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BACKGROUND: Gestational per- and polyfluoroalkyl substances (PFAS) exposure may be associated with adiposity and increased risk of obesity among children and adolescents. However, results from epidemiological studies evaluating these associations are inconsistent. OBJECTIVES: We estimated the associations of pregnancy PFAS concentrations with child body mass index (BMI) z-scores and risk of overweight/ obesity in eight U.S. cohorts. METHODS: We used data from 1,391 mother–child pairs who enrolled in eight Environmental influences on Child Health Outcomes (ECHO) cohorts (enrolled: 1999–2019). We quantified concentrations of seven PFAS in maternal plasma or serum in pregnancy. We measured child weight and height between the ages of 2 and 5 y and calculated age- and sex-specific BMI 풵-scores; 19.6% children had more than one BMI measurement. We estimated covariate-adjusted associations of individual PFAS and their mixture with child BMI 풵-scores and risk of overweight/obesity using linear mixed models, modified Poisson regression models, and Bayesian approaches for mixtures. We explored whether child sex modified these associations. RESULTS: We observed a pattern of subtle positive associations of PFAS concentrations in pregnancy with BMI 풵-scores and risk of overweight/obesity. For instance, each doubling in perfluorohexane sulfonic acid concentrations was associated with higher BMI 풵-scores (β=0.07; 95% CI: 0.01, 0.12). Each doubling in perfluroundecanoic acid [relative risk (RR)=1.10; 95% CI: 1.04, 1.16] and 푁-methyl perfluorooctane sulfonamido acetic acid (RR=1.06; 95% CI: 1.00, 1.12) was associated with increased risk of overweight/obesity, with some evidence of a monotonic dose–response relation. We observed weaker and more imprecise associations of the PFAS mixture with BMI or risk of overweight/obesity. Associations did not differ by child sex. DISCUSSION: In eight U.S.-based prospective cohorts, gestational exposure to higher levels of PFAS were associated with slightly higher childhood BMI 풵-score and risk of overweight or obesity. Future studies should examine associations of gestational exposure to PFAS with adiposity and related cardiometabolic consequences in older children. [ABSTRACT FROM AUTHOR]

BACKGROUND: The National Institutes of Health’s Environmental influences on Child Health Outcomes (ECHO) initiative aims to understand the impact of environmental factors on childhood disease. Over 40,000 chemicals are approved for commercial use. The challenge is to prioritize chemicals for biomonitoring that may present health risk concerns. OBJECTIVES: Our aim was to prioritize chemicals that may elicit child health effects of interest to ECHO but that have not been biomonitored nationwide and to identify gaps needing additional research. METHODS: We searched databases and the literature for chemicals in environmental media and in consumer products that were potentially toxic. We selected chemicals that were not measured in the National Health and Nutrition Examination Survey. From over 700 chemicals, we chose 155 chemicals and created eight chemical panels. For each chemical, we compiled biomonitoring and toxicity data, U.S. Environmental Protection Agency exposure predictions, and annual production usage. We also applied predictive modeling to estimate toxicity. Using these data, we recommended chemicals either for biomonitoring, to be deferred pending additional data, or as low priority for biomonitoring. RESULTS: For the 155 chemicals, 97 were measured in food or water, 67 in air or house dust, and 52 in biospecimens. We found in vivo endocrine, developmental, reproductive, and neurotoxic effects for 61, 74, 47, and 32 chemicals, respectively. Eighty-six had data from high-throughput in vitro assays. Positive results for endocrine, developmental, neurotoxicity, and obesity were observed for 32, 11, 35, and 60 chemicals, respectively. Predictive modeling results suggested 90% are toxicants. Biomarkers were reported for 76 chemicals. Thirty-six were recommended for biomonitoring, 108 deferred pending additional research, and 11 as low priority for biomonitoring. DISCUSSION: The 108 deferred chemicals included those lacking biomonitoring methods or toxicity data, representing an opportunity for future research. Our evaluation was, in general, limited by the large number of unmeasured or untested chemicals. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To examine racial/ethnic disparities in the prevalence of diabetes and prediabetes by BMI category. RESEARCH DESIGN AND METHODS: In a consortium of three U.S. integrated health care systems, 4,906,238 individuals aged ‡20 years during 2012–2013 were included. Diabetes and prediabetes were ascertained by diagnosis and laboratory results; antihyperglycemic medications were also included for diabetes ascertainment. RESULTS: The age-standardized diabetes and prediabetes prevalence estimates were 15.9% and 33.4%, respectively. Diabetes but not prediabetes prevalence increased across BMI categories among all racial/ethnic groups (P for trend < 0.001). Racial/ethnic minorities reached a given diabetes prevalence at lower BMIs than whites; Hawaiians/Pacific Islanders and Asians had a diabetes prevalence of 24.6% (95% CI 24.1–25.2%) in overweight and 26.5% (26.3–26.8%) in obese class 1, whereas whites had a prevalence of 23.7% (23.5–23.8%) in obese class 2. The age-standardized prediabetes prevalence estimates in overweight among Hispanics (35.6% [35.4–35.7%]), Asians (38.1% [38.0–38.3%]), and Hawaiians/Pacific Islanders (37.5% [36.9–38.2%]) were similar to those in obese class 4 among whites (35.3% [34.5–36.0%]), blacks (36.8% [35.5–38.2%]), and American Indians/Alaskan Natives (34.2% [29.6–38.8%]). In adjusted models, the strength of association between BMI and diabetes was highest among whites (relative risk comparing obese class 4 with normal weight 7.64 [95% CI 7.50–7.79]) and lowest among blacks (3.16 [3.05–3.27]). The association between BMI and prediabetes was less pronounced. CONCLUSIONS: Racial/ethnic minorities had a higher burden of diabetes and prediabetes at lower BMIs than whites, suggesting the role of factors other than obesity in racial/ethnic disparities in diabetes and prediabetes risk and highlighting the need for tailored screening and prevention strategies. [ABSTRACT FROM AUTHOR]

Objective Food insecurity is positively associated with asthma, the most common chronic childhood disease, yet directionality is unclear. The objective was to determine the association between exposure to food insecurity in early childhood and the odds of asthma later in childhood. Design Data from four waves of the Early Childhood Longitudinal Study-Kindergarten (ECLS-K) cohort, a prospective, dual-frame, multistage probability cluster sampling study of school-aged US children were entered in multivariate logistic regression models, adjusted for covariates. Exposures to food insecurity were based on parental responses to the validated USDA 18-item module at each wave. Setting Public and private primary and secondary schools between 1998 and 2007. Participants At its inception (1999), the ECLS-K had 20 578 kindergarteners; by the spring of eighth grade (2007), the cohort dropped to 9725 due to attrition. Children missing an exposure, outcome or confounding variable were excluded, final n=6731. Primary outcome measure Child's diagnosis of asthma by a healthcare professional as reported by the parent. Results Household food insecurity (vs food security) in the year before kindergarten and in second grade had a higher odds of asthma by 18% (95% CI 1.17 to 1.20) and 55% (95% CI 1.51 to 1.55). After removing asthmatics before third grade from the model, food insecurity in second grade was associated with higher odds of asthma at fifth or eighth grades (OR 1.55; 95% CI 1.53 to 1.58), whereas food insecurity in the year before kindergarten had a lower odds at fifth or eighth grades. Conclusions Food insecurity in the year before kindergarten and in second grade were associated with a higher odds of asthma in third grade. Food insecurity in second grade retained the signal for increased odds of asthma after third and through eighth grades. Additional research is needed to explore childhood windows of vulnerability to asthma. [ABSTRACT FROM AUTHOR]

Objective: Evaluate whether a tailored letter improved gestational weight gain (GWG) and whether GWG mediated a multicomponent intervention's effect on postpartum weight retention among women with gestational diabetes mellitus (GDM).Research Design and Methods: A cluster-randomized controlled trial of 44 medical facilities (n = 2,014 women) randomized to usual care or a multicomponent lifestyle intervention delivered during pregnancy (tailored letter) and postpartum (13 telephone sessions) to reduce postpartum weight retention. The tailored letter, using electronic health record (EHR) data, recommended an end-of-pregnancy weight goal tailored to prepregnancy BMI and GWG trajectory at GDM diagnosis: total GWG at the lower limit of the IOM range if BMI ≥18.5 kg/m2 or the midpoint if <18.5 kg/m2 and weight maintenance if women had exceeded this. The outcomes for this study were the proportion of women meeting the Institute of Medicine (IOM) guidelines for weekly rate of GWG from GDM diagnosis to delivery and meeting the end-of-pregnancy weight goal.Results: The tailored letter significantly increased the proportion of women meeting the IOM guidelines (72.6% vs. 67.1%; relative risk 1.08 [95% CI 1.01-1.17]); results were similar among women with BMI <25.0 kg/m2 (1.07 [1.00-1.15]) and ≥25.0 kg/m2 (1.08 [0.98-1.18]). Thirty-six percent in the intervention vs. 33.0% in usual care met the end-of-pregnancy weight goal (1.08 [0.99-1.18]); the difference was statistically significant among women with BMI <25.0 kg/m2 (1.28 [1.05-1.57]) but not ≥25.0 kg/m2 (0.99 [0.87-1.13]). Meeting the IOM guidelines mediated the effect of the multicomponent intervention in reducing postpartum weight retention by 24.6% (11.3-37.8%).Conclusions: A tailored EHR-based letter improved GWG, which mediated the effect of a multicomponent intervention in reducing postpartum weight retention. [ABSTRACT FROM AUTHOR]

Objective: To examine whether gestational diabetes mellitus (GDM), independent of subsequent diabetes, is an early risk factor for renal impairment long term after the index pregnancy.Research Design and Methods: In the Diabetes & Women's Health (DWH) study (2012-2016), we examined the independent and joint associations of GDM and subsequent diabetes with long-term renal function among 607 women with and 619 women without GDM in the Danish National Birth Cohort (DNBC) index pregnancy (1996-2002). At median follow-up of 13 years after the index pregnancy, serum creatinine (mg/dL) and urinary albumin (mg/L) and creatinine (mg/dL) were measured, from which estimated glomerular filtration rate (eGFR) (mL/min/1.73 m2) and urinary albumin-to-creatinine ratio (UACR) (mg/g) were derived.Results: Compared with women without GDM or subsequent diabetes, women with a GDM history had significantly higher eGFR even if they had not subsequently developed diabetes (adjusted β-coefficient [95% CI] = 3.3 [1.7, 5.0]). Women who had a GDM history and later developed diabetes (n = 183) also had significantly higher UACR [exponent β = 1.3 [95% CI 1.1, 1.6]) and an increased risk of elevated UACR (≥20 mg/g) [adjusted relative risk [95% CI] = 2.3 [1.1, 5.9]) compared with women with neither. After adjusting for potential confounders including prepregnancy BMI and hypertension, GDM without subsequent diabetes was not related to UACR.Conclusions: Women who develop GDM in pregnancy were more likely to show increased eGFR levels 9-16 years postpartum, which could indicate early stages of glomerular hyperfiltration and renal damage. However, only those who subsequently developed diabetes showed overt renal damage as evidenced by elevated UACR. [ABSTRACT FROM AUTHOR]

Background: Animal data suggest sexually dimorphic programming of obesity in response to altered intrauterine environment, but the longitudinal impact of gestational diabetes mellitus (GDM) on sex-specific risk of offspring obesity in humans is unclear.Methods: We conducted a prospective analysis of 15 009 US individuals (7946 female and 7063 male) from the Growing-Up Today Study, who were followed from 1996 (ages 9-14 years) through 2010. Height and weight from validated questionnaires were used to derive body mass index (BMI) at different ages. Obesity during childhood (< 18 years) and adulthood (≥ 18 years) were defined using the International Obesity Task Force and the World Health Organization criteria. GDM exposure was identified through self-reported questionnaires from mothers. Relative risks were estimated using multivariable log-binomial regression models with generalized estimating equations accounting for clustering within the same family.Results: Male offspring born from pregnancies complicated by GDM had higher BMI compared with non-GDM offspring and had increased risk of obesity; the adjusted relative risk [RR, 95% confidence interval (CI)] was 1.47 (1.11-1.95) for all age groups, 1.59 (1.05-2.41) for late childhood, 1.48 (1.06-2.06) for adolescence and 1.39 (1.00-1.94) for early adulthood. No significant association between obesity and maternal GDM was observed among female participants (RR = 0.97, 95% CI: 0.71-1.33).Conclusions: The association of GDM with offspring obesity from late childhood through early adulthood may differ by sex; a significant association was observed among male but not female offspring. [ABSTRACT FROM AUTHOR]

Background: Artificial sweeteners are widely replacing caloric sweeteners. Data on long-term impact of artificially sweetened beverage (ASB) consumption during pregnancy on offspring obesity risk are lacking. We prospectively investigated intake of ASBs and sugar-sweetened beverages (SSBs) during pregnancy in relation to offspring growth through age 7 years among high-risk children born to women with gestational diabetes.Methods: In a prospective study of 918 mother-singleton child dyads from the Danish National Birth Cohort, maternal dietary intake was assessed by a food frequency questionnaire during pregnancy. Offspring body mass index z-scores (BMIZ) and overweight/obesity status were derived using weight and length/height at birth, 5 and 12 months and 7 years. Linear regression and Poisson regression with robust standard errors were used, adjusting for major risk factors.Results: Approximately half of women reported consuming ASBs during pregnancy and 9% consumed daily. Compared to never consumption, daily ASB intake during pregnancy was positively associated with offspring large-for-gestational age [adjusted relative risk (aRR) 1.57; 95% CI: 1.05, 2.35 at birth], BMIZ (adjusted β 0.59; 95% CI: 0.23, 0.96) and overweight/obesity (aRR 1.93; 95% CI; 1.24, 3.01) at 7 years. Per-serving-per-day substitution of ASBs with water during pregnancy was related to a lower overweight/obesity risk at 7 years (aRR 0.83; 95% CI: 0.76, 0.91), whereas SSB substitution with ASBs was not related to a lower risk (aRR 1.14; 95% CI: 1.00, 1.31).Conclusions: Our findings illustrated positive associations between intrauterine exposure to ASBs and birth size and risk of overweight/obesity at 7 years. Data with longer follow-up are warranted. [ABSTRACT FROM AUTHOR]

Air pollution has been linked to hypertension in the general population, but data on gestational hypertension (GH) are limited. We investigated criteria air pollutants and air toxics during the period before conception and in early gestation in relation to GH risk in the Consortium on Safe Labor/Air Quality and Reproductive Health Study (United States, 2002-2008). Modified Community Multi-scale Air Quality models estimated air pollution exposures for 6,074 singleton pregnancies in which GH was present and 199,980 normotensive pregnancies. Generalized estimating equations estimated relative risks per interquartile-range increment for pollutants and high exposure (≥75th percentile) for air toxics after adjustment for major risk factors. For an interquartile-range increment, GH risk was significantly increased by 18% for sulfur dioxide during the 3 months before conception and, during gestational weeks 1-20, 17% for nitrogen oxides, 10% for particulate matter with an aerodynamic diameter <2.5 µm, 7% for particulate matter with an aerodynamic diameter <10 µm, and 22% for sulfur dioxide. High exposures to several polycyclic aromatic hydrocarbons before conception and during the first trimester were significantly associated with 8%-20% higher risk of GH. Further, preconceptional exposures to several volatile organic compounds were significantly associated with 11%-19% higher risk. Our findings suggest that early exposures to criteria air pollutants, particularly from transport emissions, and high exposure to several air toxics before conception may increase GH risk. [ABSTRACT FROM AUTHOR]

Background: Refined grains, a major source of dietary carbohydrates, have been related to impaired glucose homeostasis and obesity. Emerging animal data suggest that in utero exposure to dietary refined carbohydrates may predispose offspring to an obese phenotype, indicating a potential role for nutritional programming in the early origins of obesity, but intergenerational human data are lacking. Objective: We prospectively investigated refined-grain intake during pregnancy in association with offspring growth through age 7 y among high-risk children born to women with gestational diabetes mellitus (GDM). Design: The analysis included 918 mother-singleton child dyads from the Danish National Birth Cohort. Offspring body mass index z scores (BMIZs) were calculated by using weight and length or height measured at birth, 5 and 12 mo, and 7 y. Overweight or obesity was defined by WHO cutoffs. Linear and Poisson regressions were used, with adjustment for maternal demographic, lifestyle, and dietary factors. Results: Refined-grain intake during pregnancy was positively associated with offspring BMIZ (adjusted β per serving increase per day: 0.09; 95% CI: 0.02, 0.15) and risk of overweight or obesity at age 7 y [adjusted RR (aRR) comparing the highest with the lowest quartile: 1.80; 95% CI: 1.09, 2.98; P-trend = 0.032]. The association appeared to be more pronounced among children who were breastfed <6 mo. The substitution of 1 serving refined grains/d with an equal serving of whole grains during pregnancy was related to a 10% reduced risk of offspring overweight or obesity at 7 y of age (aRR: 0.90; 95% CI: 0.82, 0.98). No associations were observed between refined-grain intake and infant growth. Conclusions: Higher maternal refined-grain intake during pregnancy was significantly related to a greater BMIZ and a higher risk of overweight or obesity at age 7 y among children born after pregnancies complicated by GDM. The findings highlight pregnancy as a potential window of susceptibility associated with off-spring growth and obesity risk among this high-risk population. Data with longer follow-up are warranted. [ABSTRACT FROM AUTHOR]

BACKGROUND: Climate change is expected to have adverse health effects, but the association between extreme ambient temperatures and stillbirth is unclear. OBJECTIVES: We investigated acute and chronic associations between extreme ambient temperatures and stillbirth risk, and estimated the attributable risk associated with local temperature extremes in the United States. METHODS: We linked 223,375 singleton births ≥23 weeks of gestation (2002-2008) from 12 U.S. sites to local temperature. Chronic exposure to hot (>90th percentile), cold (<10th percentile), or mild (10th-90th percentile) temperatures was defined using window- and site-specific temperature distributions for three-months preconception, first and second trimester, and whole-pregnancy averages. For acute exposure, average temperature for the week preceding delivery was compared to two alternative control weeks in a case-crossover analysis. RESULTS: In comparison with mild, whole-pregnancy exposure to cold [adjusted odds ratio (aOR) = 4.75; 95% confidence interval (CI): 3.95, 5.71] and hot (aOR = 3.71; 95% CI: 3.07, 4.47) were associated with stillbirth risk, and preconception and first and second trimester exposures were not. Approximately 17-19% of stillbirth cases were potentially attributable to chronic whole-pregnancy exposures to local temperature extremes. This is equivalent to ∼1,116 cold-related and ∼1,019 hot-related excess cases in the United States annually. In the case-crossover analysis, a 1°C increase during the week preceding delivery was associated with a 6% (3-9%) increase in stillbirth risk during the warm season (May-September). This incidence translates to ∼4 (2-6) additional stillbirths per 10,000 births for each 1°C increase. CONCLUSIONS: Extremes of local ambient temperature may have chronic and acute effects on stillbirth risk, even in temperate zones. Temperature-related effects on pregnancy outcomes merit additional investigation. [ABSTRACT FROM AUTHOR]

Background: Increasing recognition has been received regarding the proven and suggested links between multi-level environmental exposures on a broad scale (e.g., chemical, clinical, behavioral, physical and social) and health deficits originated from the critical window of development. However, such prospective human data are limited. In 2016, the National Institutes of Health funded 35 centers comprising 84 extant cohorts for the Environmental Influences on Child Health Outcomes (ECHO) pediatric cohorts program. The Pregnancy Environment and Lifestyle Study (PETALS) is one of the cohorts at the participating centers of Kaiser Permanente Northern California (KPNC).Methods: PETALS was originally funded by the National Institute of Environmental Health Sciences to establish a longitudinal birth cohort of 3,350 mother-infant pairs and conduct a nested case-control study of 300 women with gestational diabetes (GDM) and 600 matched controls to investigate the associations between phenol exposures in first and second trimesters and GDM risk and the related outcome of infant macrosomia. This paper describes the prospective cohort design of PETALS, current research activities, and cohort profile of enrolled women who delivered as of February 2016. Women are enrolled from the KPNC membership. Fasting blood draw, urine collection, anthropometric measurements, and questionnaires on health history and lifestyle are completed at baseline and follow-up clinic visits with targeted windows of 10-13 and 16-19 weeks of gestation, respectively. Further, women's clinical and health assessments before and after the index pregnancy in addition to their children's birth outcomes and health information can be abstracted from electronic health records, allowing future follow-up. Study data could also be linked and extended to a myriad of additional observational data including environmental and area-level databases and census data.Discussion: In this racially- and ethnically-diverse pregnancy cohort, the generated biospecimen and data repository will establish a comprehensive framework which may provide unique opportunities to address a multitude of research questions on the intrauterine environment and adverse pregnancy and birth outcomes in a representative multi-racial/ethnic population with generalizable findings. [ABSTRACT FROM AUTHOR]

Premature rupture of membranes (PROM) is a major factor that predisposes women to preterm delivery. Results from previous studies have suggested that there are associations between exposure to air pollution and preterm birth, but evidence of a relationship with PROM is sparse. Modified Community Multiscale Air Quality models were used to estimate mean exposures to particulate matter less than 10 um or less than 2.5 um in aerodynamic diameter, nitrogen oxides, carbon monoxide, sulfur dioxide, and ozone among 223,375 singleton deliveries in the Air Quality and Reproductive Health Study (2002-2008). We used log-linear models with generalized estimating equations to estimate adjusted relative risks and 95% confidence intervals for PROM per each interquartile-range increase in pollutants across the whole pregnancy, on the day of delivery, and 5 hours before delivery. Whole-pregnancy exposures to carbon monoxide and sulfur dioxide were associated with an increased risk of PROM (for carbon monoxide, relative risk (RR) = 1.09, 95% confidence interval (CI): 1.04, 1.14; for sulfur dioxide, RR= 1.15, 95% CI: 1.06,1.25) but not preterm PROM. Ozone exposure increased the risk of PROM on the day of delivery (RR = 1.06, 95% CI: 1.02, 1.09) and 1 day prior (RR = 1.04, 95% CI: 1.01, 1.07). In the 5 hours preceding delivery, there were 3%-7% increases in risk associated with exposure to ozone and particulate matter less than 2.5 um in aerodynamic diameter and inverse associations with exposure to carbon monoxide and nitrogen oxides. Acute and long-term air pollutant exposures merit further study in relation to PROM. [ABSTRACT FROM AUTHOR]

Background: Given the long-term adverse sequelae of childhood obesity, identification of early life factors related to fetal growth and childhood obesity is warranted. Investigation on growth and obesity in early life in association with intrauterine exposure to maternal hyperglycemia, a common metabolic pregnancy complication, is of public health significance and clinical implications. Objective: We investigated the association of fasting plasma glucose (FPG) concentrations during pregnancy with offspring growth and risk of overweight/obesity through age 7 y, after adjustment for confounders, including maternal prepregnancy obesity status. Design: FPG concentrations at 28 gestational weeks (IQR: 22-32 wk) were extracted from medical records for 661 pregnancies complicated by gestational diabetes mellitus in the Danish National Birth Cohort (1996-2002). Offspring's ponderal index was derived from birth weight and length; age- and sex-specific body mass index (BMI) z scores at 5 mo, 12 mo, and 7 y were calculated based on WHO reference data. Relations between FPG and offspring growth and obesity were assessed by linear and Poisson regression with robust standard errors, adjusting for maternal prepregnancy BMI and sociodemographic and perinatal factors. Results: At birth, maternal FPG during pregnancy was significantly associated with offspring ponderal index (β = 0.46; 95% CI: 0.14, 0.78 per 1-mmol/L increase) and risk of macrosomia (birth weight >4000 g) (RR = 1.21; 95% CI: 1.07, 1.38 per 1-mmol/L increase). At 7 y, higher maternal FPG concentrations were significantly associated with increased BMI z scores (β = 0.20; 95% CI: 0.04, 0.36) and elevated risk of overweight/obesity (RR = 1.21; 95% CI: 1.01, 1.50). Additional adjustment for birth weight and childhood lifestyle factors did not appreciably alter results. No associations were observed at 5 or 12 mo. Conclusion: Among women with gestational diabetes mellitus, maternal FPG concentrations during pregnancy were significantly and positively associated with offspring birth size and overweight/obesity risk at 7 y, adjusting for maternal prepregnancy BMI. [ABSTRACT FROM AUTHOR]

Objective: Low-carbohydrate diets (LCDs) may improve short-term glycemic control in patients with gestational diabetes mellitus (GDM), but the long-term effect on progression from GDM to type 2 diabetes mellitus (T2DM) is unknown. We aimed to examine the long-term risk of T2DM in association with a low-carbohydrate dietary pattern among women with a history of GDM.Research Design and Methods: Overall, 4,502 women with a history of GDM from the Nurses' Health Study II (NHSII) cohort, as part of the Diabetes & Women's Health (DWH) study, were followed up from 1991 to 2011. Overall, animal, or vegetable LCD scores, which represent adherence to different low-carbohydrate dietary patterns, were calculated using diet intake information assessed every 4 years since 1991 by validated food-frequency questionnaires. We used Cox proportional hazards models to estimate hazard ratios (HRs) and 95% CIs.Results: We documented 722 incident cases of T2DM during 68,897 person-years of observation. The multivariable-adjusted HRs (95% CIs) of T2DM, comparing the highest with lowest quintiles, were 1.36 (1.04-1.78) for overall LCD score (P = 0.003 for trend), 1.40 (1.06-1.84) for animal LCD score (P = 0.004 for trend), and 1.19 (0.91-1.55) for vegetable LCD score (P = 0.50 for trend).Conclusions: Among women with a history of GDM, a low-carbohydrate dietary pattern, particularly with high protein and fat intake mainly from animal-source foods, is associated with higher T2DM risk, whereas a low-carbohydrate dietary pattern with high protein and fat intake from plant-source foods is not significantly associated with risk of T2DM. [ABSTRACT FROM AUTHOR]

Background The relationship between gestational weight gain (GWG) and childhood growth remains controversial. An examination on whether infant feeding practices mediate this relationship may improve our understanding of it. Methods We investigated whether the relationships among GWG, birth weight and childhood anthropometrics were mediated through infant feeding practices (breastfeeding duration and age at introduction of solid foods) in a cross-sectional multiethnic study of 1387 mothers and their children aged 0-5.9 years in the USA (2011-2012). Child anthropometrics included age-specific and sex-specific z-scores for weight-for-age (WAZ), height/length-for-age (HAZ), weight-for-height/length (WHZ) and body mass index-for-age (BMIZ); and ulnar length, a marker for limb growth. We used structural equation modelling to calculate standardised path coefficients and total, direct and indirect associations of GWG, birth weight and infant feeding practices with child anthropometrics. Results Maternal GWG had a positive indirect association with all anthropometrics mediated via birth weight, whereas longer breastfeeding duration reduced the positive associations of GWG and birth weight with WAZ, WHZ and BMIZ in non-Hispanics (β=-0.077, -0.064 and -0.106, respectively). Longer breastfeeding duration and introducing solid foods at a later age were positively associated with ulnar length (β=0.023 and 0.030, respectively) but not HAZ, suggesting a distinct association, for the first time, with limb growth. Conclusions Findings suggest that promoting longer breastfeeding duration among women with excessive GWG who had high birthweight newborns may mitigate the potential for their offspring to develop obesity. In addition, findings reinforce the importance of promoting appropriate GWG and preventing high birth weight, which are positively associated with childhood anthropometrics. [ABSTRACT FROM AUTHOR]

Surrogate measures are needed when recumbent length or height is unobtainable or unreliable. Arm span has been used as a surrogate but is not feasible in children with shoulder or arm contractures. Ulnar length is not usually impaired by joint deformities, yet its utility as a surrogate has not been adequately studied. In this cross-sectional study, we aimed to examine the accuracy and reliability of ulnar length measured by different tools as a surrogate measure of recumbent length and height. Anthropometrics [recumbent length, height, arm span, and ulnar length by caliper (ULC), ruler (ULR), and grid (ULG)] were measured in 1479 healthy infants and children aged <6 y across 8 study centers in the United States. Multivariate mixed-effects linear regression models for recumbent length and height were developed by using ulnar length and arm span as surrogate measures. The agreement between the measured length or height and the predicted values by ULC, ULR, ULG, and arm span were examined by Bland-Altman plots. All 3 measures of ulnar length and arm span were highly correlated with length and height. The degree of precision of prediction equations for length by ULC, ULR, and ULG (R² = 0.95, 0.95, and 0.92, respectively) was comparable with that by arm span (R² = 0.97) using age, sex, and ethnicity as covariates; however, height prediction by ULC (R² = 0.87), ULR (R² = 0.85), and ULG (R² = 0.88) was less comparable with arm span (R² = 0.94). Our study demonstrates that arm span and ULC, ULR, or ULG can serve as accurate and reliable surrogate measures of recumbent length and height in healthy children; however, ULC, ULR, and ULG tend to slightly overestimate length and height in young infants and children. Further testing of ulnar length as a surrogate is warranted in physically impaired or nonambulatory children. [ABSTRACT FROM AUTHOR]

Objective: To examine the association between age at menarche and risk of gestational diabetes mellitus (GDM).Research Design and Methods: A prospective cohort study of 42,109 eligible pregnancies from 27,482 women in the Nurses' Health Study II.Results: The adjusted risk ratios for GDM across the age at menarche categories (≤11, 12, 13, and ≥14 years) were 1.34 (95% CI 1.14-1.58), 1.13 (0.97-1.31), 1.11 (0.95-1.29), and 1.00 (referent; P for trend = 0.0005), respectively. Analysis of the mediating effect indicated that 42.1% (P = 0.0007) of the association was mediated through prepregnancy BMI.Conclusions: These findings suggested that earlier menarche was significantly associated with an increased risk of GDM. This association was largely mediated through prepregnancy excessive body adiposity. [ABSTRACT FROM AUTHOR]