The Association of Folic Acid, Iron Nutrition during Pregnancy and Congenital Heart Disease in Northwestern China: A Matched Case-Control Study.

Background: The purpose of this study was to investigate the relationship between folic acid and iron nutrition during pregnancy and congenital heart disease (CHD) in the offspring. Methods: Conditional logistic regression models and nonlinear mixed-effects models were used to analyze the effects of folic acid and iron nutrition during pregnancy on CHD in offspring. Results: After adjusting for confounders, folic acid or iron supplementation during pregnancy reduced the risk for fetal CHD (OR = 0.60 (0.45, 0.82) or 0.36 (0.27, 0.48)). Similarly, dietary iron intake during pregnancy (≥29 mg/d) was associated with a reduced risk of fetal CHD (OR = 0.64 (0.46, 0.88)). Additionally, compared with women who only supplemented folic acid (OR = 0.59 (0.41, 0.84)) or iron (OR = 0.32 (0.16, 0.60)), women who supplemented both folic acid and iron had lower risk for newborns with CHD (OR = 0.22 (0.15, 0.34)). Similarly, compared with women who only supplemented folic acid (OR = 0.59 (0.41, 0.84)) or higher dietary iron intake (≥29 mg/d) (OR = 0.60 (0.33, 1.09)), women who supplemented both folic acid and higher dietary iron intake (≥29 mg/d) had lower risk for the newborn with CHD (OR = 0.41 (0.28, 0.62)). The combined effects were significant in the multiplication model (OR = 0.35 (0.26, 0.48) or 0.66 (0.50, 0.85)) but not in the additive model. Conclusions: Our study found that folic acid and iron nutrition during pregnancy were associated with a reduced risk of CHD in the offspring and confirmed a statistically significant multiplicative interaction between folic acid and iron nutrition on the reduced risk of CHD in offspring.

Risk Assessment for Birth Defects in Offspring of Chinese Pregnant Women.

OBJECTIVE: This study aimed to develop a nomogram for the risk assessment of any type of birth defect in offspring using a large birth-defect database in Northwest China. METHODS: This study was based on a birth-defect survey, which included 29,204 eligible women who were pregnant between 2010 and 2013 in the Shaanxi province of Northwest China. The participants from central Shaanxi province were assigned to the training group, while the subjects from the south and north of Shaanxi province were assigned to the external validation group. The primary outcome was the occurrence of any type of birth defect in the offspring. A multivariate logistic regression model was used to establish a prediction nomogram, while the discrimination and calibration were evaluated by external validation. RESULTS: The multivariate analyses revealed that household registration, history of miscarriages, family history of birth defects, infection, taking medicine, pesticide exposure, folic acid supplementation, and single/twin pregnancy were significant factors in the occurrence of birth defects. The area under the receiver operating characteristic curve (AUC) in the prediction model was 0.682 (95% CI 0.653 to 0.710) in the training set. The validation set showed moderate discrimination, with an AUC of 0.651 (95% CI 0.614 to 0.689). Additionally, the prediction model had a good calibration (HL χ2 = 8.106, p= 0.323). CONCLUSIONS: We developed a nomogram risk model for any type of birth defect in a Chinese population based on important modifying factors in pregnant women. This risk-prediction model could be a tool for clinicians to assess the risk of birth defects and promote health education.

Investigation of selenium nutritional status and dietary pattern among children in Kashin-Beck disease endemic areas in Shaanxi Province, China using duplicate portion sampling method.

BACKGROUND AND OBJECTIVES: Selenium deficiency is a primary risk factor of Kashin-Beck disease (KBD). This study aimed to investigate whether children in endemic areas could maintain sufficient selenium intake after termination of selenium supplement administration, and evaluate their comprehensive nutritional status and dietary structure. METHODS: Duplicate portion sampling combined with a questionnaire was adopted to collect data on categories and quantity of all food ingested in three consecutive days. Occipital hair was also collected to detect selenium content by hydride generation atomic fluorescence spectrometry (HGAFS). CDGSS3.0 software and factor analysis were integrated to assess the children's comprehensive nutritional status and dietary structure. RESULTS: This study included 240 sex-matched (1:1) children aged 7-12 years from KBD endemic (n = 120) and non-endemic (n = 120) areas. Overall, 720 solid food, 720 liquid, and 240 hair samples were collected for selenium determination. The mean selenium level in hair of children in endemic areas (0.38 ± 0.16 mg/kg) was significantly lower than that in children in non-endemic areas (0.56 ± 0.28 mg/kg, Z = -5.249, p < 0.001). The dietary selenium intake of children in endemic areas was 40.0% lower than that in children in non-endemic areas (Z = -9.374, p < 0.001). Children in endemic areas consumed significantly less diverse dietary items leading to significantly less intake of multiple nutrients compared to children in non-endemic areas. CONCLUSIONS: The dietary selenium intake of most children in endemic areas was less than the recommended amount. The dietary structure of children was undiversified, which limited the intake of multiple nutrients. Therefore, comprehensive nutrition rather than sole selenium intake should be the primary concern in the future.

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 (Pinteraction = 0.060). CONCLUSIONS: Maternal vitamin B complex supplementation during pregnancy was associated with better neonatal vitamin B12 status in rural northwest China.

Effect of maternal pre-pregnancy underweight and average gestational weight gain on physical growth and intellectual development of early school-aged children.

The aim of this study was to assess the effect of low maternal weight at pre-pregnancy and the average gestational weight gain on undernourished children and their intellectual development. From October 2012 to September 2013, we followed 1744 offspring of women who participated in a trial conducted from 2002 to 2006. Pregnant women recruited in the original trial could receive three prenatal health checks for free, at which maternal weight and height were measured. WISC-IV was used to estimate the intellectual development of children. Weight and height of both pregnant women and children were measured by trained anthropometrists using standard procedures. Having low maternal weight at pre-pregnancy was associated with an increased risk of undernutrition amongst children (underweight: OR = 2.02, 95%CI: 1.14-3.56, thinness: OR = 2.79, 95%CI: 1.50-5.17) and a decrease in verbal comprehension index (-2.70 points, 95%CI: -4.95-0.44) of children. The effect of average gestational weight gain on occurrences of underweight children (OR = 0.08, 95%CI: 0.01-0.55) was also found. We identified the effect of maternal pre-pregnancy underweight on impairment of the separate intellectual domains (verbal comprehension index) and increasing occurrence of undernourished children. Average gestational weight gain was positively associated with a decreased prevalence of underweight children but not with the intellectual development of children in rural China.

Maternal iron intake during pregnancy and birth outcomes: a cross-sectional study in Northwest China.

Previous studies have yielded conflicting results on the associations of maternal Fe intake with birth outcomes. This study aimed to investigate the associations between maternal Fe intake (total Fe from diet and supplements, dietary total Fe, haeme Fe, non-haeme Fe and Fe supplements use) and adverse birth outcomes in Shaanxi Province of Northwest China. In all, 7375 women were recruited using a stratified multistage random sampling method at 0-12 months (median 3; 10th-90th percentile 0-7) after delivery. Diets were collected by a validated FFQ and maternal characteristics were obtained via a standard questionnaire. The highest tertile of haeme Fe intake compared with the lowest tertile was negatively associated with low birth weight (LBW) (OR 0·68; 95 % CI 0·49, 0·94), small for gestational age (SGA) (OR 0·76; 95 % CI 0·62, 0·94) and birth defects (OR 0·55; 95 % CI 0·32, 0·89). Maternal haeme Fe intake was associated with a lower risk of intra-uterine growth retardation (IUGR) (medium tertile v. lowest tertile: OR 0·78; 95 % CI 0·61, 0·95; highest tertile v. lowest tertile: OR 0·76; 95 % CI 0·59, 0·93; P trend=0·045). The OR of LBW associated with Fe supplements use were as follows: during pregnancy: 0·72 (95 % CI 0·50, 0·95); in the second trimester: 0·67 (95 % CI 0·42, 0·98); in the third trimester: 0·47 (95 % CI 0·24, 0·93). We observed no associations of total Fe, dietary total Fe or non-haeme Fe intake with birth outcomes. The results suggest that maternal haeme Fe intake is associated with a reduced risk of LBW, SGA, IUGR and birth defects, and Fe supplements use during pregnancy reduces LBW risk.

Maternal Prenatal Nutrition and Birth Outcomes on Malnutrition among 7- to 10-Year-Old Children: A 10-Year Follow-Up.

OBJECTIVES: To identify postnatal predictors of malnutrition among 7- to 10-year-old children and to assess the long-term effects of antenatal micronutrient supplementation on malnutrition. STUDY DESIGN: A follow-up study was conducted to assess the nutritional status of 7- to 10-year-olds (1747 children) whose mothers participated in a cluster-randomized double-blind controlled trial from 2002 to 2006. RESULTS: The rate of malnourished 7- to 10-year-olds was 11.1%. A mixed-effects logistic regression model adjusted for the cluster-sampling design indicated that mothers with low prepregnant midupper arm circumference had boys with an increased risk of thinness (aOR 2.05, 95% CI 1.11, 3.79) and girls who were more likely to be underweight (aOR 2.01, 95% CI 1.05, 3.85). Antenatal micronutrient supplementation was not significantly associated with malnutrition. Low birth weight was significantly associated with increased odds of malnutrition among boys (aOR 4.34, 95% CI 1.82, 10.39) and girls (aOR 7.50, 95% CI 3.48, 16.13). Being small for gestational age significantly increased the odds of malnutrition among boys (aOR 1.75, 95% CI 1.01, 3.04) and girls (aOR 4.20, 95% CI 2.39, 7.39). In addition, household wealth, parental height, being picky eater, and illness frequency also predicted malnutrition. CONCLUSIONS: Both maternal prenatal nutrition and adverse birth outcomes are strong predictors of malnutrition among early school-aged children. Currently, available evidence is insufficient to support long-term effects of antenatal micronutrient supplementation on children's nutrition. TRIAL REGISTRATION: www.isrctn.com: ISRCTN08850194.

Rapid Infancy Weight Gain and 7- to 9-year Childhood Obesity Risk: A Prospective Cohort Study in Rural Western China.

Obesity is increasing in developing countries. This study aimed to identify the association between rapid infancy weight gain and obesity risk among early school-age children. A total of 581 singletons (349 boys, 232 girls) whose mothers participated in an antenatal multiple micronutrient supplement trial in rural western China were followed from birth to between 7 and 9 years of age. Height and weight were measured at birth, 1.5 years, and between 7 and 9 years. At the 7- to 9-year time point, body composition was determined using bioelectrical impedance analysis. Multilevel mixed analysis was used to test the associations between rapid weight gain in infancy (from birth to age 1.5 years) and body size and composition or overweight/obesity among early school-age children. Overall, 31.2% (181 of 581) of the infants showed a weight-for-age Z score gain greater than 0.67 between birth and 1.5 years, indicating rapid weight gain. Approximately 5.7% (33 of 579) of the subjects were overweight (BMI-for-age Z scores [BAZ] >1 and ≤2) or obese (BAZ >2). Rapid infancy weight gain was associated with a higher BAZ (P < 0.001), mid-upper arm circumferences (P < 0.001), percentage body fat (P < 0.001), and fat mass index (P < 0.001) at 7 to 9 years of age after adjusting for biological and social economic factors, genetic factors, and perinatal and postnatal factors. These associations appeared to be independent of gender, economic status at early school age, and maternal nutritional status at enrollment. Rapid growers may have approximately 3 times the risk of being overweight/obese during the early school-age years (odds ratio = 2.94, 95% CI: 1.17-7.43, P = 0.022). Rapid infancy weight gain is a risk factor for being overweight/obesity among early school-age children in rural western China. We propose that social and biological determinants, such as economic status, physical activity, and feeding practice, should be targeted to prevent obesity.