Birth Cohort Study In China Research Articles

Associations of Placental Inflammation and Oxidative Stress Biomarkers with Glucolipid Metabolism in Children: A Birth Cohort Study in China.

The maternal intrauterine immune environment may affect offspring long-term health. We aimed to investigate the association between the intrauterine placental immunological milieu and glycolipid metabolic health in children. This study enrolled 1803 mother-child pairs from the Ma'anshan birth cohort (2013-2014). Placental mRNA expression of inflammatory cytokines (interleukin-1β [IL-1β], IL-10, monocyte chemoattractant protein-1, tumor necrosis factor-α, IL-4, IL-6, IL-8, C-reactive protein, and interferon-γ) and oxidative stress biomarkers (heme oxygenase-1, hypoxia-inducible factor-1alpha, and glucose-related protein 78) was quantified using real-time quantitative polymerase chain reaction. Fasting blood glucose, insulin, triglycerides, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and total cholesterol were assessed at 5 to 6 years old. Statistical analyses included multiple linear regression, binary logistic regression, restricted cubic spline model, and the Bayesian kernel machine regression model. Placental inflammatory cytokines (IL-1β, monocyte chemoattractant protein-1, C-reactive protein, IL-6, IL-8, IL-10) and oxidative stress biomarkers (heme oxygenase-1, hypoxia-inducible factor-1alpha, glucose-related protein 78) showed positive associations with children's fasting blood glucose levels. Heme oxygenase-1 and glucose-related protein 78 exhibited negative correlations with children's fasting insulin levels. Elevated IL-6, heme oxygenase-1, hypoxia-inducible factor-1alpha, and glucose-related protein 78 were associated with increased risk of prediabetes in children. Overall upregulation of placental proinflammatory cytokines and oxidative stress factors mRNA expression correlated with higher prediabetes risk in children. Bayesian kernel machine regression analysis indicated a joint positive effect of the 12 placental inflammation and oxidative stress mixtures on children's risk of high fasting blood glucose. This exploratory study underscores significant correlations between maternal intrauterine placental inflammation, oxidative stress markers, and offspring fasting blood glucose and insulin levels. These findings highlight the potential role of intrauterine holistic immunity in shaping offspring glucose metabolism health.

Preconception underweight and the risk of offspring congenital heart diseases in young pregnant women: Evidence from the China Birth Cohort Study.

Maternal obesity is a highly suggestive risk factor of offspring congenital heart diseases (CHD). However, the risk of offspring CHD associated with maternal underweight has rarely been mentioned. Therefore, this study aimed to explore the effect of preconception underweight on offspring CHD. From November 2017 to August 2021, 132 386 pregnant women were enrolled in a birth cohort study in China in early pregnancy, and completed follow-up until delivery (or miscarriage/termination). Offspring CHD was diagnosed by prenatal ultrasound examination in both live births and stillbirths. Log-binomial regression and restricted cubic spline were used to estimate the risk of offspring CHD associated with preconception body mass index (BMI). A generalized additive model was used to explore the modification effect of maternal age on the association between preconception BMI and offspring CHD. A total of 129 096 pregnant women were included in the analysis. The incidence of CHD in the underweight, normal weight, overweight, and obesity groups were 117/17 313 (0.68%), 556/85 695 (0.65%), 128/19 936 (0.64%), 47/6152 (0.76%), respectively. Both underweight and obesity before pregnancy marginally increased the risk of offspring CHD. The association between preconception BMI and offspring CHD varied by maternal age, with low preconception BMI associated with a significantly higher risk of offspring CHD in women <24 years (RR 2.32, 95% CI: 1.07-5.01 for 17 vs 21 kg/m2). Preconception underweight was associated with an increased risk of offspring CHD in young pregnant women. Therefore, weight gain is important to prevent offspring CHD, especially for young women with low preconception BMI.

Association between lipid profile in early pregnancy and the risk of congenital heart disease in offspring: a prospective cohort study

This study aimed to investigate the association of lipid profile in early pregnancy and the risk of congenital heart disease (CHD) in offspring. This study was a prospective cohort design based on the Fujian Birth Cohort Study in China. We recruited pregnant women at ≤ 14 weeks of gestation between 2019 and 2022, and all participants in this study filled out the questionnaire about periconceptional exposure. Simultaneously, we collected participants’ fasting blood samples to measure their lipid profile by automatic biochemical analyzer. The outcome was defined as offspring with CHD. A multivariable logistic regression model was used to calculate adjusted odds ratio (AOR) risk estimates, which indicate the associations between maternal lipid profiles and CHD in offspring. Restricted cubic splines were used to estimate their nonlinear relationship. A total of 21,425 pregnant women with an average gestational age of 11.3 (± 1.40) weeks were included in the analysis. The higher triglyceride (AOR 1.201, 95% CI [1.036, 1.394]), low-density lipoprotein (AOR 1.216, 95% CI [1.048, 1.410]), apolipoprotein B (Apo B) (AOR 2.107, 95% CI [1.179, 3.763]) levels were correlated with increased odds of CHD in offspring, while high-density lipoprotein (OR 0.672, 95% CI [0.490, 0.920]) related with decreased odds of CHD in offspring. The restricted cubic spline suggested a nonlinear relationship between total cholesterol (TC) levels and the risk of CHD in offspring (P = 0.0048), but no significant nonlinear relationships were found in other lipid profile. Apolipoprotein A was not related to the risk of CHD in offspring as either a continuous variable or a hierarchical variable. Elevated lipid profile in early pregnancy levels are associated with an increased risk of CHD in offspring. Additionally, there is a non-linear relationship between TC levels and the risk of CHD in offspring.

Prenatal Exposure to Bisphenols and Visual Impairment in Preschool Children: A Prospective Birth Cohort Study in China

Prenatal Exposure to Bisphenols and Visual Impairment in Preschool Children: A Prospective Birth Cohort Study in China

Association of Breastfeeding and Neonatal Jaundice With Infant Neurodevelopment

IntroductionExclusive breastfeeding is advantageous for infant neurodevelopment. Nevertheless, insufficient human milk supply in exclusively breastfed infants may elevate the risk of neonatal jaundice, which can potentially result in neurological harm. Whether mothers should adhere to exclusive breastfeeding in infants with neonatal jaundice remains unclear. MethodsData comes from the Jiangsu Birth Cohort (JBC), a prospective and longitudinal birth cohort study in China. A total of 2577 infants born from November 2017 to March 2021 were included in the analysis. Multivariate linear regression models were used to analyze the associations between breastfeeding status, neonatal jaundice, and their interaction with infant neurodevelopment. Analysis was performed in 2022. ResultsCompared with “exclusive breastfeeding”, fine motor scores of infants were lower for “mixed feeding” (βadj, -0.16; 95% CI, -0.29 to -0.03; P = 0.016) and “no breastfeeding” (βadj, -0.41; 95% CI, -0.79 to -0.03; P = 0.034). Compared with “no neonatal jaundice”, infants with “severe neonatal jaundice” had lower scores for cognition (βadj, -0.44; 95% CI, -0.66 to -0.23; P <0.001) and fine motor (βadj, -0.19; 95% CI, -0.35 to -0.03; P = 0.024). In infants with severe neonatal jaundice, the termination of exclusive breastfeeding before six months was associated with worse cognition (βadj, -0.28; 95% CI, -0.57 to 0.01), while this association was not observed in those without neonatal jaundice (βadj, 0.09; 95% CI, -0.26 to 0.43). ConclusionsExclusive breastfeeding for the first six months is beneficial to the neurodevelopment of infants, especially in those with severe neonatal jaundice.

Associations of prenatal exposure to bisphenols with BMI growth trajectories in offspring within the first two years: evidence from a birth cohort study in China.

Prenatal bisphenol exposure has been reported to be associated with lower birth weight and obesity-related indicators in early childhood. These findings warrant an investigation of the relationship between prenatal bisphenol exposure and the dynamic growth of offspring. This study aimed to evaluate the relationship of maternal bisphenol concentration in urine with the body mass index (BMI) growth trajectory of children aged up to twoyears and to identify the critical exposure periods. A total of 826 mother-offspring pairs were recruited from Wuhan Children's Hospital between November 2013 and March 2015. Maternal urine samples collected during the first, second, and third trimesters were analyzed for bisphenol A (BPA), bisphenol S, and bisphenol F (BPF) concentrations. Measurements of length and weight were taken at 0, 1, 3, 6, 8, 12, 18, and 24months. Children's BMI was standardized using the World Health Organization reference, and group-based trajectory modeling was used to identify BMI growth trajectories. The associations between prenatal bisphenol exposure and BMI growth trajectory patterns were assessed using multinomial logistic regression models. The BMI growth trajectories of the 826 children were categorized into four patterns: low-stable (n = 134, 16.2%), low-increasing (n = 142, 17.2%), moderate-stable (n = 350, 42.4%), and moderate-increasing (n = 200, 24.2%). After adjusting for potential confounders, we observed that prenatal exposure to BPA during the second trimester [odds ratio (OR) = 2.20, 95% confidence interval (CI) = 1.09-4.43] and BPF during the third trimester (OR = 3.28, 95% CI = 1.55-6.95) at the highest quartile concentration were associated with an increased likelihood of the low-increasing BMI trajectory. Furthermore, in the subgroup analysis by infant sex, the positive association between the highest quartile of prenatal average urinary BPF concentration during the whole pregnancy and the low-increasing BMI trajectory was found only in girls (OR = 2.82, 95% CI = 1.04-7.68). Our study findings suggest that prenatal exposure to BPA and BPF (a commonly used substitute for BPA) is associated with BMI growth trajectories in offspring during the first twoyears, increasing the likelihood of the low-increasing pattern. Video Abstract (MP4 120033kb).

Associations of Trimester-Specific Exposure to Perchlorate, Thiocyanate, and Nitrate with Childhood Neurodevelopment: A Birth Cohort Study in China.

Studies about the impacts of maternal exposure to perchlorate, thiocyanate, and nitrate on offspring neurodevelopment are scarce. Based on a birth cohort in China, 1,028 mothers provided urine samples at three trimesters for determination of the three target analytes, and their offspring neurodevelopment was evaluated at 2 years old. Associations of maternal exposure to the three chemicals with offspring neurodevelopment were estimated using three statistical methods. Trimester-specific analyses using generalized estimating equation models showed that double increment of thiocyanate and nitrate during the first trimester was associated with 1.56 (95% CI: -2.82, -0.30) and 1.22 (-2.40, -0.03) point decreases in the offspring mental development index (MDI), respectively. Weighted quantile sum (WQS) regression analyses showed that the mixture exposure at the first and second trimesters was negatively associated with the offspring MDI (β = -2.39, 95% CI: -3.85, -0.93; β = -1.75, 95% CI: -3.04, -0.47, respectively) and thiocyanate contributed the most to the association (65.0 and 91.6%, respectively). Bayesian kernel machine regression analyses suggested an inverted U-shape relationship of maternal urinary thiocyanate with the offspring MDI. These findings suggested that prenatal exposure to the three chemicals (at current levels), especially thiocyanate and nitrate, may impair neurodevelopment. Early pregnancy seems to be the sensitive window.

Placental inflammatory cytokines mRNA expression and preschool children’s cognitive performance: a birth cohort study in China

BackgroundThe immunologic milieu at the maternal–fetal interface has profound effects on propelling the development of the fetal brain. However, accessible epidemiological studies concerning the association between placental inflammatory cytokines and the intellectual development of offspring in humans are limited. Therefore, we explored the possible link between mRNA expression of inflammatory cytokines in placenta and preschoolers’ cognitive performance.MethodsStudy subjects were obtained from the Ma’anshan birth cohort (MABC). Placental samples were collected after delivery, and real-time quantitative polymerase chain reaction (RT-qPCR) was utilized to measure the mRNA expression levels of IL-8, IL-1β, IL-6, TNF-α, CRP, IFN-γ, IL-10, and IL-4. Children’s intellectual development was assessed at preschool age by using the Wechsler Preschool and Primary Scale of Intelligence, Fourth Edition (WPPSI-IV). Multiple linear regression and restricted cubic spline models were used for statistical analysis.ResultsA total of 1665 pairs of mother and child were included in the analysis. After adjusting for confounders and after correction for multiple comparisons, we observed that mRNA expression of IL-8 (β = − 0.53; 95% CI, − 0.92 to − 0.15), IL-6 (β = − 0.58; 95% CI, − 0.97 to − 0.19), TNF-α (β = − 0.37; 95% CI, − 0.71 to − 0.02), and IFN-γ (β = − 0.31; 95% CI, − 0.61 to − 0.03) in the placenta was negatively associated with preschoolers’ full scale intelligence quotient (FSIQ). Both higher IL-8 and IL-6 were associated with lower children’s low fluid reasoning index (FRI), and higher IFN-γ was associated with lower children’s working memory index (WMI). After further adjusting for confounders and children’s age at cognitive testing, the integrated index of six pro-inflammatory cytokines (index 2) was found to be significantly and negatively correlated with both the FSIQ and each sub-dimension (verbal comprehension index (VCI), visual spatial index (VSI), FRI, WMI, processing speed index (PSI)). Sex-stratified analyses showed that the association of IL-8, IFN-γ, and index 2 with children’s cognitive development was mainly concentrated in boys.ConclusionsEvidence of an association between low cognitive performance and high expression of placental inflammatory cytokines (IL-8, IL-6, TNF-α, and IFN-γ) was found, highlighting the potential importance of intrauterine placental immune status in dissecting offspring cognitive development.

Maternal anxiety during pregnancy and children's asthma in preschool age: The Ma'anshan birth cohort study

BackgroundThe fetal immune system and consequent elevated risk of asthma in childhood may be impacted by maternal anxiety during pregnancy. Limited studies have evaluated whether there was a sensitive period and cumulative effect of the relationship between prenatal anxiety and children's asthma. Methods3131 mother-child pairs made up the study's sample from the Ma'anshan Birth Cohort Study in China. Maternal anxiety status was repeated three times using the pregnancy-related anxiety questionnaire in the 1st, 2nd and 3rd trimesters of pregnancy. Diagnostic information on asthma was collected three times at 24, 36, and 48 months of age. ResultsAfter adjusting for confounders, children born to mothers with anxiety in the 1st, 2nd and 3rd trimesters of pregnancy all had an elevated risk of total asthma from 12 to 48 months of age. After further adjusting prenatal anxiety in the other trimesters, no association was observed between prenatal anxiety in any trimester and preschoolers' asthma. Children of mothers with persistently high anxiety score trajectory during pregnancy had an elevated risk of total asthma and high prevalence trajectory of asthma. Cumulative effects analysis showed that the more frequent the mother's anxiety, the higher the risk of her offspring developing a high prevalence trajectory of asthma from 12 to 48 months of age. The results of the subgroup analysis by age showed similar associations overall. ConclusionsMaternal antenatal anxiety was associated with an elevated risk of preschool children's asthma, and a possible cumulative effect was observed. Maternal mental health conditions during pregnancy should receive constant attention throughout pregnancy, not just during one period.

Associations of cord blood meta-inflammation and vitamin D with neurodevelopmental delay: A prospective birth cohort study in China.

To estimate the associations of cord meta-inflammatory markers with neurodevelopment, including the potential impact of cord blood vitamin D levels. The prospective cohort study comprised 7198 participants based on the Maternal & Infants Health in Hefei study. Cord blood C-peptide, high-sensitive C-reactive protein (hsCRP), high-density lipoprotein-cholesterol, low-density lipoprotein-cholesterol, total cholesterol, triglycerides and 25(OH)D levels were measured. The Gesell Developmental Schedules were used to assess neurodevelopmental outcomes in offspring. After adjusting potential confounders, per quartile increase in cord blood 25(OH)D concentrations was associated with a decreased risk of neurodevelopmental delay [hazard ratios (HR) 0.65 (95% CI 0.57, 0.74)]. Conversely, significant positive associations with cord blood serum C-peptide levels above the 90th percentile [HR 2.38 (95% CI 1.81, 3.13)] and higher levels of cord hsCRP (per quartile increase) [HR 1.18 (95% CI 1.01, 1.37)] with neurodevelopmental delay were observed. These associations could vary by quartiles of cord blood 25(OH)D levels: the adjusted HRs in neurodevelopmental delay comparing children with vs without hyperinsulinemia were 1.28 (95% CI: 1.03, 1.59) for quartiles 1 (lowest), and 1.06 (95% CI: 0.78, 1.44) for quartile 4 (highest). Immune activation and metabolic abnormalities in fetal circulation were associated with neurodevelopmental delay in offspring, which could be attenuated by higher cord blood 25(OH)D levels in a dose-response manner.

Associations of bisphenol exposure with thyroid hormones in pregnant women: a prospective birth cohort study in China.

Bisphenols are endocrine disruptor chemicals that disrupt thyroid hormone homeostasis. However, evidence on the effects of bisphenol mixtures on thyroid hormones are insufficient. Therefore, the present study aimed to explore the effects of bisphenol substitutes and bisphenol mixtures on thyroid hormones during pregnancy. The study was conducted among 446 pregnant women in the Guangxi Zhuang Birth Cohort (GZBC), China. In multiple linear regressions, compared with the low-exposure group, bisphenol S (BPS) concentrations in the middle-exposure group led to a 10.90% (95% CI: - 18.16%, - 2.99%) decrease in triiodothyronine (T3) levels in the first trimester; tetrabromobisphenol A (TBBPA) levels in the middle-exposure group led to an 8.26% (95% CI: - 15.82%, - 0.01%) decrease in T3 levels in the first trimester; bisphenol B (BPB) levels in the middle-exposure group led to higher free thyroxine (FT4) levels (9.84%; 95% CI: 1.73%, 18.60%) in the second trimester; bisphenol F (BPF) in the middle-exposure group led to higher FT4 levels (8.59%, 95% CI: 0.53%, 17.31%) in the second trimester; and TBBPA levels in the high-exposure group led to a 9.39% (95% CI: 1.46%, 17.93%) increase in FT4 levels in the second trimester. The Bayesian kernel machine regression (BKMR) and restricted cubic spline (RCS) models showed a U-shaped dose-response relationship between bisphenol A (BPA) and free triiodothyronine (FT3) (p < 0.01) as well as BPS and FT4 (p < 0.05). Nonlinear relationships were also observed between the bisphenol mixture and FT3. Overall, maternal bisphenol exposure affected thyroid hormone levels during pregnancy. This study provides evidence that BPB, BPF, BPS, and TBBPA are unsafe substitutes for BPA, as well as the overall effect of bisphenols on adverse health in human beings.

Menstrual cycle characteristics as an indicator of fertility outcomes: evidence from prospective birth cohort study in China.

To evidently assess the applicability of regulate menstrual cycle (MC) characteristics in Traditional Chinese Medicine (TCM) as an indicator for fertility. A community-based prospective cohort study was conducted in China. Between January 2010 and December 2012, women who were willing to conceive within 2 years were enrolled in the study. Other than the MC length pattern, a well-adopted MC characteristic, menstrual blood color and clots were specifically concerned for women enrolled. All participants were followed up in 2 years by trained nurses. Pregnancy rate, fecundability odds ratio () and risk of miscarriage were assessed as fertility outcomes. A total of 2109 women were effectively included in this cohort for analysis. Results show that women with irregular MC length were less likely to achieve conception (= 0.59; 95% = 0.45-0.77, < 0.001). Menstrual blood in bright red color was also associated with decline in likelihood of conception ( = 0.79; 95% = 0.63-0.98, = 0.04). Women with menstrual blood in light red were at higher risk of miscarriage ( = 2.39; 95% = 0.91-6.28, = 0.08). No significant impact was found between menstrual blood clots and fertility outcomes ( = 1.02, 95% = 0.83-1.25, = 0.88; = 1.26 95% = 0.77-2.07, = 0.35). MC characteristics can be an effective and simple indicator for women's fertility. Increasing the knowledge of MC characteristics for women in reproductive ages would bring great benefits to their preconception health conditions.

Effects of prenatal exposure to pyrethroid pesticides on neurodevelopment of 1-year- old children: A birth cohort study in China

Pregnant women have been ubiquitously exposed to pyrethroid pesticides. Previous studies, mainly based on third trimester measurements of maternal urinary pyrethroid metabolites, have reported inconsistent findings in the effects of prenatal pyrethroid exposure on children's neurodevelopmental outcomes. The purpose of this study was to clarify if pyrethroid exposure during the entire three trimesters of pregnancy may be associated with deleterious effects on infant neurodevelopmental status, particularly at a high dosage of exposure. We measured maternal urinary concentrations of pyrethroid metabolites in all trimesters of pregnancy and assessed children’s neurodevelopment at one year of age using the Bayley Scales of Infant and Toddler Development, Third Edition (BSID-III). Multiple linear regression models were used to estimate the effects of metabolites (3-PBA, 4 F-3-PBA, cis-DBCA) in each trimester on BSID-III composite scores. Logistic regression analyses were applied to predict developmental delay vs non-delayed status (cut-off composite score of below 80 for developmental delay) based on the maternal levels of pyrethroid metabolites. In the first, second and third trimesters of pregnancy, the detection rates of pyrethroid metabolites were 94.7%, 90.7%, and 89.0%; the 50th percentiles of exposure level were 0.24 μg/g, 0.24 μg/g and 0.21 μg/g for 3-PBA, 0.14 μg/g, 0.17 μg/g and 0.15 μg/g for 4 F-3PBA, 0.21 μg/g, 0.25 μg/g and 0.19 μg/g for cis-DBCA respectively. In the second trimester, 3-PBA was inversely associated with Cognition and Language scores [β = −3.34 (95% CI = −6.11, −0.57) and β = −2.90 (95% CI = −5.20, −0.61), respectively], and significantly increased the risk of Cognition and Language developmental delay [OR= 1.64 (95% CI = 1.03, 2.62) and OR = 1.52 (95% CI = 1.06, 2.19), respectively]; cis-DBCA was inversely associated with Adaptive Behavior scores [β = −0.73 (95% CI = −1.27, −0.19)], and significantly increased the risk of Adaptive Behavior developmental delay [OR= 1.11 (95% CI = 1.02, 1.21)]. When the maternal levels of pyrethroid metabolites were stratified into the regression models according to the 90th percentile of exposure, in the first trimester, Cognition and Motor scores were inversely associated with higher cis-DBCA [β = −7.19 (95% CI = −12.97, −1.41) and β = −8.20 (95% CI = −13.35, −3.05), respectively], Language scores were inversely associated with higher 3-PBA [β = −6.01 (95% CI = −10.96, −1.06)]; in the second trimester, Cognition scores were inversely associated with higher cis-DBCA [β = −6.64 (95% CI = −12.51, −0.76)], Language scores were inversely associated with higher 3-PBA [β = −5.17 (95% CI = −10.07, −0.27)] and cis-DBCA [β = −5.40 (95% CI = −10.28, −0.52)]. We concluded that pyrethroid exposure in the first and second trimesters was associated with poorer infants neurodevelopmental outcomes at one year of age, and these effects were particularly pronounced at high levels of pyrethroid exposure.

Ambient fine particulate matter air pollution and the risk of preterm birth: A multicenter birth cohort study in China

Preterm birth (PTB), defined as live birth before the 37th week of gestation, is believed to have profound impacts on the infant's health in later life. Air pollution has been suggested to be a potential risk factor of PTB, but the evidence was inconsistent. In this multicenter birth cohort study, we aimed to examine the association between fine particulate matter (PM2.5) exposure during pregnancy and PTB in China. A total of 5976 live births were identified between Jan. 2009 and Feb. 2011 from 8 provinces in China. Residential exposures to PM2.5 were assigned based on satellite remote sensing estimates. Cox proportional hazards regressions were employed to explore the correlation for each trimester as well as the entire pregnancy. A total of 443 (7.4%) preterm births were observed. The average PM2.5 during pregnancy was 57.2 ± 8.8 μg/m3. We found exposure to PM2.5 during the whole pregnancy (hazard ratio, HR = 1.262; 95% CI: 1.087–1.465) and in the first trimester (HR = 1.114; 95% CI: 1.007–1.232) was associated with higher risk of PTB. The associations of PM2.5 were stronger for subjects with older maternal or paternal age, lower maternal pre-pregnancy BMI, and lower family income. This study adds supports to the cumulating evidence linking PM2.5 exposure and elevated PTB risk. Measures of air pollution reduction are needed during pregnancy, especially at early stage of pregnancy to prevent adverse birth outcomes.

Association between Iron Supplementation, Dietary Iron Intake and Risk of Moderate Preterm Birth: A Birth Cohort Study in China.

Background:To evaluate the independent and collective effects of maternal iron supplementation and dietary iron intake upon the risk of moderate preterm birth and its subtypes.Methods:In this birth cohort study, 1019 pregnant women with moderate preterm birth and 9160 women with term birth were recruited at Gansu Provincial Maternity and Child Care Hospital from 2010–2012 in China. Unconditional logistic regression models were utilized to evaluate the association between maternal iron supplementation, dietary iron intake, and the risk of moderate preterm birth and its subtypes.Results:Compared with non-users, iron supplement users exerted a protective effect upon the overall (OR=0.54, 95%CI=0.40–0.72) and spontaneous moderate preterm birth (OR=0.39, 95%CI=0.33–0.83). Compared with the 25th quartiles of dietary iron intake, either before or during pregnancy, it exerted a significantly protective effect upon those who had the highest quartiles of dietary iron intake (OR=0.87, 95%CI=0.82–0.95 for the highest quartiles of dietary iron intake before pregnancy OR=0.85, 95%CI=0.79–0.91). Positive association was observed between the additive scale and multiplicative scale for preterm birth, spontaneous preterm rather than medically indicated preterm.Conclusion:Iron supplements (60 mg/day) and high-iron intake (>25.86 mg/day before pregnancy, >30.46 mg/day during pregnancy) reduced the risk of moderate preterm birth. Positive correlation is found between the additive scale and multiplicative scale for preterm birth, spontaneous preterm birth.

Effects of prenatal exposure to bisphenols on newborn leucocyte telomere length: a prospective birth cohort study in China.

Telomere length (TL) at birth is related to diseases that may arise in the future and long-term health. Bisphenols exhibit toxic effects and can cross the placenta barrier. However, the effects of prenatal exposure to bisphenols on newborn TL remain unknown. We aimed to explore the effects of prenatal exposure to bisphenols (i.e., bisphenol A [BPA], bisphenol B [BPB], bisphenol F [BPF], bisphenol S [BPS] and tetrabromobisphenol A [TBBPA]) on relative TL in newborns. A total of 801 mother-infant pairs were extracted from the Guangxi Zhuang Birth Cohort. The relationship between bisphenol levels in maternal serum and relative TL in cord blood was examined by generalized linear models and restricted cubic spline (RCS) models. After adjusting for confounders, we observed a 3.19% (95% CI: -6.08%, -0.21%; P = 0.037) reduction in relative cord blood TL among mothers ≥ 28 years old, with each onefold increase in BPS. However, in each onefold increase of TBBPA, we observed a 3.31% (95% CI: 0.67%, 6.01%; P = 0.014) increase in relative cord blood TL among mothers < 28 years old. The adjusted RCS models revealed similar results (P overall < 0.05, P non-linear >0.05). This study was the first to establish a positive association between serum TBBPA levels and relative TL in newborns born to young mothers. However, BPS levels were inversely correlated with TL in fetus born to old mothers. The results suggested that the fetus of old pregnant women may be more sensitive to BPS exposure. Moreover, BPS exposure early in life may accelerate aging or increase the risk of developing BPS-related diseases in later life.

The association between maternal exposure to fine particulate matter (PM2.5) and gestational diabetes mellitus (GDM): a prospective birth cohort study in China

Although previous studies have proposed an association between maternal exposure to fine particulate matter (PM2.5) and the risk of gestational diabetes mellitus (GDM), such evidence remains rare. Additionally, the effects of PM2.5 on glycemic control in GDM patients are poorly known. In this study, we conducted a prospective birth cohort study in China, and aimed to investigate the association between maternal exposure to PM2.5 and the risk of GDM, identify the susceptible exposure window, and quantify the exposure-response relationships between PM2.5 and fasting glucose in GDM patients. A spatiotemporal land-use-regression model was used to estimate individual weekly PM2.5 exposure during pregnancy. A distributed lag nonlinear model incorporated with a Cox proportional hazard model was used to estimate the association between maternal exposure to PM2.5 and the risk of GDM. Among the 4174 pregnant women in our study, 1018 (24.4%) were diagnosed with GDM. Each 10 μg m−3 increment in PM2.5 exposures during the 24th gestational week was significantly associated with a higher risk of GDM [hazard ratio (HR) = 1.03, 95% CI (confidence interval): 1.01, 1.06]. Compared to the lowest quartile (Q1) of PM2.5 exposure, participants with the highest quartile (Q4) during the 21st–24th gestational weeks had a higher risk of GDM, and the strongest association was observed in the 22nd gestational week (HR = 1.15, 95%Cl: 1.02, 1.28). The mean PM2.5 exposures during the 21st–24th weeks were positively associated with fasting plasma glucose in pregnant women with GDM. Each 10 μg m−3 increase in the mean PM2.5 exposure was associated with a 0.07 mmol l−1 (95% CI: 0.04, 0.11 mmol l−1) increase in the fasting glucose level. Our findings suggest that maternal exposure to higher PM2.5 during pregnancy may increase the risk of GDM, and result in poor glycemic control among pregnant women with GDM. The 21st–24th gestational week period might be the (most)? susceptible exposure window of PM2.5.

Early childhood screen time as a predictor of emotional and behavioral problems in children at 4\u2009years: a birth cohort study in China

BackgroundPrevious studies have suggested that screen time (ST) has a negative effect on children’s emotional and behavioral health, but there are few longitudinal studies that have been conducted with infants and toddlers. This study sought to examine the effect of ST in early childhood on emotional and behavioral problems in children aged 4 years, based on a birth cohort study in China.MethodsA total of 2492 children aged 4 years were enrolled in this study. The parents and guardians of each child completed a questionnaire that included items eliciting information on children’s birth information, socio-demographic information at baseline, and ST at each follow-up. Emotional and behavioral problems were assessed using the Strengths and Difficulties Questionnaire (SDQ) at 4 years of age. Multivariate logistic analysis was used to explore the effects of ST on emotional and behavioral problems.ResultsThe percentages of children with ST > 0 h/day at age 0.5 years, ST > 2 h/day at age 2.5 years, and ST > 2 h/day at age 4 years were 45.7, 55.5, and 34.5% respectively. The prevalence of emotional and behavioral problems was 10.8%. ST at 6 months was a risk factor for emotional symptoms and hyperactivity at the age of 4 years. ST at age 2.5 years was a risk factor for hyperactivity at the age of 4 years. However, ST at age 4 years was a risk factor for total difficulties, conduct problems, peer problems, hyperactivity, and prosocial behavior.ConclusionsHigher ST exposure at early childhood is associated with later emotional and behavioral problems. In particular, sustained high ST exposure is a risk factor for behavioral problems. These findings suggested the importance of controlling ST to prevent the occurrence of emotional and behavioral problems in the early years.

Association of gestational diabetes mellitus with offspring weight status across infancy: a prospective birth cohort study in China

BackgroundThe association between gestational diabetes mellitus (GDM) and childhood body weight remains controversial, and additional study is needed, especially in Asian populations.MethodsThis prospective study investigated the association between maternal glucose concentration, and GDM status and infant body weight from birth to 12 months of age. Linear mixed effects (LME) models and multiple linear regression were used to assess the longitudinal association of GDM with infant growth measured by weight-for-length z-scores (WFLZ), weight-for-age z-scores (WFAZ), and length-for-age z-scores (LFAZ) at birth, 1, 3, 6, 8, and 12 months of age.ResultsOffspring born to mothers with GDM had higher WFLZ [β: 0.26 SD units (95% CI: 0.13–0.40)] across infancy than those of mothers without GDM. When stratified analysis by maternal pre-pregnancy body mass index (BMI) status, the association was pronounced in normal-weight [β:0.28 SD units (95% CI: 0.11–0.45)] and overweight/obese women [β: 0.34 SD units (95% CI: 0.09–0.58)] but not in underweight women (P for interaction < 0.05). Multiple linear regression found that the effect estimate of GDM on infant WFLZ was highest at birth [β: 0.36 SD units (95% CI: 0.11–0.61)], remained significant at 1 [β: 0.22 SD units (95% CI: 0.03–0.41)] and 3 [β:0.19 SD units (95% CI: 0.01–0.37)] months of age and decreased across infancy. Maternal GDM status was not associated with infant WFAZ or LFAZ.ConclusionsMaternal GDM status was associated with infant WFLZ, but not WFAZ or LFAZ. The association between GDM status and offspring WFLZ was more pronounced in early infancy or in normal-weight and overweight/obese women. Increased public health efforts to prevent GDM in normal-weight and overweight/obese pre-pregnancy mothers are recommended to control offspring overweight or obesity.

Folic Acid Supplementation and the Association between Maternal Airborne Particulate Matter Exposure and Preterm Delivery: A National Birth Cohort Study in China.

Background:Potential modification of the association between maternal particulate matter (PM) exposure and preterm delivery (PTD) by folic acid (FA) supplementation has not been studied.Objective:We examined whether FA supplementation could reduce the risk of PTD associated with maternal exposure to PM in ambient air during pregnancy.Method:In a cohort study covering 30 of the 31 provinces of mainland China in 2014, 1,229,556 primiparas of Han ethnicity were followed until labor. We collected information on their FA supplementation and pregnancy outcomes and estimated each participant’s exposure to PM with diameters of (), (), and () using satellite remote-sensing based models. Cox proportional hazard regression models were used to examine interactions between FA supplementation and PM exposures, after controlling for individual characteristics.Results:Participants who initiated FA prior to pregnancy (38.1%) had a 23% [hazard ratio (95% CI: 0.76, 0.78)] lower risk of PTD than women who did not use preconception FA. Participants with PM concentrations in the highest quartile had a higher risk of PTD [ (95% CI: 1.26, 1.32) for , 1.52 (95% CI: 1.46, 1.58) for , and 1.22 (95% CI: 1.17, 1.27) for ] than those with exposures in the lowest PM quartiles. Estimated associations with a increase in and were significantly lower among women who initiated FA prior to pregnancy [ (95% CI: 1.08, 1.10) for both exposures] than among women who did not use preconception FA [ (95% CI: 1.11, 1.13) for both exposures; ]. The corresponding association was also significantly lower for a increase in [ (95% CI: 1.02, 1.03) for FA before pregnancy vs. 1.04 (95% CI: 1.03, 1.04) for no preconception FA; ].Conclusion:Our findings require confirmation in other populations, but they suggest that initiating FA supplementation prior to pregnancy may lessen the risk of PTD associated with PM exposure during pregnancy among primiparas of Han ethnicity. https://doi.org/10.1289/EHP6386