg of folic acid is recommended especially for women of childbearing age. To provide the benefits of folic acid, prenatal vitamins are recommended in pregnancy, and many countries have been fortifying foods such as cereal grain products with folic acid; however, not all countries have instituted folic acid fortification programs. The present investigation includes a description of the pharmacology of folic acid, neural tube formation, defects such as spina bifida, and the relevance of folic acid to developing spina bifida. Women's knowledge and awareness of folic acid regarding its importance in the prevention of spina bifida is a major factor in reducing incidence worldwide.

Association between nutrient intake and female infertility: a study based on NHANES database

BACKGROUND

This study was designed to investigate the association between nutrients and female infertility.

METHODS

A cross-sectional study on 18-45 years of age reproductive-age women was conducted using the data from the National Health and Nutrition Examination Surveys (NHANES) for the periods 2013-2014 and 2015-2016. Multivariate logistic regression analysis was performed to evaluate the association between nutrients and female infertility. Subgroup analysis was applied to the body mass index (BMI). Results were summarised using an odds ratio (OR) with a 95% confidence interval (CI).

RESULTS

Of the total 1713 women, 204 women (11.91%) were infertile. The result demonstrated that higher intake of carbohydrate (OR: 0.46, 95% CI: 0.24-0.86, p = 0.018), vitamin A (OR: 0.44, 95% CI: 0.24-0.80, p = 0.009), vitamin C (OR: 0.48, 95% CI: 0.26-0.88, p = 0.020), magnesium (OR: 0.36, 95% CI: 0.17-0.76, p = 0.009), iron (OR: 0.43, 95% CI: 0.23-0.82, p = 0.012), lycopene (OR: 0.55, 95% CI: 0.33-0.91, p = 0.022), and total folate (OR: 0.38, 95% CI: 0.20-0.70, p = 0.003) were associated with a lower risk of female infertility. The subgroup analysis also reported that intakes of vitamin A, vitamin C, and lycopene were related to a lower risk of female infertility among women with a BMI being 18.5-24.9 kg/m2. Among women with BMI > 24.9 kg/m2, high intakes of magnesium, iron and total folate were associated with a decreased risk of female infertility.

CONCLUSIONS

The intake of several nutrients is associated with a decreased risk of female infertility. These findings provide insight into potentially modifiable lifestyle factors associated with female infertility.

Maternal folate and metabolic programming of the offspring: A systematic review of the literature

There is emerging evidence suggesting that folate status during pregnancy may play a role in fetal programming of metabolic disease. Therefore, this systematic review aims to summarize and systematize the current evidence surrounding the relationship between maternal folate status during pregnancy and offspring metabolic programming, focusing on both animal and human studies. PubMed, Web of Science and Scopus databases were searched in order to identify studies conducted on pregnant women or in animals studying the association between maternal folate exposure and at least one metabolic syndrome outcome in offspring after birth (weight, blood pressure, glucose regulation parameters, triglycerides and high-density lipoprotein cholesterol (HDL-C) levels). The quality of included studies was assessed using SYRCLE Risk of Bias Tools for animal studies and NHLBI Study Quality Assessment Tools for observational studies and randomized controlled trials. Among the 10 "good" or "fair" studies that investigated excessive folate exposure during the perigestational period, 7 animal studies and 1 human study reported a positive association with development of metabolic outcomes in offspring. On the other hand, 6 of the 7 "good" or "fair" included human studies compared adequate versus low folate exposure, showing a lack of association (n = 3) or a protective effect (n = 3) regarding offspring's dysmetabolism. In conclusion, there is strong evidence from animal trials suggesting that excessive folate intake in early phases of development programs for metabolic dysfunction. While human evidence regarding excessive maternal folate exposure is currently scarce, human studies suggest that folate adequacy in pregnancy is not detrimental for metabolic function of the offspring.

Impact of Homocysteine as a Preconceptional Screening Factor for In Vitro Fertilization and Prevention of Miscarriage with Folic Acid Supplementation Following Frozen-Thawed Embryo Transfer: A Hospital-Based Retrospective Cohort Study

Homocysteine is an amino acid naturally produced in the body and metabolized via the methionine cycle. High homocysteine levels can increase the risk of infertility and pregnancy complications, such as preeclampsia, preterm delivery, miscarriage, and low birth weight. Preconceptional homocysteine levels may be reduced by taking folic acid supplements to reduce the risk of such complications. This cross-sectional, hospital-based study was conducted to examine the role of homocysteine in 1060 infertile women with a history of IVF/intracytoplasmic sperm injection (ICSI) failure. We analyzed whether folic acid intervention altered homocysteine levels and influenced reproductive outcome. We found that a higher homocysteine level was statistically associated with a lower fertilization rate in patients with a history of IVF/ICSI failure. There was an inverse relationship between homocysteine levels and serum 25(OH)VD, and a trend towards lower anti mullerian hormone in the group with higher homocysteine levels. This is the first interventional study to identify that folic acid supplementation improved pregnancy outcomes following freeze embryo transfer (FET) in women with a history of FET failure by monitoring the reduction in homocysteine levels. Therefore, folic acid supplementation and homocysteine level monitoring may constitute a novel intervention for improving IVF/ICSI pregnancy outcomes.

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.

Parental Folate Deficiency Inhibits Proliferation and Increases Apoptosis of Neural Stem Cells in Rat Offspring: Aggravating Telomere Attrition as a Potential Mechanism

The effect of maternal folate status on the fetal central nervous system (CNS) is well recognized, while evidence is emerging that such an association also exists between fathers and offspring. The biological functions of telomeres and telomerase are also related to neural cell proliferation and apoptosis. The study aimed to investigate the effect of parental folate deficiency on the proliferation and apoptosis of neural stem cells (NSCs) in neonatal offspring and the role of telomeres in this effect. In this study, rats were divided into four groups: maternal folate-deficient and paternal folate-deficient diet (D-D) group; maternal folate-deficient and paternal folate-normal diet (D-N) group; maternal folate-normal and paternal folate-deficient diet (N-D) group; and the maternal folate-normal and paternal folate-normal diet (N-N) group. The offspring were sacrificed at postnatal day 0 (PND0), and NSCs were cultured from the hippocampus and striatum tissues of offspring for future assay. The results revealed that parental folate deficiency decreased folate levels, increased homocysteine (Hcy) levels of the offspring's brain tissue, inhibited proliferation, increased apoptosis, shortened telomere length, and aggravated telomere attrition of offspring NSCs in vivo and in vitro. In vitro experiments further showed that offspring NSCs telomerase activity was inhibited due to parental folate deficiency. In conclusion, parental folate deficiency inhibited the proliferation and increased apoptosis of offspring NSCs, maternal folate deficiency had more adverse effects than paternal, and the mechanisms may involve the telomere attrition of NSCs.

Variations in folate prescriptions for patients with the MTHFR genetic polymorphisms: A case series study

Background

Over 48.5 million couples are reported with infertility worldwide. Health policy recommends folic acid in women of childbearing age, particularly in preconception and pregnancy which results in women purchasing over-the-counter prenatal multivitamins containing folic acid through pharmacies and other retail outlets. Emerging studies are investigating whether other forms of supplemental folate are more suitable, particularly for those with methylenetetrahydrofolate reductase (MTHFR) polymorphisms. This case series aimed to document variations in forms and dosage of folate prescribed by Australian practitioners to patients with diagnosed infertility and MTHFR polymorphisms.

Methods

Australian practitioners were invited to complete a retrospective case report form for patients that presented with unexplained infertility. This case report form documented the form and dose of folate that practitioners were prescribing to their infertility patient with MTHFR polymorphisms, together with their fertility history.

Results

Six practitioners submitted case information for 12 patients with diagnosed infertility and MTHFR polymorphisms. All patients had been advised by their practitioner to remove folic acid in supplemental form and were prescribed 5-methyltetrahydrofolate (5-MTHF) or a combination of 5-MTHF and folinic acid, at higher doses than the Australian recommended dose (mean daily maximum prescribed dose: 2325μg). Eleven patients conceived within the treatment period (average treatment of one year) and ten were reported as having a live birth.

Conclusion

This case series has highlighted clinical practices that vary from the recommendations by Australian policy. Further research is required to verify the clinical importance of variations in folate prescriptions for women with MTHFR polymorphisms and how folate recommendations may need to change depending on these polymorphisms. This has direct relevance to those prescribing at the pharmacy and retail level, specifically pharmacists and pharmacy assistants.

The association between serum folate and gestational diabetes mellitus: a large retrospective cohort study in Chinese population

OBJECTIVE

To investigate the association between folate levels and the risk of gestational diabetes mellitus (GDM) risk during the whole pregnancy.

DESIGN

In this retrospective cohort study of pregnant women, serum folate levels were measured before 24 gestational weeks (GW). GDM was diagnosed between 24th and 28th GW based on the criteria of the International Association of Diabetes and Pregnancy Study Groups. General linear models were performed to examine the association of serum folate with plasma glucose (i.e. linear regressions) and risk of GDM (i.e. log-binomial regressions) after controlling for confounders. Restricted cubic spline regression was conducted to test the dosage-response relationship between serum folate and the risk of GDM.

SETTING

A sigle, urban hospital in Shanghai, China.

PARTICIPANTS

A total of 42 478 women who received antenatal care from April 2013 to March 2017 were included.

RESULTS

Consistent positive associations were observed between serum folate and plasma glucose levels (fasting, 1-h, 2-h). The adjusted relative risks (RR) and 95 % CI of GDM across serum folate quartiles were 1·00 (reference), 1·15 (95 % CI (1·04, 1·26)), 1·40 (95 % CI (1·27, 1·54)) and 1·54 (95 % CI (1·40, 1·69)), respectively (P-for-trend < 0·001). The positive association between serum folate and GDM remained when stratified by vitamin B12 (adequate v. deficient groups) and the GW of serum folate measurement (≤13 GW v. >13 GWs).

CONCLUSIONS

The findings of this study may provide important evidence for the public health and clinical guidelines of pregnancy folate supplementation in terms of GDM prevention.

Knowledge of periconceptional folic acid supplementation and associated factors among pregnant women attending antenatal care at public health facilities in Hawassa, South Ethiopia

BACKGROUND

Neural tube closure defect (NTD) such as spinal bifida and anencephaly are serious neurological disabilities that occur when the neural tube does not close completely within 28 days of conception. Even though Folic acid supplementation during and before pregnancy is proved to significantly reduces the risk of NTDs. Currently only 23% of folic acid preventable NTD achieved Worldwide; mainly due to lack of awareness about folic acid supplementation. This study was aimed to assess the knowledge of Folic acid supplementation among pregnant women attending antenatal care at public health facilities in Hawassa Ethiopia.

METHODS

Institution based cross-sectional study was employed among 358 pregnant women attending antenatal care. Data were collected using an interviewer-administered structured questionnaire and analyzed using SPSS version 22. The knowledge of Folic acid supplementation was assessed using six multiple-choice questions. The association between the dependent and independent variables were analyzed using Binary Logistic regression model and statistically significant predictors at p-value <.05 at 95% CI.

RESULTS

This study indicated that only 7.5% (95% CI, 5.3-10.1) of pregnant women had good knowledge of Folic acid supplementation. The pregnant women who had a history of at least one previous pregnancy loss AOR = 12.64 (95% CI: 4.98, 32.08) and those who had preconception consultation AOR = 11.77 (95% CI: 3.01, 46.07) were more likely to have good knowledge of periconceptional folic acid supplementation as compared to their counterpart.

CONCLUSIONS

The knowledge of periconceptional folic acid supplementation among pregnant women was worryingly low in the study area. Alternative and more effective strategies are needed if the population of Ethiopia is to benefit fully from the folic acid prevention of NTDs. Thus, in Ethiopia the future strategies should focus on the possible way to reach the last group through fortification of staple foods with folic acid along with improving women's awareness on folic acid importance in reducing Neural tube defects.

Joint effect of maternal pre-pregnancy body mass index and folic acid supplements on gestational diabetes mellitus risk: a prospective cohort study

Background

The joint effect of folic acid (FA) supplements and maternal pre-pregnancy body mass index (BMI) on gestational diabetes mellitus (GDM) has not been fully addressed. This study aimed to examine the joint effect of FA supplements and pre-pregnancy BMI on GDM.

Methods

Pregnant women at 4 to 14 weeks of gestation (n = 3186) were recruited during their first prenatal visit in Qingdao from May 1, 2019, to June 27, 2021. The main outcome was GDM at 24–28 weeks’ gestation. Screening was based on 75 g 2-hour oral glucose tolerance (OGTT), a fasting glucose ≥ 5.1 mmol/L, or a 1-hour result ≥ 10.0 mmol/L, or a 2-hour result ≥ 8.5 mmol/L. The interactive effect of FA supplements and pre-pregnancy BMI on GDM was examined using logistic regression analysis and ratio of odds ratios (ROR) was used to compare subgroup differences.

Results

Overall, 2,095 pregnant women were included in the analysis, and GDM incidence was 17.76%. Compared with women with pre-pregnancy BMI lower than 25.0 kg/m² and FA-Sufficient supplements ≥ 400 µg/day (FA-S) population, the adjusted odds ratios (aORs) of FA-S and FA-Deficiency supplements < 400 µg/d (FA-D) were 3.57 (95% confidence interval [CI]: 2.02–6.34) and 10.82 (95% CI: 1.69–69.45) for the obese women (BMI ≥ 30.0 kg/m²), and the aORs of FA-S and FA-D were 2.17 (95% CI: 1.60–2.95) and 3.27 (95% CI: 1.55–6.92) for overweight women (25.0 kg/m² ≤ BMI < 30.0 kg/m²). However, the risk of GDM did not differ significantly between the FA-D and the FA-S group in pre-pregnancy obese women (ROR = 2.70, 95%CI: 0.47–2.30), or overweight women (ROR = 0.66, 95%CI: 0.30–1.49). After further stratification of FA supplementation time, F-D and FA-S in obese women showed an interaction when FA supplement intake time < 3 months. However, there was no significant difference between subgroups (ROR = 1.63, 95% CI: 0.37–7.04).

Conclusion

Maternal pre-pregnancy BMI was associated with the incidence of GDM, the dose of FA supplementation from pre-pregnancy to early pregnancy was not found to be related to the incidence of GDM. The dosage of FA supplement was not associated with GDM irrespective of maternal pre-pregnancy BMI.

Investigating continuation of folic acid supplementation during peri-conceptional period: a community-based cross-sectional study

BACKGROUND

Maternal folate may not reach an optimal level to prevent neural tube defects if supplementation commenced post-conception or took place pre-conception only. Our study aimed to investigate the continuation of folic acid (FA) supplementation from pre-conception to post-conception during peri-conceptional period and to examine its differences in FA supplementation between the subgroups taking the initiation timing into consideration.

METHODS

This study was conducted in two community health service centers in Jing-an District of Shanghai. Women accompanying their children to pediatric health clinics of the centers were recruited and asked to recall information concerning their socioeconomic and previous obstetric characteristics, utilization of healthcare and FA supplementation before and/or during pregnancy. The continuation of FA supplementation during peri-conceptional period were categorized into three subgroups: Supplementing with FA pre- and post-conception; supplementing with FA preconception only or post-conception only; no FA supplements pre-conception and post-conception. The relationship between FA continuation and couples' characteristics were examined as setting the first subgroup as the base reference.

RESULTS

Three hundred and ninety-six women were recruited. Over 40% of the women started FA supplementation after conception and 30.3% of them supplemented with FA from pre-conception to the first trimester of their pregnancy. Compared to this one-third of participants, women who didn't supplemented with any FA during peri-conceptional period were more likely to have no utilization of pre-conception healthcare ([Formula: see text]= 2.47, 95% [Formula: see text]: 1.33-4.61) or antenatal care ([Formula: see text]= 4.05, 95% [Formula: see text]: 1.76-9.34), or who had a lower family socioeconomic status ([Formula: see text]= 4.36, 95% [Formula: see text]: 1.79-10.64). Women who supplemented with FA pre-conception only or post-conception only were more likely to have no utilization of pre-conception healthcare ([Formula: see text]= 2.94, 95% [Formula: see text]: 1.79-4.82), or to have no previous pregnancy complication ([Formula: see text]=1.80, 95% [Formula: see text]: 0.99-3.28).

CONCLUSION

Over two-fifth of the women started FA supplementation and only one-third of them had an optimal supplementation from pre-conception to the first trimester. Maternal utilization of healthcare before or during pregnancy together with maternal and paternal socioeconomic status may play a role in the continuation to FA supplementation pre- and post-conception.

Maternal gestational diabetes in singleton pregnancies conceived by ART may be modified by periconceptional B vitamins

Background

The risk of maternal gestational diabetes mellitus (GDM) may be influenced by pregnancies conceived through assisted reproductive technology (ART). However, the influence of the dosage of B vitamins (folate, vitamin B6 and vitamin B12) on GDM weren't considered. Thus, we hypothesized that periconceptional B vitamins could modify maternal GDM in singleton pregnancies conceived by ART.

Methods

This study is a prospective cohort study using data from 3,252 women with singleton pregnancies and received a 75 g oral glucose tolerance test (OGTT) at 24-28 weeks of gestation. We included an interaction term in the multivariable logistic and linear regression models, respectively, to test our hypothesis.

Results

Women who underwent ART were significantly associated with the incidence of GDM compared with spontaneous pregnancy women. The adjusted odds ratio (aOR) was 1.59, and the 95% confidence interval (CI) was 1.08-2.34. ART pregnancies also elevated OGTT (oral glucose tolerance test) 1-h blood glucose levels and OGTT 2-h blood glucose levels (P < 0.05). A positive association between dietary vitamin B6 (aOR = 1.60, 95% CI: 1.13-2.27), dietary vitamin B12 (aOR = 1.88, 95% CI: 1.34-2.64) and dietary folate (aOR = 1.66, 95% CI: 1.19-2.32) with GDM risk comparing the highest to the lowest quartile (all P _trend < 0.001). The aORs of GDM for inadequate (< 400 μg/day), adequate (400-800 μg/day), and excessive (> 800 μg/day) supplemental folate intake were 1.00, 0.93, and 1.30, respectively (P _trend = 0.033). Since only the supplemental folate illustrates a statistically significant interaction with ART (P for interaction < 0.05), the association between ART and GDM and OGTT blood glucose levels stratifying by supplemental folate were further evaluated. These increased risks of GDM (aOR = 1.62, 95% CI: 1.39-3.39) and the regression coefficients (β) of 1-h blood glucose (β = 0.76, 95% CI: 0.39-1.13) and 2-h blood glucose (β = 0.60, 95% CI: 0.29-0.92) in the multiple linear regression model were significant only in the ART group with excessive supplemental folate (> 800 μg/day).

Conclusion

The risk of GDM is significantly elevated, particularly among those women who conceived ART with the intake of excessive supplemental folate (> 800 μg/day).

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.

An evaluation of adherence to folic acid supplementation in pregnant women during early gestation for the prevention of neural tube defects

OBJECTIVE

Neural tube defects (NTD) are potentially preventable by periconceptual folic acid supplementation. Women with obesity are at higher risk of NTD, therefore, are recommended a higher dose of 5 mg folic acid to mitigate this risk. The aim of this study was to evaluate maternal practice of folic acid supplementation amongst the antenatal population in relation to maternal obesity status.

DESIGN

Prospective observational study.

SETTING

Women ≤18 weeks' gestation at their first antenatal appointment attending University Maternity Hospital Limerick (Ireland) were recruited. Maternal height and weight were measured. Obesity was defined at a threshold of ≥30·0 kg/m² and ≥27·5 kg/m² when adjusting for ethnicity. A two-part questionnaire captured maternal characteristics and assessed supplementation compliance, commencement and dosage. Fisher's exact test for independence analysed differences in variables. A P value of <0·05 was considered significant.

PARTICIPANTS

A total of 328 women participated over a duration of 6 weeks.

RESULTS

Mean gestational age was 12·4 ± 1·4 weeks and mean BMI 26·7 kg/m² ± 5·2 kg/m². 23·8 % (n 78) were classified as obese. 96·5 % (n 315) were taking folic acid and 95·7 % (n 314) supplemented daily. 30·2 % (n 99) commenced supplementation 12 weeks prior to conception. Overall, 57·9 % (n 190) of women met folic acid supplementation dose requirements. 89·1 % (n 55) of women with obesity did not. Women with obesity were less likely to meet the higher folic acid supplementation dose requirements (P =< 0·001).

CONCLUSION

Folic acid supplementation practices within this cohort were suboptimal to prevent their risk of NTD. This study showed inadequate compliance of folic acid supplementation, and inadequate dosage for women with obesity. Increased patient education and awareness are needed within the antenatal period of pregnancy to bring folic acid supplementation practices in line with best practice guidelines.

Periconceptional Mediterranean diet during pregnancy on children's health

During pregnancy, rapid and subtle physiological changes are observed from conception to birth. Nutrition and other lifestyle factors before and during pregnancy have been shown in the literature to influence the health of both mother and child. A healthy and varied diet during pregnancy can provide adequate energy and nutrients for both the mother and the growing fetus. Current research focuses on the periconceptional phase, which includes the early processes of gametogenesis, embryogenesis and placentation. A variety of abnormalities and pregnancy-related problems occur during this period, including congenital defects, fetal loss, miscarriage and preterm birth. A varied and balanced diet during periconception is important to maintain fetal development and growth. To date, numerous studies have been conducted to investigate the effects of consuming different nutrients, foods or food groups during pregnancy on the health of mother and child. For example, the Mediterranean diet is considered as a balanced, nutrient-rich diet due to the low consumption of meat products and fatty foods and the high consumption of vegetables, cheese, olive oil, fish, shellfish and little meat. While many studies have been conducted in the literature to investigate the effects of a Mediterranean diet during pregnancy on fetal health, the results have been inconclusive. The aim of this article is to review the current literature on the Mediterranean diet during pregnancy.

Folate supplementation as a strategy to reduce Neural Tube Defects

Folic acid is a vitamin known to prevent neural tube defects, megaloblastic anaemia, cardiovascular morbidity and mortality, etc. The main natural sources of folate are plant and vegetables e.g. green leafy vegetables, broccoli, asparagus, citrus fruits (orange, strawberry), beans, nuts, cauliflowers, beets, corn etc. and meat products like liver. The primary function of folate is its contribution in the synthesis and repair of the DNA. The bioavailability of food folate is approximately 50%. The bioavailability of folic acid taken with meal compared to with water on empty stomach is 85% and 100% respectively.(1) Hence, it is easier to achieve the recommended daily allowances with fortified food as compared to natural food due to higher stability and bioavailability of synthetic folate when compared to natural food.(2)

Maternal Folic Acid Supplementation, Dietary Folate Intake, and Low Birth Weight: A Birth Cohort Study

Objectives

To investigate the independent and collective effects of maternal folic acid supplementation or dietary folate intake on the risk of low birth weight (LBW), and to further comprehensively examine the joint associations of folic acid supplementation and dietary folate intake with LBW by various clinical subtypes.

Design

Participants were recruited from Gansu Provincial Maternity and Child Care Hospital. A standardized and structured questionnaire was distributed to collect demographic factors, reproductive and medical history, occupational and residential history, physical activity, and diet. Data on pregnancy-related complications and birth outcomes were extracted from medical records. Unconditional logistic regression models were used to estimate the odds ratio (OR) and 95% confidence interval (95% CI) for single and joint associations of folic acid supplementation and dietary folate intake with LBW.

Setting

A birth cohort data analysis using the 2010–2012 Gansu Provincial Maternity and Child Care Hospital in Lanzhou, China.

Participants

In total, 9,231 pregnant women and their children were enrolled in the study.

Results

Compared with non-users, folic acid supplementation was associated with a reduced risk of LBW (OR: 0.80, 95% CI: 0.66–0.97), and the reduced risk was mainly seen for term-LBW (OR: 0.59, 95% CI: 0.41–0.85), and multiparous-LBW (OR: 0.72, 95% CI: 0.54–0.94). There were no significant associations between dietary folate intake and LBW, and there was no interaction between folic acid supplement and dietary folate intake on LBW.

Conclusions

Our study results indicated that folic acid supplementation was associated with a reduced risk of LBW, and there was no interaction between folic acid supplements and dietary folate intake on LBW.

Early Life Stage Folic Acid Deficiency Delays the Neurobehavioral Development and Cognitive Function of Rat Offspring by Hindering De Novo Telomere Synthesis

Early life stage folate status may influence neurodevelopment in offspring. The developmental origin of health and disease highlights the importance of the period of the first 1000 days (from conception to 2 years) of life. This study aimed to evaluate the effect of early life stage folic acid deficiency on de novo telomere synthesis, neurobehavioral development, and the cognitive function of offspring rats. The rats were divided into three diet treatment groups: folate-deficient, folate-normal, and folate-supplemented. They were fed the corresponding diet from 5 weeks of age to the end of the lactation period. After weaning, the offspring rats were still fed with the corresponding diet for up to 100 days. Neurobehavioral tests, folic acid and homocysteine (Hcy) levels, relative telomere length in brain tissue, and uracil incorporation in telomere in offspring were measured at different time points. The results showed that folic acid deficiency decreased the level of folic acid, increased the level of Hcy of brain tissue in offspring, increased the wrong incorporation of uracil into telomeres, and hindered de novo telomere synthesis. However, folic acid supplementation increased the level of folic acid, reduced the level of Hcy of brain tissue in offspring, reduced the wrong incorporation of uracil into telomeres, and protected de novo telomere synthesis of offspring, which was beneficial to the development of early sensory-motor function, spatial learning, and memory in adolescence and adulthood. In conclusion, early life stage folic acid deficiency had long-term inhibiting effects on neurodevelopment and cognitive function in offspring.

Maternal micronutrient status and its association with sociodemographic, maternal, and dietary factors in a cross-sectional study

AIM

Maternal serum micronutrient status can have a significant impact on short- and long-term outcomes for mother and offspring. The aim of this study was to examine the associations of maternal serum folate, ferritin, and vitamin B₁₂ status with maternal and dietary factors.

METHODS

This observational cross-sectional study was carried out with 165 healthy pregnant women at least 18 years of age with a singleton pregnancy. Maternal nutrient intake was determined by 24-hour dietary recall method and supplement records. Multivariable analyses using stepwise linear regression models were performed to associations of dietary intakes and maternal serum status.

RESULTS

There was a difference between the lowest and highest quartile of maternal serum folate, ferritin, and vitamin B₁₂ status and maternal characteristics and dietary, and total intakes of nutrients (p < 0.05). Multivariable stepwise linear regression analysis showed the predictors of serum folate status were dietary folate equivalent, dietary folate, total vitamin B₆ and iron intake. Primer predictors of serum ferritin and vitamin B₁₂ status were dietary protein intake (p < 0.05).

CONCLUSION

Our findings support existing recommendations that folic acid supplementation should be prescribed to achieve optimal serum folate status during pregnancy. However, dietary protein intake is important to provide optimal maternal serum vitamin B₁₂ and ferritin status.

Associations of Maternal rs1801131 Genotype in MTHFR and Serum Folate and Vitamin B12 with Gestational Diabetes Mellitus in Chinese Pregnant Women

Circumstantial evidence links one-carbon metabolism (OCM) related nutrients, such as folate and vitamin B₁₂, with gestational diabetes mellitus (GDM). However, few studies have evaluated the combined effects of these nutrients with OCM related gene polymorphisms on GDM. This study investigated whether OCM related genetic variants modified the associations of folate and B₁₂ with GDM. Logistic regression was used to estimate odds ratios (ORs) for OCM related nutrients and single nucleotide polymorphisms (SNPs) in genes encoding main OCM related enzymes (MTHFR, MTR, and MTRR) on GDM. Higher folate concentrations were associated with increased GDM risk (OR: 1.59; 95% CI: 1.22, 2.13). However, higher B₁₂ concentrations were associated with reduced GDM risk (OR: 0.76; 95% CI: 0.65, 0.92). Pregnancies with MTHFR rs1801131 G alleles had a significantly lower risk of GDM than pregnancies with T alleles (OR: 0.65; 95% CI: 0.47, 0.91) under the dominant model. The genotype-stratified analysis revealed the association between folate and GDM (OR: 1.66, 95% CI: 1.20, 2.30) or B₁₂ and GDM (OR: 0.80, 95% CI: 0.65, 0.98) was more evident in pregnancies with TT genotype. Higher folate and lower B₁₂ are associated with GDM. Pregnancies with MTHFR rs1801131 TT genotype are more susceptible to OCM nutrient-related GDM.

Association of the Serum Folate and Total Calcium and Magnesium Levels Before Ovarian Stimulation With Outcomes of Fresh In Vitro Fertilization Cycles in Normogonadotropic Women

Background

Women of reproductive age are recommended to consume folic acid and other supplements before conception and during pregnancy. We aimed to investigate the association of the serum folate and total magnesium (Mg) and calcium (Ca) levels before ovarian stimulation with the outcomes of assisted reproductive technology (ART) in normogonadotropic women.

Methods

We used a subanalysis of data obtained from a multicentre, randomized prospective study (NCT03088137). A total of 110 normogonadotropic, non-advanced aged, non-obese women with tubal and/or male infertility factors were enrolled for the single fresh ovarian stimulation GnRH antagonist cycle. The main outcome measures were the total oocyte yield, mature oocytes, fertilization rate, biochemical, clinical pregnancy, and live birth. Multivariable generalized linear models adjusted for covariates were used with a Poisson distribution and the log link function for adjusted oocyte counts, and a binomial distribution and the log link function were used for adjusted clinical ART outcomes.

Results

The medians (interquartile range (IQR)) were as follows: baseline serum folate, 20.55 ng/ml (10.8, 32.9); Mg, 19.4 mg/L (18.7, 20.7); Ca, 94 mg/L (91.2, 96.4); and Ca/Mg ratio, 4.78 (4.55, 5.02). Women with higher serum folate concentrations (Q4≥33.0 ng/ml) had significantly lower total numbers of oocytes retrieved (adjusted mean (95% CI) 9.2 (7.6-11.3) vs 12.9 (10.9-15.4, p-trend=0.006)) and lower odds ratios (ORs) (95% CI) of 0.12 (0.02, 0.79) for clinical pregnancy and 0.10 (0.01, 0.70) for live birth compared with women in the lowest quartile (<10.8 ng/ml), all p-trend<0.001. Women in the highest Ca/Mg ratio quartile (≥5.02) had ORs (95% CI) of 6.58 (1.31, 33.04) for biochemical pregnancy, 4.85 (1.02, 23.08) for clinical pregnancy and 4.07 (0.83, 19.9) for the live birth rate compared with women in the lowest quartile (<4.55), all p-trend<0.001.

Conclusions

Using multivariable models, we suggested that a baseline elevated serum folate level (≥33.0 ng/ml) and a lower Ca/Mg ratio were associated with worse ART outcomes in normogonadotropic women. Our findings might be useful for choosing safe dosages of folate, calcium, magnesium and complex supplementation for both fertile women and women undergoing infertility treatment. Further preconception large-scale studies with known micro- and macronutrient statuses of both parents and serum folate, Ca, Mg, and hormone levels, are needed.

Folic acid supplementation during pregnancy alters behavior in male rat offspring: nitrative stress and neuroinflammatory implications

Pregnancy diet can impact offspring's neurodevelopment, metabolism, redox homeostasis, and inflammatory status. In pregnancy, folate demand is increased due to the requirement for one-carbon transfer reactions. The present study was proposed to investigate the effect of folic acid supplementation throughout pregnancy on a battery of behavior tests (olfactory preference, motor activity, exploratory capacity, habituation, memory, anxiety- and depression-like behavior). Redox homeostasis and neuroinflammatory status in cerebral cortex were also investigated. After pregnancy confirmation, the pregnant rats were randomly divided into two groups, according to the diet: group 1, (control) standard diet (2 mg/kg diet of folic acid) and group 2, supplemented diet with 4 mg/kg diet of folic acid. Throughout the gestational period, the pregnant rats received experimental diets. Results show that the supplemented diet with 4 mg/kg diet of folic acid throughout pregnancy impaired memory and motricity of the offspring when compared with control (standard diet). It was also observed an increase in anxiety- and depression-like behavior in this group. Nitrite levels increased in cerebral cortex of the offspring, when compared to control group. In contrast, iNOS expression and immunocontent were not altered. Moreover, we identify an increase in TNF-α, IL-1β, IL-6, IL-10, and MCP-1 gene expression in the cerebral cortex. In conclusion, our study showed that the supplemented diet with 4 mg/kg diet of folic acid throughout pregnancy may cause behavioral and biochemical changes in the male offspringGraphical abstract After pregnancy confirmation, the pregnant rats were randomly divided into two groups, according to the diet: group 1, (control) standard diet (2 mg/kg diet of folic acid) and group 2, supplemented diet with 4 mg/kg diet of folic acid. Throughout the gestational period, the pregnant rats received experimental diets. Results show that folic acid supplementation did not impair the mother-pup relationship. We showed that supplemented diet with 4 mg/kg diet of folic acid during pregnancy impairs memory and motricity of the offspring when compared with standard diet. It was also observed an increase in anxiety- and depression-like behavior in this group. Nitrative stress and neuroinflammation parameters were increased in the cerebral cortex of the offspring. ROS, reactive oxygen species.

Relationship between maternal folic acid supplementation during pregnancy and risk of childhood asthma: Systematic review and dose-response meta-analysis

Growing evidence suggests that maternal folic acid supplementation during pregnancy may be associated with the risk of childhood asthma, but these findings remain controversial. Therefore, the purpose of this systematic review and meta-analysis was to assess the association between maternal folic acid supplementation during pregnancy and the risk of childhood asthma, and to determine the safe dose of folic acid supplementation during pregnancy based on a dose-response analysis to lower the risk of childhood asthma. The PubMed, Embase, Cochrane Library, and Web of Science databases were searched for relevant studies published before April 2022. The Newcastle-Ottawa Scale (NOS) was used to evaluate the quality of eligible studies, and a fixed-effect model was employed to calculate the odds ratio (OR) of asthma with 95% confidence intervals (CI). In addition, the generalized least-squares trend (GLST) was used to explore a nonlinear dose-response relationship. Stata 15.0 was used for the statistical analysis mentioned above. This systematic review included 18 studies (13 cohort studies, 5 case-control studies) with a total of 252,770 participants, 50,248 of whom were children with asthma. The meta-analysis showed that maternal folic acid supplementation during pregnancy was significantly associated with the risk of childhood asthma (OR = 1.07; 95% CI = 1.04-1.11). The subgroup analysis revealed a significant correlation between the risk of childhood asthma and the folic acid supplementation in the first Trimester (OR = 1.09; 95% CI = 1.05-1.12), the third Trimester (OR = 1.15; 95% CI = 1.04-1.26) and the whole pregnancy (OR = 1.13; 95% CI = 1.10-1.16). At the same time, the dose-response analysis showed a nonlinear relationship between maternal folic acid intake during pregnancy and the risk of childhood asthma. The risk of asthma in children significantly increased when maternal folic acid intake reached 581 μg/day. This meta-analysis showed that maternal folic acid supplementation during pregnancy increased the risk of asthma in children. Based on the results of the dose-response analysis, less than 580 μg folic acid per day is advised in order to effectively prevent birth defects without increasing the risk of childhood asthma. Systematic Review Registration: https://www.crd.york.ac.uk/prospero/display_record.php?, identifier: CRD42022332140.

Consumption of dietary folate estimates and its implication for reproductive outcome among women of reproductive age in Kersa: cross-sectional survey

Background

Dietary folate inadequacy is one the most common micronutrient deficiencies that cause neural tube defect (NTD) among infants in Sub-Saharan African countries. This study aims to determine the dietary intake of folate among women of reproductive age (WRA) of Kersa, Eastern Ethiopia.

Methods

A cross-sectional study took place among voluntary women that were selected from 1140 random households. Using a validated Food Frequency Questionnaire, participant’s weekly dietary intake history of Ethiopian foods and dietary folate intake was worked out. Statistical analysis was done at a 95% confidence interval. Modified Poisson regression was used to identify factors associated with dietary folate consumption.

Result

The estimated median usual intake of folate was 170 μg/d (IQR: 118.3; 252.2) and about 33% of WRA had low folate intake and 73.9% were at risk for folate inadequacy. From the reported food groups, Beans and Peas, Starchy staples, and Vitamin-A rich dark-green leafy vegetables were the top three ranked foods that contributed much of the dietary folate. The following conditions were statistically related to dietary folate inadequacy; women’s age, being in poor wealth index, low dietary diversity, having seasonal employment, and reliance on market food sources.

Conclusions

We found that women’s dietary intake of folate in Kersa is very low and cannot protect their offspring from the risk of having NTD. They could also potentially be predisposed to poor health outcomes. Diversifying and fortification of Ethiopian wheats and salts could decrease the burden of folate deficiency in the country.

Association of maternal pre-pregnancy dietary intake with adverse maternal and neonatal outcomes: A systematic review and meta-analysis of prospective studies

This study aimed to summarize the evidence regarding the effects of dietary intake before conception on pregnancy outcomes by performing a systematic review and meta-analysis of prospective studies. Electronic databases were searched from inception up to August 2021. Overall, 65 studies involving 831 798 participants were included and 38 studies were quantitatively pooled. With regard to maternal outcomes, pre-pregnancy intake of fried food, fast food, red and processed meat, heme iron and a low-carbohydrate dietary pattern was positively associated with the risk of gestational diabetes mellitus (GDM) (all P < 0.05). However, a high dietary fiber intake and folic acid supplementation were negatively associated with GDM risk (both P < 0.05). With regard to neonatal outcomes, maternal caffeine intake before pregnancy significantly increased the risk of spontaneous abortion, while folic acid supplementation had protective effects on total adverse neonatal outcomes, preterm birth, and small-for-gestational age (SGA, all P < 0.05). However, no significant associations were found between adverse pregnancy outcomes (i.e., GDM and SGA) and the pre-pregnancy dietary intake of sugar-sweetened beverages, potato, fish, and carbohydrates and the Healthy Eating Index. Our study suggests that maintaining a healthy diet before conception has significant beneficial effects on pregnancy outcomes.Supplemental data for this article is available online at https://doi.org/10.1080/10408398.2021.1989658.

Dietary Supplements for Female Infertility: A Critical Review of Their Composition

Infertility is the condition of about 15% of couples that cannot get a conception after one year of unprotected sexual intercourse. In females, the reduced reproductive capacity underlies the most varied causes. Dietary supplements (DS) might be used to improve the pregnancy rate and a wide range of DS are proposed today to support female fertility. Although many authors demonstrated the positive effect of some of these products, the real efficacy of this approach is still debated. In order to evaluate the potential efficacy of DS for female infertility, we analysed the products marketed in Italy, using an original approach. A review of literature was performed to evaluate the effect of nutraceuticals on various female reproductive outcomes and to detect the minimal effective daily dose (mED) able to improve at least one of these. Thereafter, we conceived a formula to classify the expected efficacy of each DS. Each DS was scored and included into three classes of expected efficacy: higher, lower, and none. Ten out of 24 supplements (41.7%) resulted in the higher and 8 (34.3%) in the lower efficacy group, the remaining 6 DS (25.0%) were expected to have no efficacy. DS marketed in Italy are usually blends of many substances that are frequently employed at a negligible dose or without any evidence of efficacy. These findings raise serious doubt about the potential effectiveness of most commercial DS for female infertility.

Pharmacokinetics and placental transfer of dolutegravir in pregnancy

Dolutegravir is currently recommended by the WHO as the preferred first-line treatment for all people with HIV, including pregnant women. Estimates indicate that, by 2024, nearly 22 million adults in low- and middle-income countries will have transitioned to dolutegravir-based ART. It is therefore critical that there is a clear appreciation and understanding of the risks that may be associated with in utero exposure to dolutegravir. In this review we consolidate data from studies on dolutegravir and the placenta. The studies have largely focused on the pharmacokinetics and placental transfer of dolutegravir in pregnancy. These include studies on transplacental transfer of dolutegravir, ex vivo placenta perfusion models, physiologically based pharmacokinetic (PBPK) models and animal studies. The data available clearly demonstrate that placental transfer of dolutegravir occurs in moderate to high concentrations. Intracellular placental dolutegravir has been demonstrated in the placental villous tissue. There are limited data suggesting that pregnancy is associated with decreased maternal dolutegravir levels. In addition, PBPK models have great potential in predicting the passage of drugs through the placenta and further contributing towards the elucidation of fetal exposure. The animal studies available demonstrate that in utero dolutegravir exposure can be associated with neural tube defects. Taking into consideration that antiretroviral exposure may be associated with poor placental development or function and increased risk of adverse effects to the fetus, it is crucially important that these risks are evaluated, especially with the rapid scale up of dolutegravir-based ART into national treatment programmes.

Characteristics of pregnant women with diabetes using injectable glucose-lowering drugs in the EVOLVE study

AIMS

To examine clinical parameters, glycemic control, folic acid supplementation, and the presence of other chronic diseases during early pregnancy in the EVOLVE study population (women with pre-existing diabetes treated with injectable glucose-lowering drugs).

METHODS

Cross-sectional baseline evaluation of EVOLVE: an international, multicenter, non-interventional study investigating the safety of injectable glucose-lowering drugs in pregnant women with pre-existing type 1 (T1D) or type 2 diabetes (T2D). Data were collected at enrollment visit interviews before gestational week 16.

RESULTS

In total, 2383 women from 17 mainly European countries were enrolled in the study: 2122 with T1D and 261 with T2D; mean age was 31 and 33 years, and duration of diabetes was 15 and 6 years, respectively. For women with T1D or T2D, 63% and 75%, respectively, received basal and rapid-acting insulin, 36% and 3% rapid-acting insulin only, 0.7% and 14.0% basal insulin only, 0.2% and 5.4% premix insulin, 0.0% and 1.2% injectable glucagon-like peptide-1 receptor agonist treatment without insulin. In women with T1D or T2D, respectively, during early pregnancy, 59% and 62% had HbA_1c <7.0% (53 mmol/mol); 16% and 36% reported not taking folic acid before or during early pregnancy. Overall, >40% of women had ≥1 chronic concomitant condition (predominantly thyroid disease or hypertension). Retinopathy was the most commonly reported diabetic complication. The most commonly reported previous pregnancy complication was miscarriage.

CONCLUSIONS

Baseline data from this large multinational population of women with pre-existing diabetes indicate that sub-optimal glycemic control, poor pregnancy planning, and chronic concomitant conditions were common in early pregnancy.

Association between maternal folate status and gestational diabetes mellitus

Studies on the association between maternal folate status and gestational diabetes mellitus (GDM) have yielded inconsistent results. This meta-analysis was performed to determine whether there may exist some association between maternal folate status and GDM. Unrestricted searches of PubMed, Web of Science, Cochrane, and Embase were conducted. All relevant studies on the association between maternal folat status and GDM risk were screened. The standardized mean difference (SMD) with 95% CIs was used to determine the association between maternal folate and GDM. Odds ratios (ORs) with 95% confidence intervals (CIs) were calculated using random-effects models to assess the impact of maternal folate status on GDM risk. 12 studies were included. The overall data revealed that compared with the non-GDM group, women with GDM had higher level of folate (SMD 0.41, 95% CI 0.07 to 0.21, I2  = 17.2%) in second or third trimester. We also found that maternal high folate status may be associated with increased risk of GDM (OR 2.16, 95% CI 1.70 to 2.74, I2  = 0.0%). Compared with non-GDM group, women with GDM are prone to higher folate level. Moreover, high maternal folate status may predict a higher risk of GDM. As the number of included studies was limited, further large population studies are needed in the future.

Folic acid supplementation during oocytes maturation influences in vitro production and gene expression of bovine embryos

Embryos that are produced in vitro frequently present epigenetic modifications. However, maternal supplementation with folic acid (FA) may improve oocyte maturation and embryo development, preventing epigenetic errors in the offspring. We sought to evaluate the influence of FA supplementation during in vitro maturation of grade I (GI) and grade III (GIII) bovine oocytes on embryo production rate and the expression of IGF2 and KCNQ1OT1 genes. The oocytes were matured in vitro with different concentrations of FA (0, 10, 30 and 100 μM), followed by in vitro fertilization and embryo culture. On the seventh day (D7) of culture, embryo production was evaluated and gene expression was measured using real-time qPCR. Supplementation with 10 μM of FA did not affect embryo production for GI and GIII oocytes. Moderate supplementation (30 μM) seemed to be a positive influence, increasing embryo production for GIII (P = 0.012), while the highest dose (100 μM) reduced embryo production (P = 0.010) for GI, and IGF2 expression was not detected. In GIII, only embryos whose oocyte maturation was not supplemented with FA demonstrated detected IGF2 expression. The lowest concentration of FA (10 μM) reduced KCNQ1OT1 expression (P = 0.05) on embryos from GIII oocytes. Different FA concentrations induced different effects on bovine embryo production and gene expression that was related to oocyte quality. Despite the epigenetic effects of FA, supplementation seems to be a promising factor to improve bovine embryo production if used carefully, as concentration is an important factor, especially in oocytes with impaired quality.

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.

StudentKost: a cross-sectional study assessing college students' diets: reason for concern?

College students constitute a significant proportion of the young adult population in Norway. They are in their reproductive years, which is of interest regarding diet and preconception health. Our objective was to assess young college students' diet and nutrient intake in relation to national dietary recommendations and assess the probability of inadequate micronutrient intake for both genders using the Nordic Nutrition Recommendations, and also to evaluate its consequences on preconception health and create a groundwork for future interventions on this group. At the University of Agder (UiA), we enrolled 622 students aged 18-40 years for a cross-sectional study of student's diet, StudentKost. The students completed a food frequency questionnaire, including questions of supplement use, over the past 4 weeks. Intake of fruits, vegetables, oily fish, and whole grain was lower than recommended, as were mean intake of folate, iron, and iodine. Our main findings are that students have a somewhat suboptimal diet compared to the Norwegian dietary guidelines. Male students had generally lower diet quality than females. Compared to the Nordic Nutrition Recommendations (NNR), we also saw a relatively high probability of inadequate intake of several micronutrients and a very high probability for some micronutrients in a significant portion of the sample. Public health effort should be directed towards improving students and young adults' diet in general, and interventions towards improving preconception health should be explored. The low participation rate limits the generalizability of our findings. Our findings encourage further investigation into young adults' diet.

Folic acid supplementation is associated with size at birth in the Screening for Pregnancy Endpoints (SCOPE) international prospective cohort study

BACKGROUND

Small-for-gestational-age (SGA) is a significant cause of morbidity and mortality, and there are currently few preventive strategies.

AIM

The aim of this study was to investigate the relationship between maternal folic acid supplement (FAS) use pre-conception through to the second trimester, and small-for-gestational age (SGA) and birth size parameters.

STUDY DESIGN

Women were recruited as part of the Screening for Pregnancy Endpoints (SCOPE) international prospective multi-centre cohort study: New Zealand, Australia, United Kingdom and Ireland. Information on FAS use pre-conception, during the first trimester and at 15 ± 1 weeks' gestation was collected via interview administered questionnaire. Participants were followed through to delivery. Pregnancy outcome data and birth measurements were collected within 72 h of birth. Multivariable regression analysis was used to investigate relationships between FAS and outcomes, adjusting for maternal sociodemographic and lifestyle factors.

SUBJECTS

Nulliparous women with singleton pregnancies.

OUTCOME MEASURES

SGA (<10th customised birthweight centile).

RESULTS

5606 women were included. SGA prevalence was 11.3%. Pre-conception FAS was associated with a significantly lower risk of SGA: aOR = 0.82 (95% CI: 0.67-01.00 p = 0.047). Although the association between FAS at 15 weeks' gestation and SGA did not reach significance, FAS at 15 weeks was associated with a significantly higher customised birthweight centile (β 2.56 (95% CI: 0.87-4.26; p = 0.003). There was no significant effect of FAS on large-for-gestational-age births or head circumference.

CONCLUSIONS

In this international cohort, FAS was positively associated with fetal growth, without increasing risks associated with LGA. Further studies are required to confirm whether continuing FAS beyond the first trimester might lower the risk of SGA.

Maternal Folic Acid Supplementation During Pregnancy Promotes Neurogenesis and Synaptogenesis in Neonatal Rat Offspring

Maternal folic acid supplementation during pregnancy is associated with improved cognitive performances in offspring. However, the effect of supplementation on offspring's neurogenesis and synaptogenesis is unknown, and whether supplementation should be continued throughout pregnancy is controversial. In present study, 3 groups of female rats were fed a folate-normal diet, folate-deficient diet, or folate-supplemented diet from 1 week before mating until the end of pregnancy. A fourth group fed folate-normal diet from 1 week before mating until mating, then fed folate-supplemented diet for 10 consecutive days, then fed folate-normal diet until the end of pregnancy. Offspring were sacrificed on postnatal day 0 for measurement of neurogenesis and synaptogenesis by immunofluorescence and western blot. Additionally neural stem cells (NSCs) were cultured from offspring's hippocampus for immunocytochemical measurement of their rates of proliferation and neuronal differentiation. The results demonstrated that maternal folic acid supplementation stimulated hippocampal neurogenesis by increasing proliferation and neuronal differentiation of NSCs, and also enhanced synaptogenesis in cerebral cortex of neonatal offspring. Hippocampal neurogenesis was stimulated more when supplementation was continued throughout pregnancy instead of being limited to the periconceptional period. In conclusion, maternal folic acid supplementation, especially if continued throughout pregnancy, improves neurogenesis and synaptogenesis in neonatal offspring.

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.

Moderate maternal folic acid supplementation ameliorates adverse embryonic and epigenetic outcomes associated with assisted reproduction in a mouse model

STUDY QUESTION

Could clinically-relevant moderate and/or high dose maternal folic acid supplementation prevent aberrant developmental and epigenetic outcomes associated with assisted reproductive technologies (ART)?

SUMMARY ANSWER

Our results demonstrate dose-dependent and sex-specific effects of folic acid supplementation in ART and provide evidence that moderate dose supplements may be optimal for both sexes.

WHAT IS KNOWN ALREADY

Children conceived using ART are at an increased risk for growth and genomic imprinting disorders, often associated with DNA methylation defects. Folic acid supplementation is recommended during pregnancy to prevent adverse offspring outcomes; however, the effects of folic acid supplementation in ART remain unclear.

STUDY DESIGN, SIZE, DURATION

Outbred female mice were fed three folic acid-supplemented diets, control (rodent daily recommended intake or DRI; CD), moderate (4-fold DRI; 4FASD) or high (10-fold DRI; 10FASD) dose, for six weeks prior to ART and throughout gestation. Mouse ART involved a combination of superovulation, in vitro fertilisation, embryo culture and embryo transfer.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Midgestation embryos and placentas (n = 74-99/group) were collected; embryos were assessed for developmental delay and gross morphological abnormalities and embryos and placentas were examined for epigenetic defects. We assessed methylation at four imprinted genes (Snrpn, Kcnq1ot1, Peg1 and H19) in matched midgestation embryos and placentas (n = 31-32/group) using bisulfite pyrosequencing. In addition, we examined genome-wide DNA methylation patterns in placentas (n = 6 normal placentas per sex/group) and embryos (n = 6 normal female embryos/group; n = 3 delayed female embryos/group) using reduced representation bisulfite sequencing (RRBS).

MAIN RESULTS AND THE ROLE OF CHANCE

Moderate, but not high dose supplementation, was associated with a decrease in the proportion of developmentally delayed embryos. Although moderate dose folic acid supplementation reduced DNA methylation variance at certain imprinted genes in embryonic and placental tissues, high dose supplementation exacerbated the negative effects of ART at imprinted loci. Furthermore, folic acid supplements resolved female-biased aberrant imprinted gene methylation. Supplementation was more effective at correcting ART-induced genome-wide methylation defects in male versus female placentas; however, folic acid supplementation also led to additional methylation perturbations which were more pronounced in males.

LARGE-SCALE DATA

The RRBS data from this study have been submitted to the NCBI Gene Expression Omnibus under the accession number GSE123143.

LIMITATIONS REASONS FOR CAUTION

Although the combination of mouse ART utilised in this study consisted of techniques commonly used in human fertility clinics, there may be species differences. Therefore, human studies, designed to determine the optimal levels of folic acid supplementation for ART pregnancies, and taking into account foetal sex, are warranted.

WIDER IMPLICATIONS OF THE FINDINGS

Taken together, our findings support moderation in the dose of folic acid supplements taken during ART.

STUDY FUNDING/COMPETING INTEREST(S)

This work was funded by the Canadian Institutes of Health Research (FDN-148425). The authors declare no conflict of interest.

Association of antenatal vitamin B complex supplementation with neonatal vitamin B12 status: evidence from a cluster randomized controlled trial

PURPOSE

Evidence about the effect of maternal vitamin B₁₂ supplementation on offspring's vitamin B₁₂ status is limited. The present interventional study sought to evaluate the association of antenatal vitamin B complex supplementation with neonatal vitamin B₁₂ status.

METHODS

In an ongoing cluster randomized controlled trial conducted in three rural counties in northwest China, pregnant women < 20 weeks of gestation were randomized to three treatment groups: blank control, iron supplements, or vitamin B complex supplements. All women were administered folic acid supplements during the periconceptional period. In a sub-study, we collected cord blood samples of 331 participants from the control or vitamin B complex groups in the Xunyi county from January 2017 to December 2017. Plasma concentrations of folate, vitamin B₁₂, and homocysteine were measured. Linear mixed models with a random intercept for cluster were used to compare biochemical indexes between groups after controlling for covariates.

RESULTS

Compared with newborns whose mothers were in the control group, newborns of the vitamin B complex-supplemented women had significantly higher cord plasma vitamin B₁₂ (P = 0.001) and lower homocysteine concentrations (P = 0.043). The association of antenatal vitamin B complex supplementation with cord blood vitamin B₁₂ concentrations appeared to be more pronounced among newborns with high folate status than those with low folate status (P_interaction = 0.060).

CONCLUSIONS

Maternal vitamin B complex supplementation during pregnancy was associated with better neonatal vitamin B₁₂ status in rural northwest China.

Dietary Intake across Reproductive Life Stages of Women in India: A Cross-Sectional Survey from 4 Districts of India

Nutritional deficiencies among women of reproductive age, especially from socially backward classes, are widely prevalent in India. The present study aimed to assess the nutrient intakes and analyse their associations with sociodemographic attributes among socially backward adolescent girls, newly married women, pregnant women, and lactating mothers from four districts of India. Further, the study looked at the associations between nutrient intakes and anthropometric measurements (body mass index, BMI; waist circumference; and waist-hip ratio, WHR) among adolescents and newly married women. This community-based cross-sectional study used the 24-hour recall method of the dietary survey to assess the food intake of women and girls. Nonparametric tests of associations between sociodemographic characteristics and the median nutrient intakes were conducted. Expected and observed increments in energy and nutrient intakes of pregnant and lactating women from the base (requirement of an adult woman) were calculated. A total of 477 pregnant women, 455 lactating mothers, 532 newly married women, and 223 adolescent girls were interviewed. According to the 24-h dietary recall, only 35% of adolescent girls, 57% newly married women, 40% pregnant women, and 34% lactating mothers were able to meet 70% of the recommended energy requirements. A large percentage of pregnant women had less than 50% of the recommended intakes of iron, calcium, and folic acid. Women living in nuclear families, urban slums, and those from backward classes had lower intakes of almost all the nutrients compared to their counterparts (p < 0.001). There were no significant differences in the nutrient intakes of adolescents, newly married, pregnant, and lactating women, and all had poor dietary intakes. We found positive relationships of all three anthropometric measurements (BMI, waist circumference, and WHR) with fats and inverse associations with carbohydrates. Public health interventions should work towards improving the nutrition of these vulnerable populations.

Folic acid supplementation in Italian women during pregnancy: A cross-sectional study conducted in general practice

OBJECTIVES

The association between folate insufficiency and congenital neural tube defects has been extensively investigated since the 1990s. To reach an adequate intake of folic acid (FA), improving folate status through periconceptional supplementation with FA, promotion of the consumption of foods rich in natural folates, and appropriate use of fortified foods is recommended. The aim of the present study was to investigate the supplementation of FA in a sample of pregnant women referred to general practice services in Italy, with a focus on the quality of information received by fertile women.

METHODS

Participants were recruited from patients admitted to 44 general practice offices enrolled in the Italian Society of Preventive Medicine and Lifestyle study and located in Italy throughout the national territory. A questionnaire for the evaluation of FA supplementation was administered by the general practitioners (GPs). The interviewed subjects were asked to provide information about pregnancy characteristics, nutritional habits, lifestyle and risk factors, information sources, and knowledge about FA.

RESULTS

This study included 328 participants. The percentage of women who did not take any FA supplements was 16.8%, and 66.4% of women started FA supplementation only after finding out they were pregnant. Only 16.8% of women started FA supplementation 12 wk before the beginning of pregnancy. The lack of supplementation with FA, as well as the incorrect adherence to the existing FA supplementation protocol, is attributable to different social (e.g., immigration, place of residence, job employment) and cultural (e.g., educational level, knowledge about FA) factors, the relatively poor planning of pregnancies, and the lack of information concerning the need for FA supplementation in the prepregnancy period. Finally, GPs and gynecologists are the only sources of information on the importance of FA supplementation.

CONCLUSIONS

The adherence of women to FA supplementation before pregnancy is still insufficient. The GP role in preconception care, and the promotion of FA supplementation, needs to be emphasized and further promoted.

Distribution of 5-Methyltetrahydrofolate and Folic Acid Levels in Maternal and Cord Blood Serum: Longitudinal Evaluation of Japanese Pregnant Women

“Total” folate in blood has usually been measured to evaluate the folate status of pregnant women. However, folate is composed of many metabolites. The main substrate is 5-methyltetrahydrofolate (5-MTHF), with folic acid (FA) representing a very small component as an unmetabolized species in blood. We longitudinally evaluated 5-MTHF, FA and total homocysteine in maternal and cord blood from Japanese pregnant women. Subjects were 146 pregnant women who participated in the Chiba study of Mother and Child Health (C-MACH) prospective cohort study. Sera were obtained in early and late pregnancy, at delivery, and from cord blood. Species levels were measured by isotope-dilution mass spectrometry. Both 5-MTHF and FA levels were lower than reported levels from pregnant women in populations from countries with mandatory FA fortification. As gestational age progressed, serum 5-MTHF levels decreased, whereas serum FA levels were slightly reduced only at delivery compared to early pregnancy. A significant negative association between serum 5-MTHF and total homocysteine was shown at all examined times, but no associations with FA were evident. At delivery, cord 5-MTHF was significantly higher than maternal levels, while FA again showed no significant correlation. These results suggest that 5-MTHF is actively transported to the fetus through placental transporters and may reflect folate status during pregnancy as a physiologically important species.

Prenatal fruit juice exposure enhances memory consolidation in male post-weanling Sprague-Dawley rats

Objectives

Nutritional intake during gestation is known to impact health outcomes for progeny. Correlational evidence in humans suggests that increased fruit consumption of pregnant mothers enhances infant cognitive development. Moreover, wild-type Drosophila supplemented with a combination of orange and tomato juice showed robust enhancements in performance on an associative olfactory memory task. The current study aimed to experimentally test the effects of prenatal fruit juice exposure in a non-human, mammalian model of learning and memory.

Methods

Across three separate birth cohorts, pregnant rats were given access to diluted tomato and orange juice (N = 2 per cohort), with control rats (N = 2 per cohort) receiving only water, in addition to standard rodent chow, throughout the duration of gestation, ending at parturition. Following weaning, male offspring were tested for learning and memory in a spatial version of the circular water maze and an auditory-cued fear-conditioning task.

Results

All pregnant rats increased fluid and food intake over the gestational period. Fruit juice-fed pregnant rats had increased fluid intake compared to control pregnant rats. When testing progeny, there were no effects of prenatal fruit juice on spatial learning, while it appeared to impair learning in fear conditioning relative to controls. However, we measured significant enhancements in both spatial memory and conditioned fear memory in the prenatal fruit-juice group compared to controls. Measures of vigilance, in response to the conditioned cue, were increased in prenatal fruit rats compared to controls, suggesting less generalized, and more adaptive, anxiety behaviours.

Discussion

Our results corroborate the human and Drosophila findings of prenatal fruit effects on behaviour, specifically that prenatal fruit juice exposure may be beneficial for early-life memory consolidation in rats.

Impact of mothers' early life exposure to low or high folate on progeny outcome and DNA methylation patterns

The dynamic patterning of DNA and histone methylation during oocyte development presents a potentially susceptible time for epigenetic disruption due to early life environmental exposure of future mothers. We investigated whether maternal exposure to folic acid deficient and supplemented diets starting in utero could affect oocytes and cause adverse developmental and epigenetic effects in next generation progeny. Female BALB/c mice (F0) were placed on one of four amino acid defined diets for 4 weeks before pregnancy and throughout gestation and lactation: folic acid control (rodent recommended daily intake; Ctrl), 7-fold folic acid deficient, 10-fold folic acid supplemented or 20-fold folic acid supplemented diets. F1 female pups were weaned onto Ctrl diets, mated to produce the F2 generation and the F2 offspring were examined at E18.5 for developmental and epigenetic abnormalities. Resorption rates were increased and litter sizes decreased amongst F2 E18.5-day litters in the 20-fold folic acid supplemented group. Increases in abnormal embryo outcomes were observed in all three folic acid deficient and supplemented groups. Subtle genome-wide DNA methylation alterations were found in the placentas and brains of F2 offspring in the 7-fold folic acid deficient , 10-fold folic acid supplemented and 20-fold folic acid supplemented groups; in contrast, global and imprinted gene methylation were not affected. The findings show that early life female environmental exposures to both low and high folate prior to oocyte maturation can compromise oocyte quality, adversely affecting offspring of the next generation, in part by altering DNA methylation patterns.

Folic acid deficiency declined substantially after introduction of the mandatory fortification programme in Queensland, Australia: a secondary health data analysis

OBJECTIVE

To investigate the prevalence of folic acid deficiency in Queensland-wide data of routine laboratory measurements, especially in high-risk sub-populations.

DESIGN

Secondary health data analysis.

SETTING

Analysis of routine folic acid tests conducted by Pathology Queensland (AUSLAB).

PARTICIPANTS

Female and male persons aged 0-117 years with routine folic acid testing between 1 January 2004 and 31 December 2015. If repeat tests on the same person were conducted, only the initial test was analysed (n 291 908).

RESULTS

Overall the prevalence of folic acid deficiency declined from 7·5 % before (2004-2008) to 1·1 % after mandatory folic acid fortification (2010-2015; P < 0·001) reflecting a relative reduction of 85 %. Levels of erythrocyte folate increased significantly from a median (interquartile range) of 820 (580-1180) nmol/l in 2008 before fortification to 1020 (780-1350) nmol/l in 2010 (P < 0·001) after fortification. The prevalence of folic acid deficiency in the Indigenous population (14 792 samples) declined by 93 % (17·4 v. 1·3 %; P < 0·001); and by 84 % in non-Indigenous residents (7·0 v. 1·1 %; P < 0·001). In a logistic regression model the observed decrease of folic acid deficiency between 2008 and 2010 was found independent of gender, age and ethnicity (ORcrude = 0·20; 95 % CI 0·18, 0·23; P < 0·001; ORadjusted = 0·21; 95 % CI 0·18, 0·23; P < 0·001).

CONCLUSIONS

While voluntary folic acid fortification, introduced in 1995, failed especially in high-risk subgroups, the 2009 mandatory folic acid fortification programme coincided with a substantial decrease of folic acid deficiency in the entire population.

Optimization of folic acid supplementation in the prevention of neural tube defects

Background

We examined the relationship between timing and duration of folic acid (FA) supplementation in achieving red blood cell (RBC) folate levels in early pregnancy which are optimal (>906 nmol/l) for the prevention of neural tube defects (NTDs).

Methods

Clinical, FA supplementation and dietary folate details were computerized at the first antenatal visit. Maternal blood samples were analysed for RBC and serum folate.

Results

Of the 502 women, 98.2% (n = 493) reported taking FA. There was a positive correlation between duration of supplementation and both RBC folate (r = 0.43, P < 0.001) and serum folate (rho = 0.29, P < 0.001). The optimal RBC folate level was achieved in 80.4% (n = 46) of women who started FA 400 μg 4-8 weeks before their LMP compared with only 53.6% (n = 153) in women who started 4-8 weeks after their LMP (P < 0.001).

Conclusions

This study provides, for the first time, information on both the timing and duration of FA that will achieve the optimum RBC folate levels associated with the prevention of NTDs. Women who are taking FA (400 μg) need to start before they conceive.

The Associations between the Duration of Folic Acid Supplementation, Gestational Diabetes Mellitus, and Adverse Birth Outcomes based on a Birth Cohort

This study aimed to examine the associations between the duration of folic acid (FA) supplementation, gestational diabetes mellitus (GDM), and adverse birth outcomes. A total of 950 mother-offspring pairs participated in the cohort study during 2015 in Changsha, China. The data were collected through home visits and perfected by maternal and child healthcare handbooks. Generalized linear models and stratified analyses were used for statistical analyses. The incidence of GDM in our cohort was 10.2%. FA supplementation for ≥3 months before pregnancy was associated with an increased risk of GDM (adjusted relative risk (aRR): 1.72; 95% CI: 1.17–2.53) and decreased risk of small-for-gestational-age (SGA) birth (aRR: 0.40; 95% CI: 0.18–0.88). In the group of FA supplementation for ≥3 months during pregnancy, GDM was associated with an increased risk of cesarean delivery (aRR: 1.36; 95% CI: 1.06–1.75) and macrosomia (aRR: 2.11; 95% CI: 1.06, 4.20), but the aRRs were lower than the RR_MH 1.53 (95% CI: 1.01–2.34) and 2.43 (95% CI: 1.27–4.66). Our study suggested that the longer duration of FA supplementation before pregnancy might increase the risk of GDM, but decrease the risk of SGA birth. Longer duration of FA supplementation during pregnancy had beneficial effects on birth outcomes in women with GDM. Further studies should consider a larger sample size to confirm these findings.