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

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

Prevalence and Trends of Birth Defects - Five Counties, Shanxi Province, China, 2003-2022.

What is already known about this topic?: The Shanxi Province, located in northern China, holds the highest prevalence of birth defects (BDs) across the country. Following the implementation of a nationwide folic acid supplementation program in 2009, a significant reduction of 53.89% in the prevalence of neural tube defects (NTDs) was observed in Shanxi from 2012 to 2017. However, despite this decrease, the prevalence rate for congenital heart defects (CHDs) in 2017 was over four times that of the 2012 rate. Since 2014, CHDs have emerged as the most predominant BD in Shanxi. What is added by this report?: The present study has identified a marked reduction in the prevalence of both total BDs and NTDs in five counties within Shanxi over the past two decades. As of 2017-2022, NTDs continue to be the most prevalent BDs recorded in this region. Contrarily, there has been a noteworthy increase in the prevalence of CHDs, ranking them among the top five most common BDs in the region between 2017 and 2022, though their rate remains below the national average. Additionally, the proportion of external anomalies remains high. Nevertheless, due to constrained access to primary healthcare services and diagnostic facilities, the early detection rate for internal anomalies, particularly CHDs, may be underestimated in the region. What are the implications for public health practice?: The results of this study underscore the necessity for augmented efforts in promoting folic acid supplementation as a preventive measure for NTDs. Moreover, improvements in the distribution of medical resources within this region are recommended, particularly the introduction and enforcement of local training programs aimed at enhancing CHD screening and diagnostic processes in these respective counties.

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

What is already known about this topic?: Robust evidence indicates that supplementing with folic acid periconceptionally may decrease the risk of neural tube defects (NTDs) in fetuses. What is added by this report?: Over half of the mothers in both the NTD case group and the control group utilized folic acid supplements during the periconceptional period, showing no notable variations between the two groups. However, there was a significantly higher percentage of mothers with NTD cases who exhibited poor compliance in folic acid use compared to control mothers. A significantly lowered compliance with folic acid intake was observed among women facing unintended pregnancies and those with lower education levels. What are the implications for public health practice?: Universal education regarding folic acid action for women of childbearing age should be strengthened to improve compliance with folic acid supplementation in the periconceptional period and further reduce the prevalence of NTDs.

Periconceptional Folic Acid Only Versus Multiple Micronutrients Containing Folic Acid and Association with Gestational Diabetes Mellitus - Beijing Municipality, China, 2017-2021.

What is already known about this topic?: Inconsistent results have been reported on the association between periconceptional folic acid only (FAO) or multiple micronutrients containing folic acid (MMFA) supplementation and the risk of gestational diabetes mellitus (GDM) in previous research. What is added by this report?: In a prospective cohort study conducted among pregnant women in Haidian District, Beijing Municipality, it was observed that those who took MMFA demonstrated a higher likelihood of developing GDM in comparison to those who consumed FAO periconceptionally. Interestingly, the increased risk for GDM in pregnant women supplemented with MMFA compared to FAO was primarily due to changes in fasting plasma glucose. What are the implications for public health practice?: It is highly recommended that women prioritize the use of FAO in order to yield potential benefits in the prevention of GDM.

Folic acid supplements and perinatal mortality in China.

Introduction: Periconceptional use of multivitamins containing folic acid prevents external major birth defects, especially neural tube defects. We aimed to explore the effects of maternal folic acid supplementation alone on perinatal mortality with or without external major birth defects plus neural tube defects. Methods: From the China-US Collaborative Project for Neural Tube Defects Prevention, we identified 222, 303 singleton pregnancies with detailed information on periconceptional folic acid use, defined as folic acid supplementary before the last menstrual date until to the end of the first trimester. Perinatal mortality included stillbirths after 20 weeks' gestation and early neonatal deaths within 7 days of delivery. Results: Among the fetuses or infants of women who did not take folic acid, the rate of perinatal mortality was 2.99% and 1.62% at least 20 weeks' gestation in the northern and southern regions. Among the fetuses or infants of the women with periconceptional use of folic acid, the rates were 1.85% and 1.39% in the northern and southern region. The estimated relative risk for perinatal mortality [adjusted risk ratio (RR), 0.72; 95% confidence interval (CI), 0.61- 0.85], stillbirth (adjusted RR, 0.78; 95% CI, 0.64-0.96), early neonatal mortality (adjusted RR, 0.61; 95% CI, 0.45-0.82), and neonatal death (adjusted RR, 0.64; 95% CI, 0.49-0.83) in northern China was significantly decreased in association with periconceptional folic acid supplementation. Compared with northern, there was a lesser effect in southern China. Conclusion: Periconceptional intake of 400µg folic acid daily reduces the overall risk perinatal mortality, as well as the risk from external major birth defects and neural tube defects, especially in northern China.

Community structure of endophytic fungi in roots and leaves of Fagopyrum mill and Avena sativa in a Chinese northern cold region

In order to explore the endophytic fungi of Fagopyrum Mill and Avena sativa, Illumina Miseq high-throughput sequencing was used to analyze the community structure and diversity of endophytic fungi in leaves and roots of buckwheat and oat at the mature stage. The results of community structure showed that there were 205 operational taxonomic units (OTUs) in buckwheat roots and 181 OTUs in buckwheat leaves based on 97% sequence similarity level. There were 152 OTUs and 127 OTUs in the root and the leaf of oat, respectively. At the phylum level, Ascomycota and Basidiomycota were the dominant endophytic fungi in buckwheat roots and leaves, while Ascomycota was the dominant endophytic fungus in oat roots and leaves. Alpha diversity analysis showed that the Ace index, Chao index and Shannon index of buckwheat roots were higher than that of buckwheat leaves, and the three indices of oat roots were also higher than that of oat leaves, indicating that the richness and diversity of endophytic fungi community in roots were higher than that in leaves. Biomarkers were found by significant difference analysis in buckwheat and oat. The endophytic functional groups of buckwheat and oat were mainly distributed in Pathotroph and Saprotroph. The results of this study laid a foundation for fully exploiting the dominant endophytic fungal resources of buckwheat and oat and further developing microbial fertilizers.

Metal-dependent programmed cell death-related lncRNA prognostic signatures and natural drug sensitivity prediction for gastric cancer.

Background: Gastric cancer is one of the most important malignancies with poor prognosis. Ferroptosis and cuproptosis are newly discovered metal-dependent types of programmed cell death, which may directly affect the outcome of gastric cancer. Long noncoding RNAs (lncRNAs) can affect the prognosis of cancer with stable structures, which could be potential prognostic prediction factors for gastric cancer. Methods: Differentially expressed metal-dependent programmed cell death (PCD)-related lncRNAs were identified with DESeq2 and Pearson's correlation analysis. Through GO and KEGG analyses and GSEA , we identified the potential effects of metal-dependent PCD-related lncRNAs on prognosis. Using Cox regression analysis with the LASSO method, we constructed a 12-lncRNA prognostic signature model. Also, we evaluated the prognostic efficiency with Kaplan-Meier (K-M) survival curve, receiver operating characteristic (ROC) curve, and decision curve analysis (DCA) methods. The sensitivities for antitumor drugs were then predicted with the pRRophetic method. Also, we discuss Chinese patent medicines and plant extracts that could induce metal-dependent programmed cell death. Results: We constructed a metal-dependent PCD-related lncRNA-gene co-expression network. Also, a metal-dependent PCD-related gastric cancer prognostic signature model including 12 lncRNAs was constructed. The K-M survival curve revealed a poor prognosis in the high-risk group. ROC curve analysis shows that the AUC of our model is 0.766, which is better than that of other published models. Moreover, the half-maximum inhibitory concentration (IC50) for dasatinib, lapatinib, sunitinib, cytarabine, saracatinib, and vinorelbine was much lower among the high-risk group. Conclusion: Our 12 metal-dependent PCD-related lncRNA prognostic signature model may improve the OS prediction for gastric cancer. The antitumor drug sensitivity analysis results may also be helpful for individualized chemotherapy regimen design.

Non-Isolated Neural Tube Defects with Comorbid Malformations Are Responsive to Population-Level Folic Acid Supplementation in Northern China.

OBJECTIVE: Comorbid congenital malformation of multiple organs may indicate a shared genetic/teratogenic causality. Folic acid supplementation reduces the population-level prevalence of isolated neural tube defects (NTDs), but whether complex cases involving independent malformations are also responsive is unknown. We aimed to describe the epidemiology of NTDs with comorbid malformations in a Chinese population and assess the impact of folic acid supplementation. STUDY DESIGN: Data from five counties in Northern China were obtained between 2002 and 2021 through a population-based birth defects surveillance system. All live births, stillbirths, and terminations because of NTDs at any gestational age were recorded. NTDs were classified as spina bifida, anencephaly, or encephalocele. Isolated NTDs included spina bifida cases with presumed secondary malformations (hydrocephalus, hip dislocation, talipes). Non-isolated NTDs were those with independent concomitant malformations. RESULTS: A total of 296,306 births and 2031 cases of NTDs were recorded from 2002-2021. A total of 4.8% of NTDs (97/2031) had comorbid defects, which primarily affected the abdominal wall (25/97), musculoskeletal system (24/97), central nervous system (22/97), and face (15/97). The relative risk of cleft lip and/or palate, limb reduction defects, hip dislocation, gastroschisis, omphalocele, hydrocephalus, and urogenital system defects was significantly greater in infants with NTDs than in the general population. Population-level folic acid supplementation significantly reduced the prevalence of both isolated and non-isolated NTDs. CONCLUSION: Epidemiologically, non-isolated NTDs follow similar trends as isolated cases and are responsive to primary prevention by folic acid supplementation. Various clinically-important congenital malformations are over-represented in individuals with NTDs, suggesting a common etiology.

Clinical exome sequencing of 1000 families with complex immune phenotypes: Toward comprehensive genomic evaluations.

BACKGROUND: Prospective genetic evaluation of patients at this referral research hospital presents clinical research challenges. OBJECTIVES: This study sought not only a single-gene explanation for participants' immune-related presentations, but viewed each participant holistically, with the potential to have multiple genetic contributions to their immune phenotype and other heritable comorbidities relevant to their presentation and health. METHODS: This study developed a program integrating exome sequencing, chromosomal microarray, phenotyping, results return with genetic counseling, and reanalysis in 1505 individuals from 1000 families with suspected or known inborn errors of immunity. RESULTS: Probands were 50.8% female, 71.5% were ≥18 years, and had diverse immune presentations. Overall, 327 of 1000 probands (32.7%) received 361 molecular diagnoses. These included 17 probands with diagnostic copy number variants, 32 probands with secondary findings, and 31 probands with multiple molecular diagnoses. Reanalysis added 22 molecular diagnoses, predominantly due to new disease-gene associations (9 of 22, 40.9%). One-quarter of the molecular diagnoses (92 of 361) did not involve immune-associated genes. Molecular diagnosis was correlated with younger age, male sex, and a higher number of organ systems involved. This program also facilitated the discovery of new gene-disease associations such as SASH3-related immunodeficiency. A review of treatment options and ClinGen actionability curations suggest that at least 251 of 361 of these molecular diagnoses (69.5%) could translate into ≥1 management option. CONCLUSIONS: This program contributes to our understanding of the diagnostic and clinical utility whole exome analysis on a large scale.

Cesarean delivery on maternal request and common child health outcomes: A prospective cohort study in China.

Background: Cesarean delivery vs vaginal delivery was reported to increase the risks of childhood obesity, pneumonia, anemia, and neurobehavioral disorders, but few studies were able to deal with the confounding biases associated with medical conditions indicating cesareans. This prospective cohort study aims to investigate the associations of non-medically indicated cesarean delivery on maternal request (CDMR) with these child health outcomes. Methods: Among 17 748 liveborn infants whose mothers (primiparas) participated in a randomized controlled trial on micronutrient supplementation and pregnancy outcomes during 2006-2009 in 5 rural counties in Hebei Province, China, 6972 singletons born by full-term spontaneous vaginal delivery (SVD) and 3626 by CDMR were extracted for the assessments of obesity (weight-for-height z-score >3) and pneumonia (self-reported) at 1.5-5 years in 2011. Some children were further randomly selected from these two groups for the assessments of anemia (hemoglobin <110 g/L, 2341 SVD and 2417 CDMR) and neurobehavioral disorders (raw score of Child Behavior Checklist larger than the 90th percentile of the normative sample, 1257 SVD and 1060 CDMR). Results: Compared with SVD, CDMR was associated with increased risks of obesity (adjusted odds ratio (aOR) = 1.41, 95% confidence interval (CI) = 1.14-1.75, P = 0.002) and anemia (aOR = 1.65, 95% CI = 1.28-2.12, P < 0.001), but not with the risk of pneumonia (aOR = 1.16, 95% CI = 0.94-1.45, P = 0.17) or neurobehavioral disorders (aORs varied from 0.82 to 0.91, P > 0.05) in childhood. Conclusions: Cesarean delivery, independent of cesarean indications, is likely associated with childhood obesity and anemia, indicating a need to keep pregnant women informed, especially those seeking CDMR, a need to explore possible improvement on obstetric service, and even a need for main stakeholders to reach a compromise in making a cesarean decision. Trial registration: ClinicalTrials.gov: NCT00133744 and NCT01404416.

Selenium protects against the likelihood of fetal neural tube defects partly via the arginine metabolic pathway.

BACKGROUND AND AIMS: Neural tube defects (NTDs) are severe congenital malformations and have a complex etiology. This study aimed to explore the association between selected essential trace elements (ETEs) and metabolic pathway markers in the serum of women and the likelihood of NTDs. METHODS: The study included 99 mothers of offspring with and 114 mothers of offspring without NTDs. Five ETEs (iron, zinc, selenium [Se], cobalt, and molybdenum) and 106 metabolic pathway markers in maternal serum were quantified. The associations between ETEs and metabolic pathway markers and the chance of NTDs were examined. Mediating effects of the metabolic pathway markers on the association between Se and the likelihood of NTDs were evaluated. RESULTS: Compared to a Se concentration below the median, a concentration above the median was associated with a decreased chance of NTDs with an odds ratio of 0.29 (95% confidence interval: 0.11-0.66). The concentrations of 32 metabolic pathway markers differed between mothers of offspring with and without NTDs; five of these (asymmetric dimethylarginine, ornithine, glutamate, proline, and phenylalanine) were associated with increased chances of NTDs, with adjusted odds ratios of 3.01 (1.31-7.31), 2.79 (1.18-6.86), 2.38 (1.03-5.75), 2.41 (1.05-5.75), and 2.27 (1.09-5.40), respectively, for the higher interquartile of concentration compared to the lower one. Three arginine pathway metabolic markers (i.e., dimethylarginine, ornithine, and proline) mediated the association between Se and the occurrence of NTDs. CONCLUSION: This study suggests an association between Se and a reduced chance of NTDs. The arginine pathway may play a role in mediating this association.

Prenatal uranium exposure and risk for fetal neural tube defects: A case-control study in women living in a rural area of northern China.

The adverse effects of uranium exposure on human health are well-known; less is known, however, regarding its association with congenital malformations. We conducted a case-control study to examine the association between prenatal exposure to uranium and risk for fetal neural tube defects (NTDs) using the concentration of uranium in placental tissue as an exposure marker in 408 NTD cases and 593 healthy controls. Uranium concentration was quantified with an inductively coupled plasma mass spectrometer. The odds ratios of NTDs for uranium exposure levels, categorized into quartiles, were estimated using logistic regression. The median concentration of uranium in the NTD group (0.409 ng/g) was significantly higher than that in the control group (0.218 ng/g). The risk for NTDs increased 2.52-fold (95% CI, 1.85-3.45) for concentrations of uranium above the median value for all participants. After adjusting for confounders, the risk for NTDs increased 1.36-fold (95% CI, 1.25-6.17), 1.77-fold (95% CI, 1.09-2.85), and 3.60-fold (95% CI, 2.30-5.64) for the second, third, and fourth quartiles of uranium concentrations compared to the lowest quartile, respectively. Prenatal exposure to uranium is a risk factor for NTDs in this population. Prospective studies are needed to further validate this finding.

Orofacial Clefts in High Prevalence Area of Birth Defects - Five Counties, Shanxi Province, China, 2000-2020.

WHAT IS ALREADY KNOWN ON THIS TOPIC?: The prevalence of structural birth defects, especially neural tube defects, decreased after national folic acid (FA) supplementation initiation. WHAT IS ADDED BY THIS REPORT?: The prevalence of orofacial clefts (OFCs) in five counties of Shanxi Province in northern China, including most subtypes except cleft palate, showed a downward trend in the past two decades. In this study, pre-perinatal prevalence increased due to earlier detection. WHAT ARE THE IMPLICATIONS FOR PUBLIC HEALTH PRACTICE?: Periconceptional supplementation with FA may contribute to the decline in OFCs prevalence, while the effect on the OFCs subtype needs further investigation. Continuing to advocate for earlier supplementation (3 months before conception) and increased supplementation frequency (daily consumption) could promote further reduction in the prevalence of OFCs. Specific surveillance of this effect in the era of universal three-child policy is warranted.

Rate of Correct Use of Folic Acid Supplementation Among Pregnant Women - Beijing Municipality, China, 2017-2019.

WHAT IS ALREADY KNOWN ON THIS TOPIC?: Neural tube defects can be effectively prevented by folic acid supplementation. However, compliance with the recommendations for supplementation is still low in China. WHAT IS ADDED BY THIS REPORT?: This study investigated the rate of correct use of folic acid supplementation and its risk factors among pregnant women in Beijing. Women who took folic acid correctly only comprised less than 50% of the total, possibly due to unexpected pregnancy. WHAT ARE THE IMPLICATIONS FOR PUBLIC HEALTH PRACTICE?: Given the low rate in Beijing, an area with high health literacy, the rate may also be low in other areas in China. Regulations for mandatory fortification of food with folic acid are recommended in China.

Associations between prenatal exposure to cadmium and lead with neural tube defect risks are modified by single-nucleotide polymorphisms of fetal MTHFR and SOD2: a case-control study.

BACKGROUND: Prenatal exposure to heavy metals is implicated in the etiology of birth defects. We investigated whether concentrations of cadmium (Cd) and lead (Pb) in umbilical cord tissue are associated with risk for neural tube defects (NTDs) and whether selected genetic variants of the fetus modify their associations. METHODS: This study included 166 cases of NTD fetuses/newborns and 166 newborns without congenital malformations. Umbilical cord tissue was collected at birth or elective pregnancy termination. Cd and Pb concentrations were assessed by inductively coupled plasma-mass spectrometry, and 20 single-nucleotide polymorphisms (SNPs) in 9 genes were genotyped. Odds ratios (ORs) with 95% confidence intervals (CIs) were used to estimate the risk for NTDs in association with metal concentrations or genotype using logistic regression. Multiplicative-scale interactions between the metals and genotypes on NTD risk were assessed with logistic regression, and additive-scale interactions were estimated with a non-linear mixed effects model. RESULTS: Higher concentrations of Cd were observed in the NTD group than in the control group, but no difference was found for Pb. Concentrations of Cd above the median level showed a risk effect, while the association between Pb and NTD risk was not significant in univariate analyses. The association of Cd was attenuated after adjusting for periconceptional folic acid supplementation. Fetuses with the AG and GG genotypes of rs4880 in SOD2 (superoxide dismutase 2) tended to have a lower risk, but fetuses with the CT and TT genotypes of rs1801133 in MTHFR (5,10-methylenetetrahydrofolatereductase) have a higher risk for NTDs when compared to their respective wild-type. rs4880 and Cd exhibited a multiplicative-scale interaction on NTD risk: the association between higher Cd and the risk for NTDs was increased by over fourfold in fetuses carrying the G allele [OR 4.43 (1.30-15.07)] compared to fetuses with the wild-type genotype. rs1801133 and Cd exposure showed an additive interaction, with a significant relative excess risk of interaction [RERI 0.64 (0.02-1.25)]. CONCLUSIONS: Prenatal exposure to Cd may be a risk factor for NTDs, and the risk effect may be enhanced in fetuses who carry the G allele of rs4880 in SOD2 and T allele of rs1801133 in MTHFR.

Effects of prenatal micronutrients supplementation timing on pregnancy-induced hypertension: Secondary analysis of a double-blind randomized controlled trial.

In this secondary analysis of data from a double-blind randomized controlled trial (clinicaltrials.gov identifier: NCT00133744) of micronutrient supplementation (multiple micronutrients [MMN], iron-folic acid [IFA] and folic acid [FA] alone), we examined the potential modifying effect of gestational age at enrolment on the association of antenatal supplementation and pregnancy-induced hypertension (PIH). We included 18,775 nulliparous pregnant women with mild or no anaemia who were enrolled at 20 weeks of gestation or earlier from five counties of northern China. Women were randomly assigned to receive daily FA, IFA or MMN from enrolment until delivery. We used logistic regression to evaluate the association between PIH and timing of micronutrient supplementation. The incidence of PIH was statistically significantly lower among women who began MMN supplementation before 12 gestational weeks compared with women who began MMN supplementation at 12 weeks or later (RR = 0.74, 95% CI: 0.60-0.91). A similar protective effect was observed for both early-onset (<28 weeks, RR 0.45, 0.21-0.96) and late-onset of PIH (≥28 weeks, RR 0.77, 0.63-0.96). No statistically significant association was observed between PIH occurrence and timing of supplementation for FA or IFA. Maternal MMN supplementation and antenatal enrolment during the first trimester of pregnancy appeared to be of importance in preventing both early- and late-onset of PIH.

Folic acid supplementation and risk for fetal abdominal wall defects in China: results from a large population-based intervention cohort study.

Folic acid (FA) can reduce the risk for selected birth defects other than neural tube defects. We examined whether FA has preventive effects against fetal abdominal wall defects (AWD) in a unique intervention cohort in China. Birth outcomes of 247 831 singleton births from a population-based cohort study with detailed pre-conceptional FA intake information were collected in China in 1993-1996. Information on births at 20 complete gestational weeks, including live births, stillbirths and pregnancy terminations, and all structural birth defects regardless of gestational week were recorded. The birth prevalence of omphalocele, gastroschisis and total fetal AWD was classified by maternal FA supplementation. The prevalence of total AWD was 4·30 per 10 000 births among women who took FA compared with 13·46 per 10 000 births among those who did not take FA in northern China and 6·28 and 5·18 per 10 000 births, respectively, in southern China. The prevalence of omphalocele was 0·54 per 10 000 births among women who took FA compared with 3·74 per 10 000 births among those who did not take FA in northern China and 1·79 and 1·44 per 10 000 births, respectively, in southern China. FA supplementation significantly prevented total AWD in multivariate analysis (relative risk 0·26, 95 % CI 0·11, 0·61) in northern China, although no preventive effect of FA on AWD was observed in southern China. FA supplementation successfully reduced the prevalence of AWD in northern China.

Folic acid supplementation and risk for congenital hydrocephalus in China.

OBJECTIVE: We examined whether folic acid (FA) supplementation prevented congenital hydrocephalus (CH) in more than 200 000 births in China. DESIGN: A large population-based cohort study. SETTING: All births at 20 complete gestational weeks, including live births, stillbirths and pregnancy terminations, and all structural birth defects regardless of gestational week were recorded. The prevalence of births with CH was classified by maternal characteristics and FA supplementation. CH was diagnosed in accordance with code 742.3 of the International Classification of Diseases, Ninth Revision, Clinical Modification, while non-neural tube defect (NTD) CH refers to CH without anencephaly (740), spina bifida (741) or encephalocele (742·0). PARTICIPANTS: A total of 247 831 pregnant women who delivered with known outcomes were included. RESULTS: A total of 206 cases of CH (0·83 per 1000 births) and 170 cases of non-NTD CH (0·69 per 1000 births) were recorded in the study. The prevalence of CH and non-NTD CH was higher in women in the no supplementation group than those in the FA supplementation group (0·92 and 0·72 v. 0·75 and 0·65 per 1000 births, respectively). FA supplementation during the periconceptional period significantly prevented CH (OR = 0·29, 95 % CI 0·12, 0·69) and non-NTD CH (OR = 0·34, 95 % CI 0·12, 0·97) in northern China, especially in a high-compliance group (≥ 80 %). CONCLUSIONS: Periconceptional FA supplementation did not significantly prevent CH overall in the current study. However, in the north of China with common maternal folate insufficiency, there was some evidence.

Maternal periconceptional body mass index and risk for neural tube defects: results from a large cohort study in China.

Background: Case-control studies have consistently suggested an association between pre- or periconceptional maternal obesity and an increased risk for neural tube defects (NTDs). Few studies have examined the association between body mass index (BMI) and NTDs using measured weight and height. We examined this association in a large cohort study in China.Methods: We used data from a large population-based cohort study established to evaluate the effectiveness of folic acid supplementation to prevent NTDs in China. BMI was computed using maternal weight and height measured before pregnancy or during early pregnancy. External birth defects were identified through a unique birth defects surveillance system. We estimated the birth prevalence and prevalence odds ratios (POR) for NTDs by Chinese BMI categories, controlling for potential confounders.Results: Our study population included a total of 194,844 women. We observed significantly elevated risk for spina bifida (adjusted POR = 5.4, 95% CI: 1.3-22.5) among children born to obese compared to normal weight women. Among women who took folic acid supplements, the adjusted POR for spina bifida among obese women was 10.0 (95% CI: 2.3-42.6) compared to pill users who were of normal weight. Borderline significantly elevated risk was observed for anencephaly (adjusted POR = 1.8; 95% CI: 1.0-3.2) among children born to underweight compared to normal weight women.Conclusions: Our findings suggest that maternal periconceptional obesity may be associated with an increased risk for spina bifida. Maternal underweight may be associated with increased risk for anencephaly.

Association between tea drinking and plasma folate concentration among women aged 18-30 years in China.

OBJECTIVE: Association was found between tea and neural tube defects. However, few studies investigated the relationship between tea consumption and blood folate levels. We aimed to investigate the association between tea consumption and plasma folate concentrations among women aged 18-30 years in different ethnicities of China. DESIGN: Data were obtained from a national cross-sectional study conducted from 2005 to 2006 of women aged 18-30 years in China. Socio-demographic characteristics and lifestyle were obtained from a questionnaire. Dietary folate intake was determined by 24-h dietary recall. Plasma folate concentrations were measured by a microbiological assay. Multiple linear regression model was used to calculate partial regression coefficients after adjusting for confounding factors. SETTING: Nine provinces or autonomous regions in China. PARTICIPANTS: A total of 2932 women aged 18-30 years in China. RESULTS: After stratifying by ethnicity and tea type, tea consumption was significantly positively associated with plasma folate levels in Han women who drank unfermented tea weekly (ß = 0·067, and P = 0·037) or daily (ß = 0·119, and P = 0·031) and in Uighur women who drank fermented tea weekly (ß = 0·325, and P = 0·028). For women who drank unfermented tea in Han ethnicity, weekly and daily tea drinkers had 6·77 % (95 % CI: 6·36 %, 7·21 %) and 7·13 % (95 % CI: 6·40 %, 7·96 %) increase in plasma folate concentration compared with no tea drinkers. CONCLUSIONS: There is a suggestion of possible positive association between unfermented tea drinking in Han ethnicity and plasma folate concentrations, for Chinese women aged 18-30 years. The relationship between tea drinking in other ethnic groups and plasma folate still needs to be further explored.