Explore the vast range of titles available.

To summarize the recommendations on folate intake and folic acid supplementation and fortification in the periconceptional period, aimed at prevention of neural tube defects (NTD), provided by official health organizations in different countries worldwide and WHO. Information on recommendations for folate and folic acid intake in the periconceptional period was gathered from the websites of official national health organizations of several countries worldwide and from the WHO website. WHO, selected developed countries and emerging economies, totalling thirty-six countries worldwide (some European, BRICS, G8, Asian Tiger/Asian Dragon and Australia). Recommendations differ between countries, although the majority (69·4 %) recommend a healthy diet plus a folic acid supplement of 400 µg/d from preconception (4-12 weeks) until the end of the first trimester of pregnancy (8-12 weeks). The same recommendation is issued by the WHO. Dosages for women at high risk of NTD are up to 4-5 mg/d (for 41·7 % of studied countries). The recommended intake for folate is in the range of 300-400 µg/d for women of childbearing age and 500-600 µg/d for pregnant women in different countries and WHO. Five countries emphasize the importance of a healthy diet rendering supplementation needless. By contrast, five others advise a healthy diet and supplementation plus mandatory fortification. Only one mentions the importance of ensuring an adequate folate status and refers to checking with a health-care provider on the need for supplements. Different recommendations regarding folate and folic acid, seeking NTD prevention, are available worldwide; however, most countries and WHO focus on a healthy diet and folic acid supplementation of 400 µg/d periconceptionally.

The results from epidemiologic studies linking blood folate concentrations, folic acid supplementation, or dietary folate to the risk of preterm birth are inconsistent. In this study, we aimed to summarize the available evidence on these associations. A systematic search of the PubMed/MEDLINE, Google Scholar, Web of Science, and Cochrane Library databases up to October 20, 2018 was performed and reference lists of retrieved articles were screened. Pooled odds ratios (ORs) and 95% confidence intervals (CIs) for the highest vs. the lowest levels of folate concentrations, folic acid supplementation, and dietary folate were calculated using random-effects models. Subgroup analyses and univariate meta-regression were performed to explore the sources of heterogeneity. Ten studies (six prospective cohort studies and four case-control studies) were included on folate concentrations, 13 cohort studies were included about folic acid supplementation, and 4 cohort studies were included regarding dietary folate intake. Higher maternal folate levels were associated with a 28% reduction in the risk of preterm birth (OR 0.72, 95% CI 0.56-0.93). Higher folic acid supplementation was associated with 10% lower risk of preterm birth (OR 0.90, 95% CI 0.85-0.95). In addition, a significant negative association was observed between dietary folate intake and the risk of preterm birth (OR 0.68, 95% CI 0.55-0.84), but no significant relation was seen between dietary folate and the risk of spontaneous preterm birth (OR 0.89, 95% CI 0.57-1.41). In the subgroup analysis, higher maternal folate levels in the third trimester were associated with a lower risk of preterm birth (OR 0.58, 95% CI 0.36-0.94). To initiate taking folic acid supplementation early before conception was adversely associated with preterm birth risk (OR 0.89, 95% CI 0.83-0.95). In conclusion, higher maternal folate levels and folic acid supplementation were significantly associated with a lower risk of preterm birth. The limited data currently available suggest that dietary folate is associated with a significantly decreased risk of preterm birth.

BackgroundLow birthweight (LBW) as well as early childhood stunting are risk factors for increased childhood morbidity in low-and middle-income countries (LMIC). The Covid 19 pandemic has exacerbated food insecurity and unemployment globally, prompting concerns for maternal and child health.ObjectivesWe used data from the great recession of 2008 to examine the relationship between household food security and other risk factors with LBW and stunting using a longitudinal sample of South African women and their offspring.MethodsFood security indicators, alcohol use, blood pressure and other characteristics were examined in relation to LBW (≤ 2500 g), stunting (height for age ≤ 2SD) and severe stunting (height for age ≤ 3SD). Regression modelling with clustering at maternal ID level were employed to adjust for maternal characteristics and women who gave birth more than once during the reference period.ResultsBirthweight data were available for 1173 children and height for age 1216 children. The prevalence of LBW was 14.7% while stunting and severe stunting was 17.8% and 14.5%. Child hunger in the household, maternal hypertension and alcohol use were associated with low birthweight. Food expenditure below the Stats SA poverty line and low dietary diversity was associated with stunting and severe stunting respectively. Maternal height and low birthweight were associated with both stunting and severe stunting.Conclusions for PracticeInterventions that can improve household food security and nutritional status during the periconceptional and antenatal period may reduce the prevalence of low birthweight and subsequent stunting in low- and middle-income countries.

A complex combination of adult health-related disorders can originate from developmental events that occur in utero. The periconceptional period may also be programmable. We report on the effects of restricting the supply of specific B vitamins (i.e., B₁₂ and folate) and methionine, within normal physiological ranges, from the periconceptional diet of mature female sheep. We hypothesized this would lead to epigenetic modifications to DNA methylation in the preovulatory oocyte and/or preimplantation embryo, with long-term health implications for offspring. DNA methylation is a key epigenetic contributor to maintenance of gene silencing that relies on a dietary supply of methyl groups. We observed no effects on pregnancy establishment or birth weight, but this modest early dietary intervention led to adult offspring that were both heavier and fatter, elicited altered immune responses to antigenic challenge, were insulin-resistant, and had elevated blood pressure-effects that were most obvious in males. The altered methylation status of 4% of 1,400 CpG islands examined by restriction landmark genome scanning in the fetal liver revealed compelling evidence of a widespread epigenetic mechanism associated with this nutritionally programmed effect. Intriguingly, more than half of the affected loci were specific to males. The data provide the first evidence that clinically relevant reductions in specific dietary inputs to the methionine/folate cycles during the periconceptional period can lead to widespread epigenetic alterations to DNA methylation in offspring, and modify adult health-related phenotypes.

Objectives: To summarize the best evidence regarding folic acid supplementation for preventing neural tube defects (NTDs) in women of childbearing age and to develop a structured evidence summary for guiding clinical practice. Methods: We systematically searched multiple databases and professional websites from 1 January 2013 to 18 September 2025. Sources included 7 databases and 20 professional websites. The search targeted clinical guidelines, expert consensuses, best practices, and recommended practices on folic acid supplementation for NTD prevention in women of childbearing age. The retrieved literature underwent quality assessment, evidence extraction, and summarization. Results: The review included 17 publications: 10 guidelines, 4 expert consensuses, 2 recommended practices, and 1 best practice. From these, 14 distinct evidence statements were synthesized and organized into five thematic dimensions: risks of neural tube defects and the role of folic acid, time window of neural tube closure, timing and dosage of folic acid supplementation, relationship between dietary folic acid and folic acid tablets, and folic acid-related testing. The key recommendations include initiating supplementation at least 3 months preconception, with daily doses of 0.4 mg for low-risk, 1.0 mg for moderate-risk, and 4.0–5.0 mg for high-risk women, continuing through the first trimester, emphasizing that dietary intake alone is insufficient, and advising against routine folate testing. Conclusions: This study synthesized the best available evidence regarding folic acid supplementation for preventing NTDs in women of childbearing age, providing an evidence-based foundation to inform clinical practice, particularly for healthcare systems and populations in regions without mandatory folic acid food fortification.

To assess the vitamin D nutritional status (VDN) of pregnant women in early pregnancy and investigate the effects of periconceptional supplementation with multiple micronutrients (MMs) on this status. Data were taken from the Pregnancy Health Care System and Hospital Information System in 2018 in Beijing. Vitamin D nutritional status in early pregnancy was evaluated among 4,978 pregnant women, and 4,540 women who took folic acid only (FA) or multiple mi-cronutrients supplements (MM) during the periconceptional period, were include to estimate the associations between periconceptional supplementation with MM and prevalence of vitamin D deficiency or insufficiency with logistic regression model. The mean early-pregnancy vitamin D concentration was 18.6 (±7.5) ng/mL, and the rates of deficiency and insufficiency were 31.6% and 60.5%, respectively. Compared to the FA group, the adjusted odds ratio (aOR, 95%confidence interval, CI) for insufficiency or deficiency of the MM group were 0.25(0.18-0.34), and the aOR (95%CI) for deficiency of the MM group were 0.17 (0.12-0.23). Women who took MMs for a longer period of time, at higher frequencies, and with higher compliance scores had lower rates of deficiency and insufficiency. In winter, spring, and autumn, taking MMs could reduce deficiency by about 70%; in summer, there was little effect. Among women in Beijing, serum concentrations of vitamin D in early pregnancy are relatively low, and the rates of deficiency and insufficiency are high. Taking MMs during the periconceptional period could improve this situation.

Abstract Periconceptional maternal obesity is linked to adverse maternal and neonatal outcomes. Identifying periconceptional biomarkers of pathways affected by maternal obesity can unravel pathophysiologic mechanisms and identify individuals at risk of adverse clinical outcomes. The literature was systematically reviewed to identify periconceptional biomarkers of the endocrine, inflammatory and one-carbon metabolic pathways influenced by maternal obesity. A search was conducted in Embase, Ovid Medline All, Web of Science Core Collection and Cochrane Central Register of Controlled Trials databases, complemented by manual search in PubMed until December 31st, 2020. Eligible studies were those that measured biomarker(s) in relation to maternal obesity, overweight/obesity or body mass index (BMI) during the periconceptional period (14 weeks preconception until 14 weeks post conception). The ErasmusAGE score was used to assess the quality of included studies. Fifty-one articles were included that evaluated over 40 biomarkers. Endocrine biomarkers associated with maternal obesity included leptin, insulin, thyroid stimulating hormone, adiponectin, progesterone, free T4 and human chorionic gonadotropin. C-reactive protein was associated with obesity as part of the inflammatory pathway, while the associated one-carbon metabolism biomarkers were folate and vitamin B12. BMI was positively associated with leptin, C-reactive protein and insulin resistance, and negatively associated with Free T4, progesterone and human chorionic gonadotropin. Concerning the remaining studied biomarkers, strong conclusions could not be established due to limited or contradictory data. Future research should focus on determining the predictive value of the optimal set of biomarkers for their use in clinical settings. The most promising biomarkers include leptin, adiponectin, human chorionic gonadotropin, insulin, progesterone and CRP.

Background Periconceptional folic acid supplementation (FAS) is known to reduce the risk of adverse pregnancy outcomes, but limited evidence exists on its national coverage and socioeconomic disparities in China. Methods This study used data from a nationwide survey of over 11 million reproductive-aged couples between 2012 and 2019 to examine patterns, trends, and inequalities in overall and adequate FAS use. Modified Poisson regression models were used to estimate the associations between parental separate and joint SES indicators and periconceptional FAS use. Socioeconomic inequalities were quantified using the Erreygers Concentration Index based on maternal education. Results Overall FAS use increased from 2012 to 2019 to reach 92.6% (95% CI 89.8%–95.5%) in urban and 92.1% (95% CI 90.4%–93.8%) in rural areas. Despite this increase, adequate adherence remained suboptimal at 64.8% (95% CI 59.9%–69.6%) for urban and 66.0% (95% CI 61.2%–70.8%) for rural participants. Lower maternal SES was strongly associated with reduced FAS use. Decomposition analysis established maternal education as the primary driver of inequality and accounted for the largest disparity in adequate use. Although maternal factors mediated the influence of paternal education on overall use, low paternal education persisted as an independent barrier to adequate adherence. Conclusions Our study confirms a relatively low rate of adequate periconceptional FAS use. Prevention efforts should target high-risk groups by addressing specific risk factors and broader determinants of health.

The required intake of macronutrients by women during the periconceptional period for optimal fetal growth is the subject of ongoing investigation. Intake of polyunsaturated fatty acids (PUFA) is positively associated with fetal neural development, growth velocity and birth weight. However, limited evidence indicates that PUFAs play a role in embryogenesis. We aim to investigate the associations between maternal PUFA dietary intake and first trimester embryonic volume (EV) and head volume (HV). In a prospective cohort study (2013–2020), 464 pregnant women at < 8 weeks of gestation were included. Maternal dietary intake of PUFAs, including omega 3 (docosahexaenoic acid, DHA and eicosapentaeonic acid, EPA) and 6, was obtained from food frequency questionnaires, and first trimester three-dimensional ultrasound examinations were performed to measure EV and HV using Virtual Reality techniques. More than 70% of the population had omega 3 intakes below recommendations. A higher intake of PUFAs was associated with a smaller embryonic HV/EV ratio after adjusting for confounders (EPA p  = 0.012, DHA p  = 0.015, omega 3 and 6 p  < 0.001), but no associations were found with EV or HV alone. Omega 3 from fish oil supplements alone was not associated with embryonic growth. Strong adherence to a PUFA-rich dietary pattern was associated with a smaller embryonic HV/EV ratio (DHA and EPA-rich diet p  = 0.054, PUFA-rich diet p  = 0.002). It is important to increase awareness of the high prevalence of omega 3-deficiency among pregnant women, and the opportunity for prevention by increasing PUFA intake, thereby reducing the risks of adverse pregnancy outcomes which originate during the periconceptional period.