BACKGROUND: It has been reported that prenatal metal exposure is associated with child anthropometry. However, studies focusing on the growth rate of anthropometry among children have not been conducted. This study aimed to examine associations between the exposure of multiple metals during pregnancy and the growth rate of anthropometry among offspring.
METHODS: 743 mother-child pairs from the Hangzhou Birth Cohort Study (HBCS) were included. Levels of eleven metals in mother\'s blood during pregnancy were measured. Offspring had a mean of 5.7 measurements on anthropometric indicators including weight, length/height, head circumference, and body mass index (BMI) within 1.5 years of birth. Generalized estimating equation (GEE) model was used to investigate the associations between maternal metal exposure and growth rate of anthropometric indicators in children. Stratification analysis by sex was also examined.
RESULTS: Levels of selenium (Se, β = 0.213, 95 % CI = 0.017 to 0.409, P = 0.033) were positively associated with length/height gain per month in children. Levels of chromium (Cr, β = 0.025, 95 % CI = 0.018 to 0.033, P < 0.001) were positively associated with the rate of weight gain. Levels of manganese (Mn, β = -0.030, 95 % CI = -0.052 to -0.008, P = 0.009) and cobalt (Co, β = -0.012, 95 % CI = -0.024 to -0.000, P = 0.044) were inversely associated with growth rate of head circumference. Children with higher maternal Mn levels had a lower BMI change rate. Associations between metals and growth rate were stronger in girls than in boys. Besides, significant associations between metal mixtures and growth rate were found.
CONCLUSIONS: Prenatal exposure to Se, Cr, Mn, and Co was associated with growth rate in children, with sex-specific disparities. Our results suggested important effects of maternal exposure to multiple metals on development in offspring.

To the best of our knowledge, prior research has yet to delve into the combined and interactive relationships between maternal exposure to essential elements and toxic metals and infancy\'s continuous growth and trajectories. This study aims to discern infant growth trajectories in the first year of life and to determine the associations of maternal serum levels of essential elements and toxic metals with growth trajectory. Within a Chinese prospective cohort in 2019 - 2021, 407 mother-infant pairs were included, and the serum levels of five essential elements (zinc, calcium, copper, magnesium and iron) and two toxic metals (cadmium and lead) in early pregnancy were assessed. The growth trajectory of infants was followed until age one year. Raw BMI and height values were transformed to age- and sex-specific BMI and height standard deviation (SD) scores. Latent-class group-based trajectory models and piecewise linear mixed regression were estimated to determine infant growth trajectories and growth velocity, respectively. The individual relationship between maternal metallic element levels and infant growth trajectory was examined using multinomial logistic regression models and linear mixed regression, while joint associations and interactive relationships were explored using Bayesian kernel machine regression (BKMR) following confounder adjustments. Four distinct trajectory patterns based on BMI-z score (low-rapid BMI gain group, normal-stable BMI group, very low-rapid BMI gain group and normal-rapid BMI gain group) and length-for-age (high-stable length group, low-stable length group, normal-rapid length gain group, very low-rapid length gain group) were identified during the first year post-birth, respectively. In single-metal and multiple-metal models, infants born to mothers with higher serum Zn and lower serum Cu levels were associated with a normal-rapid BMI gain trajectory during the first year. Serum Cu exhibited a positive correlation with the rate of BMI change solely in infants aged 6-12 months. Further, the BKMR analysis revealed a statistically significant and negative joint effect of the five essential elements on the likelihood of normal-rapid BMI/length gain trajectory when serum levels of these elements fell below the 70th percentile compared to median levels. In addition, high levels of serum copper and calcium interactively affect the rates of BMI change during 6-12 months old (β: -0.21, 95% CI: -0.44, -0.03, P = 0.04, P-interaction=0.04). In conclusion, maternal trace elements at early pregnancy are linked to infant growth patterns and growth velocity in the first year of life.

Exploration of stage-specific effects of maternal exposure to trace elements and toxic metals on infancy continuous growth and trajectories is critical for early-life health management. Within a Chinese prospective cohort in 2014-2015, a total of 919 mother-infant pairs were included, and the urinary levels of 17 elements including vanadium (V), chromium (Cr), manganese, iron, cobalt, nickel, copper, zinc, arsenic, molybdenum, palladium, cadmium, tin, gold, mercury, thallium, and lead in early (mean: 11.9 weeks), and late pregnancy (mean: 32.4 weeks) were assessed. Standardized anthropometric assessments of infants were conducted at 1, 3, 6, 8, and 12 months of age. A three-step longitudinal and high-dimensional data analysis procedure was carried out to estimate the impacts of exposome on dynamic growth. Early-pregnancy exposures to V and Cr were positively associated with repeated measurements of length-for-age z-scores (LAZ). Six trajectories were identified based on LAZ. Maternal single exposure to V and Cr as well as mixed exposure to trace elements in early pregnancy were associated with raised odds for the high-stable group. Our results suggested positive associations between maternal trace element exposome and infancy dynamic growth. V and Cr were the key elements and the early pregnancy might be the critical window.

To evaluate the relationship between infant age of egg introduction and malnutrition-related growth outcomes in the United States, we analysed secondary data of 1716 mother-child dyads in the Infant Feeding Practices Study II and its Year 6 Follow-Up Study. Malnutrition-related growth outcomes included body mass index z-score (BMIZ), obesity (weight-for-height z-score [WHZ] ≥3 or BMIZ ≥ 2), WHZ, wasting (WHZ < -2), height-for-age z-score (HAZ), and stunting (HAZ < -2). Infant age at egg introduction was analysed as a continuous variable. We used generalised estimating equations to estimate the mean difference in continuous outcomes and relative risk [RR]) for binary outcomes, adjusting for related maternal and child confounders. We also explored interactions with child sex, maternal race/ethnicity, maternal educational level, ever breastfeeding, and formula feeding. In the total sample, a later infant age at egg introduction was associated with a lower mean difference in HAZ (confounder-adjusted mean difference = -0.08, 95% confidence interval [CI]: -0.12 to -0.03 per month) and a higher risk of stunting (confounder-adjusted RR = 1.17, 95% CI: 1.03-1.33 per month) at 6 years. The associations between infant age at egg introduction and 12-month growth outcomes differed by child sex. Among females but not among males, later introduction of eggs was associated with a lower mean WHZ (-0.06 [-0.12 to 0.00] per month) at 12 months. Later egg introduction during infancy was associated with a lower mean HAZ and a higher risk of stunting in 6-year-old children. Besides this, it was associated with a lower WHZ among females at 12 months.

Phthalates are a series of widely used chemicals that demonstrate to be endocrine disruptors and are detrimental to human health. Phthalates can be found in most products that have contact with plastics during producing, packaging, or delivering. Despite the short half-lives in tissues, chronic exposure to phthalates will adversely influence the endocrine system and functioning of multiple organs, which has negative long-term impacts on the success of pregnancy, child growth and development, and reproductive systems in both young children and adolescents. Several countries have established restrictions and regulations on some types of phthalates; however, we think that more countries should establish constraints or substitute measures for phthalates to reduce health risks. This article aims to summarize the adverse impacts of phthalates on human health, analyze the toxicity mechanism, assess the risks, and finally provide feasible strategies to reduce exposure of the public to phthalates.

This study provides information on food insecurity and child malnutrition in a technologically advanced nation.
Population-based study using multistage probability cluster sampling design to collect survey data. Multivariable regression models were used to determine associations between food security status and various malnutrition indices.
We used a national sample from the US National Health and Nutrition Examination Survey 2011-2014.
The anthropometric and demographic data sets of 4121 children <7 years old were analysed for this study.
Food-insecure infants younger than 6 months had shorter upper arm length (-0·4 cm, P = 0·012) and smaller mid-upper arm circumference (-0·5 cm, P = 0·004); likewise those aged 6 months-1 year had shorter upper arm length (-0·4 cm, P = 0·008), body length (-1·7 cm, P = 0·007) and lower body weight (-0·5 kg, P = 0·008). Food-insecure children younger than 2 years were more likely to be underweight (OR: 4·34; 95 % CI 1·99, 9·46) compared with their food-secure counterparts. Contrariwise, food-insecure children older than 5 years were more likely to be obese (OR: 3·12; 95 % CI 1·23, 7·96).
Food insecurity associates with child growth deficits in the USA. Food-insecure infants and young children are generally smaller and shorter, whereas older children are heavier than their food-secure counterparts, implying a double burden of undernutrition-overnutrition associated with child food insecurity. Child food and nutrition programmes to improve food insecurity should focus on infants and children in the transition ages.

OBJECTIVE: Approximately 165 million children aged <5 years are at risk of low height-for-age. This study explored whether water quality and distance to water source affected short- and long-term growth, and the critical time windows of such effects.
METHODS: This study used data from the China Health and Nutrition Survey (CHNS), which was a cohort study performed in 15 Chinese provinces.
METHODS: Data from the CHNS between 1989 and 2011 were examined. Three cohorts of children who were enrolled at 0-2 years of age in 1989, 1993, and 2000 provided sufficient data for this study. Child height was measured by physicians, and household water supply, including the water quality (safe or unsafe) and distance to the source (in-yard or out-yard), was assessed using a questionnaire when the children were 0-2, 4-6, and 11-13 years of age. Multiple regressions were performed to analyse the associations between water quality and distance to the source at various ages, and height at that age and older ages, with and without adjusting for the household water supply at previous ages. Multiple informant models were created using a generalised estimating equation and these were used to assess whether the exposure coefficients were equal across the three age periods.
RESULTS: A total of 1192 children were included. Water quality was not significantly associated with height over the three age periods. An out-yard water source at the age of 0-2 years was not associated with child height at that age, but it was inversely associated with child height at ages 4-6 and 11-13 years (β = -1.605, 95% confidence interval [CI]: -2.490 to -0.720, and β = -2.817, 95% CI: -4.411 to -1.224, respectively), after adjusting for sociodemographic and economic covariates and baseline child height. Distance to the water source at age 4-6 and 11-13 years was not significantly associated with height. However, significant differences were observed in the associations between distance to water source across the three age periods and height at age 4-6 and 11-13 years (pint = 0.064 and 0.069, respectively).
CONCLUSIONS: Distance to the water source in early, but not later, childhood exerted a long-term effect on child height. When the water quality is good, efforts should be made to shorten the distance to the source to improve child health and growth.

Exposure to atmospheric fine particle matter (PM2.5) pollution and the absorbed pollutants is known to contribute to numerous adverse health effects in children including to growth.
The aim of this study was to evaluate exposure levels of atmospheric PM2.5-bound polycyclic aromatic hydrocarbons (PAHs) in an electronic waste (e-waste) polluted town, Guiyu, and to investigate the associations between PM2.5-PAH exposure, insulin-like growth factor 1 (IGF-1) levels and child growth.
This study recruited 238 preschool children (3-6 years of age), from November to December 2017, of which 125 were from Guiyu (an e-waste area) and 113 were from Haojiang (a reference area). Levels of daily PM2.5 and PM2.5-bound ∑16 PAHs were assessed to calculate individual chronic daily intakes (CDIs). IGF-1 and IGF-binding protein 3 (IGFBP-3) concentrations in child plasma were also measured. The associations and further mediation effects between exposure to PM2.5 and PM2.5-bound PAHs, child plasma IGF-1 concentration, and child height were explored by multiple linear regression models and mediation effect analysis.
Elevated atmospheric PM2.5-bound ∑16 PAHs and PM2.5 levels were observed in Guiyu, and this led to more individual CDIs of the exposed children than the reference (all P < 0.001). The median level of plasma IGF-1 in the exposed group was lower than in the reference group (91.42 ng/mL vs. 103.59 ng/mL, P < 0.01). IGF-1 levels were negatively correlated with CDIs of PM2.5, but not with CDIs of PM2.5-bound ∑16 PAHs after adjustment. An increase of 1 μg/kg of PM2.5 intake per day was associated with a 0.012 cm reduction of child height (95% CI: -0.014, -0.009), and similarly, an elevation of 1 ng/kg of PM2.5-bound ∑16 PAHs intake per day was associated with a 0.022 cm decrease of child height (95% CI: -0.029, -0.015), both after adjustment of several potential confounders (age, gender, family cooking oil, picky eater, eating sweet food, eating fruits or vegetables, parental education level and monthly household income). The decreased plasma IGF-1 concentration mediated 15.8% of the whole effect associated with PM2.5 exposure and 23.9% of the whole effect associated with PM2.5-bound ∑16 PAHs exposure on child height.
Exposure to atmospheric PM2.5-bound ∑16 PAHs and PM2.5 is negatively associated with child height, and is linked to reduced IGF-1 levels in plasma. This may suggest a causative negative role of atmospheric PM2.5-bound exposures in child growth.

OBJECTIVE: To study the introducing time of complementary food in poor rural areas and its association with the growth of infants and young children.
METHODS: In total of 1802 infants and young children aged 6-12 months from 11 poverty counties in southern Shaanxi Province were selected by stratified random cluster sampling. These infants were surveyed four times, and once every 6 months. Data on complementary feeding for children were collected through the questionnaires. Cognitive development was measured by BSID. Body weight and length for them were measured using standard gauges to generate height for age Z score( HAZ), weight for age Z score( WAZ) and weight for height Z score( WHZ). The analysis of variance was used to identify the association between the introducing time of complementary food and growth of children.
RESULTS: at baseline, only 32. 93% of children were introduced complementary food at the age of 6 months. This study indicated that the introducing time of complementary food was significantly associated with the cognitive development in the longer run. The third and fourth survey showed that children with introducing complementary food after 6 months of age( mental development index were 81. 24 and78. 40 respectively) had significantly lower cognitive development ability( F = 11. 86, P<0. 05; F = 4. 24, P< 0. 05). There were no long-term significant correlation between the introducing time of complementary food and WAZ, HAZ and WHZ.
CONCLUSIONS: There are still lots of children that were not feeding reasonably in poor rural China. The introducing time of complementary food is related to growth of infants and young children.

BACKGROUND: Fetal macrosomia, defined as birth weight equal or over 4000 g, is a major concern for both neonatal and maternal health. A rapid increasing trend in fetal macrosomia is observed in different regions of China. We aimed to examine the association between fetal macrosomia and risk of childhood obesity in Western China.
METHODS: All macrosomic live singletons (≥ 4000 g), and a random sample of singletons with normal birth weight (2500-3999 g) born in four districts of Chengdu, Western China, in 2011 were included in the cohort study. Maternal demographics, obstetric factors, labor and delivery summary at baseline were extracted from the Chengdu Maternal and Child Health Management System. Anthropometric measurements before 3 years and infant feeding information at around 6 months were also collected. Childhood obesity under 3 years was primarily defined as a weight-for-length/height z score ≥ 1.645 using the WHO growth reference. Secondary definitions were based on weight-for-age and body mass index (BMI)-for-age over the same cut-offs.
RESULTS: A total of 1767 infants were included in the analyses, of whom 714 were macrosomic. After controlling for maternal age, parity, gestational age and anemia at the first antenatal visit, pre-pregnancy BMI, gestational weight gain, gestational age at birth, baby age and sex, and breastfeeding practices at 6 months, the risk of childhood obesity defined according to weight-for-length/height among macrosomic babies was 1.90 (95% confidence interval 1.04-3.49) times that of babies with normal birth weight. The risk of childhood obesity for macrosomic babies was 3.74 (1.96-7.14) and 1.64 (0.89-3.00) times higher based on weight-for-age and BMI-for-age, respectively.
CONCLUSIONS: Fetal macrosomia is associated with increased risk of obesity in children under 3 years in Western China.