Maternal Covariates Research Articles

Fetal lipidome and incident risk of food allergy: A prospective birth cohort study.

Lipids are proposed to be important in developing adaptive immunity and allergy. However, studies to date reported inconsistent findings. To examine newborn lipidome (a comprehensive profiling of circulating lipid metabolites) on child's risk of developing food allergy (FA). The maternal-cord joint effects of lipid metabolites on FA development were also investigated. This study included 647mother-child pairs from the Boston Birth Cohort and analyzed 202lipid metabolites in cord plasma profiled by liquid chromatography tandem mass spectrometry. FA was defined based on standard clinical criteria. Logistic regression was applied to examine the relationships between individual metabolites and risk of FA. Of the 647 children, 61 developed FA. Cord triacylglycerols of long carbon chains and multiple double bonds were significantly associated with decreased risk of FA. These associations were comparable across strata of pertinent maternal and child covariates, and were independent of maternal triacylglycerols when assessed simultaneously. Besides, cord and maternal triacylglycerols had an additive effect in association with risk of FA: Children having high (≥Median) C56:8 triacylglycerol levels in both cord and maternal plasma were at the lowest risk of developing FA (OR=0.24, 95% CI=0.10-0.56, p=.001), compared to those having low levels in both cord and maternal plasma. This is the first birth cohort study to link altered cord plasma lipidome with future risk of development FA during childhood. It calls for further investigation on triacylglycerols of long carbon chains and multiple double bonds as potential novel predictive biomarkers and therapeutic targets for FA.

An empirical Bayes method for genetic association analysis using case-control mother-child pair data

Case-control mother-child pair data are often used to investigate the effects of maternal and child genetic variants and environmental risk factors on obstetric and early life phenotypes. Retrospective likelihood can fully utilize available information such as Mendelian inheritance and conditional independence between maternal environmental risk factors (covariates) and children’s genotype given maternal genotype, thus effectively improving statistical inference. Such a method is robust to some extent if no relationship assumption is imposed between the maternal genotype and covariates. Statistical efficiency can be considerably improved by assuming independence between maternal genotype and covariates, but false-positive findings would be inflated if the independence assumption was violated. In this study, two empirical Bayes (EB) estimators are derived by appropriately weighting the above retrospective-likelihood-based estimators, which intuitively balance the statistical efficiency and robustness. The asymptotic normality of the two EB estimators is established, which can be used to construct confidence intervals and association tests of genetic effects and gene-environment interactions. Simulations and real-data analyses are conducted to demonstrate the performance of our new method.

Critical Time Windows for Air Pollution Exposure and Birth Weight in a Multicity Canadian Pregnancy Cohort.

Maternal prenatal exposure to air pollution has been associated with adverse birth outcomes. However, previous studies focused on a priori time intervals such as trimesters reported inconsistent associations. We investigated time-varying vulnerability of birth weight to fine particulate matter (PM2.5) and nitrogen dioxide (NO2) using flexible time intervals. We analyzed 1,300 live, full-term births from Maternal-Infant Research on Environmental Chemicals, a Canadian prospective pregnancy cohort spanning 10 cities (2008-2011). Daily PM2.5 and NO2 concentrations were estimated from ground-level monitoring, satellite models, and land-use regression, and assigned to participants from pre-pregnancy through delivery. We developed a flexible two-stage modeling method-using a Bayesian Metropolis-Hastings algorithm and empirical density threshold-to identify time-dependent vulnerability to air pollution without specifying exposure periods a priori. This approach identified critical windows with varying lengths (2-363 days) and critical windows that fell within, or straddled, predetermined time periods (i.e., trimesters). We adjusted the models for detailed infant and maternal covariates. Critical windows associated with reduced birth weight were identified during mid- to late-pregnancy for both PM2.5 and NO2: -6 g (95% credible interval: -11, -1 g) and -5 g (-10, -0.1 g) per µg/m3 PM2.5 during gestational days 91-139 and 249-272, respectively; and -3 g (-5, -1 g) per ppb NO2 during days 55-145. We used a novel, flexible selection method to identify critical windows when maternal exposures to air pollution were associated with decrements in birth weight. Our results suggest that air pollution impacts on fetal development may not be adequately captured by trimester-based analyses.

Associations between T cells and attention problems in the general pediatric population: The Generation R study.

The pathogenesis of attention-deficit/hyperactivity disorder (ADHD) is currently unclear. We hypothesized that chronic immune activation, as indexed by T and B cells, plays a role in the pathophysiology of attention problems. Therefore, we examined T and B cell subsets in a general pediatric population with information on attention problems. We included 756 10-year-old children from the Generation R population-based cohort. Eleven-color flow cytometry was performed on peripheral blood samples to determine T and B cell subsets. The Child Behavior Checklist rated by parents was used to measure attention problems. Data were analyzed using linear regression analyses, adjusting for maternal and child covariates and co-occurring childhood psychopathology. For T helper 1 (Th1) cells, one standard deviation (SD) increase was associated with 5.3% (95%CI 0.3; 10.5) higher attention problem scores. Furthermore, 1SD increase in CD8+ T cells was associated with 7.5% (95%CI 2.4; 12.7) higher attention problem scores. Within total CD8+ T cells, 1SD increase in naive or central memory cells was associated with 6.9% (95%CI 2.0; 12.1) and 6.4% (95%CI 1.5; 11.6) higher attention problem scores, respectively. No associations between Th2, Treg or B memory cells and attention problem scores were observed. Higher Th1 and cytotoxic T cell numbers are associated with higher attention problem scores independent of co-occurring psychopathology. This might indicate a possible role of a pro-inflammatory immune profile in childhood attention problems.

Lactobacillus crispatus thrives in pregnancy hormonal milieu in a Nigerian patient cohort

Steroid hormones are one of the presumed modulators of Lactobacillus abundance in the vaginal epithelium. We set out to characterize the vaginal microbiome (VMB) and also provide an in-depth understanding of the relative contribution of estradiol (E2) and progesterone (P1) in shaping the vaginal microbiome of Nigerian women (n = 38) who experienced both uncomplicated term delivery and preterm delivery using samples longitudinally collected during pregnancy (17–21, 27–31, 36–41 weeks gestation) and 6 weeks postpartum. Vaginal swabs and blood samples were aseptically collected. Vaginal swabs were used for microbiome assessment using 16S ribosomal RNA (rRNA) gene sequencing. Blood samples were used for hormonal measurement using a competitive-based enzyme-linked immunosorbent assay (ELISA). Across several maternal covariates, maternal age, pregnancy status and delivery mode were not significantly associated with the vaginal microbiota whereas maternal E2 level (pE2 = 0.006, Omnibus), and P1 level (pP1 = 0.001, Omnibus) were significantly associated with the vaginal microbiome. E2 and P1 concentrations increased throughout pregnancy commensurately with increasing proportions of L. crispatus (pE2 = 0.036, pP1 = 0.034, Linear Mixed Model). An increasing trend of α-diversity was also observed as pregnancy progressed (pobserved ASV = 0.006, LMM). A compositional microbiome shift from Lactobacillus profile to non-Lactobacillus profile was observed in most postnatal women (pCST IV < 0.001, LMM). Analysis of our data shows a species-specific link between pregnancy steroid hormone concentration and L. crispatus abundance.

Association between prenatal exposure to air pollutants and newborn thyroxine (T4) levels

BACKGROUND AND AIM: Thyroid hormones play a key role in fetal and child development. Recent studies have linked prenatal exposure to atmospheric contaminants with changes in thyroid hormone levels in newborns, but the data from the few studies that have explored this issue are inconclusive. The present study aims to assess the association of total thyroxine (TT4) levels in newborns with weekly prenatal exposure to PM2.5 and NO2 and to identify sensitivity windows to exposure to air pollution in different developmental stages. METHODS: This prospective cohort study included 463 mother-child pairs from the INMA-Gipuzkoa project with data on PM2.5 and NO2 exposure and TT4 levels at birth. PM2.5 and NO2 levels were measured by high-volume aerosol samplers and passive samplers respectively during the women’s pregnancies. TT4 levels were measured in heel-prick blood samples from infants. Data on maternal and infant covariates were gathered through questionnaires administered in the first and third trimesters of pregnancy and review of clinical records. Potential associations of PM2.5 and NO2 with TT4 levels over the entire pregnancy was assessed by linear regression models and DLMs were used to identify susceptibility windows. RESULTS:PM2.5 exposure during pregnancy was positively associated with infant TT4 level at birth (β [95% CI]= 0.198 [0.091, 0.305]. DLMs identified three different sensitivity windows, one in the periconceptional period with a negative association between PM2.5 exposure and TT4 levels at birth, and a second (weeks 12-17) and a third one (weeks 31-37) with a positive association. In addition, the later the exposure, the stronger the association. In contrast, no association was observed between NO2 exposure and TT4 levels. CONCLUSIONS:The results indicate that prenatal exposure to PM2.5 could lead to a thyroid function impairment in newborns. Further, they suggest that the effect of PM2.5 could be partially mediated by maternal thyroid function. KEYWORDS: Prenatal exposure, PM2.5, NO2, TT4 at birth, sensitivity windows

Socio-economic inequality in anthropometric failure among children aged under 5\u2009years in India: evidence from the Comprehensive National Nutrition Survey 2016\u201318

BackgroundConventional indicators used to access the nutritional status of children tend to underestimate the overall undernutrition in the presence of multiple anthropometric failures. Further, factors contributing to the rich-poor gap in the composite index of anthropometric failure (CIAF) have not been explored. This study aims to estimate the prevalence of CIAF and quantify the contribution of factors that explain the rich-poor gap in CIAF.MethodsThe present study used data of 38,060 children under the age of five years and their biological mothers, drawn from the nationally representative Comprehensive National Nutrition Survey of children and adolescents aged 0–19 years in India. The CIAF outcome variable in this study provide an overall prevalence of undernutrition, with six mutually exclusive anthropometric measurements of height-for-age, height-for-weight, and weight-for-age, calculated using the World Health Organization (WHO) Multicenter Growth Reference Study. Multivariate regression and decomposition analysis were used to examine the association between covariates with CIAF and to estimate the contribution of different covariates in the existing rich-poor gap.ResultsAn overall CIAF prevalence of 48.2% among children aged aged under 5 years of age was found in this study. 6.0% children had all three forms of anthropometric failures. The odds of CIAF were more likely among children belonging to poorest households (AOR: 2.41, 95% CI: 2.12–2.75) and those residing in urban area (AOR: 1.06, 95% CI 1.00–1.11). Children of underweight mothers and those with high parity were at higher risk of CIAF (AOR: 1.51, 95% CI: 1.42–1.61) and (AOR: 1.15, 95% CI: 1.08–1.22), respectively. Children of mother exposed to mass media were at lower risk of CIAF (AOR: 0.87, 95% CI: 0.81–0.93).ConclusionThis study estimated a composite index to assess the overall anthropometric failure, which also provides a broader understanding of the extent and pattern of undernutrition among children. Findings show that maternal covariates contribute the most to the rich-poor gap. As well, the findings suggest that intervention programs with a targeted approach are crucial to reach the most vulnerable groups and to reduce the overall burden of undernutrition.

A Prospective Study of Prenatal Maternal Dietary Patterns and Offspring Adipokine Levels During Adolescence

ObjectivesMaternal diet during pregnancy has been associated with offspring adipokine levels related to insulin resistance and hyperlipidemia during infancy. However, whether this relationship persists into adolescence is unknown. We examined the association between maternal prenatal diet patterns with adolescent leptin and adiponectin levels a Mexico City cohort. MethodsData from 379 mother-adolescent dyads from the Mexico City ELEMENT cohort were analyzed. Diet patterns were derived from principal component analysis of food frequency questionnaire data collected during pregnancy trimesters. Adolescent serum leptin and adiponectin were measured at ages 10–17. Information on maternal covariates was measured during pregnancy. Multiple linear regression was used to examine overall and sex-stratified associations between quartiles of diet patterns with leptin and adiponectin, adjusting for maternal marital status, education, and parity. ResultsThree maternal diet patterns were identified: Prudent Diet (PD), high in fish and vegetables, the High Meat & Fat Diet (HMFD), high in pork and processed meats, and the Transitioning Diet (TD), high in corn tortillas and sugar beverages. At follow-up, the mean (SD) of leptin and adiponectin were 24.3 (18.2) ng/ml and 11.7 (3.9) ng/ml. A significant positive association was demonstrated between first trimester TD scores and adipokines in girls. In a multivariate-adjusted model, compared to girls in the lowest quartile (Q1) of the TD pattern, the highest quartile of the TD pattern (Q4) had 10.39 ng/mL higher leptin (95% CI: 3.1, 17.6; p for trend = 0.0024). In addition, compared to girls in the lowest quartile (Q1) of the TD pattern, those in the third quartile (Q3) of the TD pattern had 1.86 ng/mL lower adiponectin (95% CI: –3.5, –0.2; p for trend = 0.168). Associations were mostly consistent across all trimesters. ConclusionsDuring pregnancy, a Transitioning Diet pattern was positively associated with leptin and non-monotonically inversely associated with adiponectin in females. Findings suggest maternal diet patterns during pregnancy may influence offspring leptin and adiponectin levels in adolescent girls. Funding SourcesFunded by grant P01ES022844.

Association between prenatal exposure to air pollutants and newborn thyroxine (T4) levels

Background: Thyroid hormones play a key role in fetal and child development. Recent studies have linked prenatal exposure to atmospheric contaminants with changes in thyroid hormone levels in newborns, but the data from the few studies that have explored this issue are inconclusive. The present study aims to assess the association of total thyroxine (TT4) levels in newborns with weekly prenatal exposure to PM2.5 and NO2 and to identify sensitivity windows to exposure to air pollution in different developmental stages. Methods: This prospective cohort study included mother-child pairs from the INMA-Gipuzkoa project. Specifically, 463 mother-child pairs with data on PM2.5 and NO2 exposure during pregnancy and TT4 levels at birth were included. PM2.5 and NO2 levels were measured by high-volume aerosol samplers and passive samplers respectively during the women's pregnancies. TT4 levels were measured in heel-prick blood samples from infants. Data on maternal and infant covariates were gathered through questionnaires administered in the first and third trimesters of pregnancy and review of clinical records. Potential associations of PM2.5 and NO2 with TT4 levels over the entire pregnancy was assessed by linear regression models and DLMs were used to identify susceptibility windows. Results: The exposure of pregnant women to PM2.5 during pregnancy was positively associated with infant TT4 level at birth (β [95% CI] = 0.198 [0.091, 0.305]. DLMs identified three different sensitivity windows, one in the periconceptional period with a negative association between PM2.5 exposure and TT4 levels at birth, and a second (weeks 12–17) and a third one (weeks 31–37) with a positive association. In addition, the later the exposure, the stronger the association. In contrast, no association was observed between NO2 exposure and TT4 levels. Conclusions: The results indicate that prenatal exposure to PM2.5 could lead to a thyroid function impairment in newborns.

Protein Intake During Infancy and Subsequent Body Mass Index in Early Childhood: Results from the Melbourne InFANT Program

BackgroundThe link between high protein intake during infancy and obesity later in childhood has been much debated, and the association with differing protein sources remains unclear. ObjectiveThis study aimed to examine the associations between total protein intake and protein from different sources (ie, nondairy animal, dairy, and plant) reported at age 9 months and development in body mass index (BMI) z scores until age 5 years. DesignThis study involved a secondary data analysis of the Melbourne InFANT (Infant Feeding, Activity and Nutrition Trial) program, an observational prospective cohort study that was conducted from 2008 to 2013. Participants/settingParticipants were children (n = 345) who completed both the 9-month and 5-year follow-up visits within the Melbourne InFANT program. Main outcome measuresBMI z score was measured at age 5 years. Statistical analyses performedLinear mixed models with a random effect for clusters of mother’s group and with adjustment for baseline child and maternal covariates were conducted. ResultsWith adjustment for covariates, every 1 g or 1% energy increase in total protein intake at age 9 months was associated with a 0.016-unit (95% CI 0.003 to 0.029) or 0.034-unit (95% CI 0.005 to 0.063) increase in BMI z score at age 5 years, respectively. With respect to protein sources, associations of similar magnitude were found for nondairy animal protein. No evidence of an association with BMI z score was found for dairy (including milk, yogurt, cheese, breast milk, and infant formula) and plant proteins. ConclusionsHigh intakes of total protein, nondairy animal protein, but not dairy or plant proteins, during infancy were associated with higher BMI z score in early childhood. These findings can inform dietary recommendations regarding protein intakes during infancy. Clinical trial registrationThe InFANT program was registered with Current Controlled Trials (ISRCTN81847050); http://www.isrctn.com/ISRCTN81847050.

Using a Microsimulation of Energy Balance to Explore the Influence of Prenatal Sugar-Sweetened Beverage Intake on Child BMI.

Experiments with animals suggest that high sugar consumption during pregnancy may predispose offspring to obesity, but few human studies have examined this relationship. This study explored the association between the consumption of sugar-sweetened beverages (SSBs) during pregnancy and caloric intake through childhood. Using cohort data on child weight, height, and physical activity levels, a lab-validated microsimulation model of energy balance was employed to infer the caloric intake of children through age 11 years. Random effects models were then employed to explore the relationships between prenatal maternal consumption and inferred caloric intake during childhood. An additional daily serving of SSBs during the second trimester of pregnancy was associated with an increase in child consumption of 13 kcal/d (95% CI: 1.2-26.8). Age-stratified models adjusting for maternal and child covariates suggested that this association was strongest for children aged 2.5 to 5.5 years. The consumption of SSBs during the first trimester was not found to have a consistently positive relationship to caloric intake. These findings suggest that SSB consumption during the second trimester of pregnancy is associated with child energy intake and may influence anthropometry in early childhood, which is consistent with and suggestive of the presence of biological causal pathways alongside likely simultaneous contributions of social and environmental influences.

Association between Home Environment in Infancy and Child Movement Behaviors.

Introduction: An adequate balance of movement behaviors, including physical activity (PA), sleep, and screen time, is important for preventing excess weight gain in children. This study examined the relationship between the infant home environment and movement behaviors later in life. Methods: Pregnant women were recruited for a cohort study related to maternal and child development. The home environment was assessed for developmental stimulation, organization, and toys by the Pediatric Review of Children's Environmental Support and Stimulation (PROCESS) questionnaire when the child was 6 months of age. At 2 years of age, mother-reported child screen time, and child PA and sleep duration were estimated by accelerometry. Child behaviors were compared with the 24-hour Movement Guidelines (≥180 minutes/day of total PA, 11-14 hours/day of sleep, and ≤1 hour/day of screen time). Logistic regression was used to assess the relationship between the home environment and movement behaviors, adjusting for maternal and child covariates. Results: Mother/child dyads (n = 141) were mainly white (84.4%), and middle (32.8%) or low income (48.9%). All children (100%) met the PA guideline, some met the sleep guideline (71.6%), fewer met the screen-time guideline (44.7%), and only one-third (34.0%) met all three guidelines. Children who met the screen-time guideline lived in homes with more developmental stimulation and toys (p < 0.05). Children who met all 3 guidelines lived in homes with more organization and toys (p < 0.05). Conclusion: The infant home environment was associated with appropriate amounts of movement behaviors at 2 years. Promoting organization (i.e., routines) and toys in infancy may help facilitate nonscreen-based habits and healthy development. The clinical trial registration number is NCT01131117.

Patients with IVF complicated by moderate-to-critical OHSS experience increased thrombosis, GDM and neonatal NICU admission but slightly shorter gestation compared with matched IVF counterparts: A retrospective Chinese cohort study

BackgroundOvarian hyperstimulation syndrome (OHSS) is a common disease during controlled ovarian hyperstimulation treatment. However, the obstetric and neonatal outcomes of this group of patients are unknown. The aim of this study was to explore the effects of late moderate-to-critical OHSS on obstetric and neonatal outcomes.MethodsThis prospective observational study included 17,537 patients who underwent IVF/ICSI-fresh embryo transfer (ET) between June 2012 and July 2016 and met the inclusion criteria, including 7,064 eligible patients diagnosed with clinical pregnancy. Ultimately, 6,356 patients were allocated to the control group, and 385 patients who were hospitalized and treated at the center for late moderate-to-critical OHSS were allocated to the OHSS group. Then, propensity score matching analysis was performed, matching nine maternal baseline covariates and the number of multiple gestations; 385 patients with late moderate-to-critical OHSS were compared with a matched control group of 1,540 patients. The primary outcomes were the live birth rate, preterm delivery rate, miscarriage rate, gestational age at birth (weeks), obstetric complications and neonatal complications.ResultsThe duration of gestation in the matched control group was significantly higher than that in the OHSS group. The live birth delivery rate did not significantly differ between the OHSS and matched control groups. The incidence rates of the obstetric complications venous thrombosis (VT) and gestational diabetes mellitus (GDM), neonatal complications and the number of neonates admitted to the NICU were significantly higher in the OHSS group than in the matched control group.ConclusionsPregnant women undergoing IVF with fresh ET whose course is complicated by late moderate-to-critical OHSS appear to experience shortened gestation and increased obstetrical and neonatal complications compared with matched controls whose course is not complicated by OHSS. However, the live birth rate, average neonatal weight, and incidence rates of premature delivery, miscarriage, early abortion, hypertensive disorder of pregnancy (HDP), placenta previa (PP), intrahepatic cholestasis of pregnancy (ICP), and low neonatal birth weight (LBW) did not differ significantly between the two groups.

Maternal determinants of low birth weight among Indian children: Evidence from the National Family Health Survey-4, 2015-16.

ObjectiveLow birth weight (LBW) is a serious public health problem in low- and middle-income countries and a leading cause of death in the first month of life. In India, about 18% of children are born with LBW (<2500 grams) in 2015–16. In this study, we aim to examine the influence of maternal factors and socio-demographic covariates on LBW in Indian children.MethodsData were drawn from the fourth round of the National Family Health Survey (NFHS-4), conducted in 2015–16. A cross-sectional study was designed using a stratified two-stage sampling technique. Cross-tabulation, Pearson’s chi-squared test, and multivariate logistic regression analyses were employed to assess the impact of maternal factors and other covariates on children’s LBW.ResultsOf total participants (n = 147,762), 17.5% of children were found to be born with LBW. The study revealed that women who had prior experience of stillbirth (Adjusted odds ratio [AOR]: 1.20, 95% CI: 1.04–1.38) and any sign of pregnancy complications (AOR: 1.08, 95% CI: 1.05–1.11) were more likely to have LBW children, even after adjusting for a range of covariates. Maternal food diversity was found to a protective factor against children’s LBW. Women with underweight and anemic condition were associated with an increased likelihood of LBW children. Regarding maternity care, women who attended ≥4 ANC visits (AOR: 0.84, 95% CI: 0.80–0.88), took iron tablets/syrup during pregnancy (AOR: 0.94, 95% CI: 0.90–0.98), and delivered in a public health facility (AOR: 0.84, 95% CI: 0.79–0.88) were less likely to have LBW babies. Besides, various socio-demographic factors such as place of residence, caste, religion, education, wealth quintile, and geographical region were significantly associated with LBW of children.ConclusionInterventions are needed for adequate ANC utilization, improvement in public facility-based delivery, providing iron supplementation, and uptake of balanced energy-protein diet among pregnant mothers. Besides, special attention should be given to the socio-economically disadvantaged women to address adverse pregnancy and birth outcomes including LBW.

Nighttime sleep duration trajectories were associated with body mass index trajectories in early childhood.

The respective contribution of total, daytime and nighttime sleep duration in childhood obesity remains unclear. To assess the longitudinal association between developmental trajectories of sleep duration and BMI z-score in early childhood. Data were from the Melbourne INFANT program, a prospective cohort with 4-month-old infants being followed-up until age 60 months (n=528). Sleep duration (total, daytime, nighttime) and BMI z-score were measured using questionnaire at ages 4, 9, 18, 43 and 60 months. Group-based trajectory modelling was used to describe longitudinal trajectories from ages 4 to 60 months. Multivariable logistic regression was conducted to assess the association between sleep duration and BMI z-score trajectories. Three nighttime sleep duration trajectory groups were identified: "Long stable" (10.5 to 11.0hours, 61%), "catchup long" (8.0 to 11.5hours, 23%) and "short stable" (8.7 to 9.8hours, 16%) nighttime sleepers. BMI z-score trajectory groups were classified as "low-BMIz" (-1.5 to -0.5 unit, 21%), "mid-BMIz" (-0.5 to 0.5 unit, 58%) and "high-BMIz" (0.8 to 1.4 unit, 21%). With adjustment for child and maternal covariates, both "catchup long" (OR 3.69 95%CI 1.74, 7.92) and "long stable" nighttime sleepers (OR 4.27 95%CI 2.21, 8.25) revealed higher odds of being in the "mid-BMIz" than the "high-BMIz" group. By contrast, total or daytime sleep duration trajectories were not associated with BMI z-score trajectories. Longer nighttime, but not total or daytime, sleep duration was associated with lower BMI z-score trajectories in early childhood. Our findings reinforce the importance of nighttime sleep for healthy body-weight development in early childhood.

Associations of breastfeeding or formula feeding with infant anthropometry and body composition at 6 months.

The objective of this study was to investigate the associations of mode of feeding with infant anthropometric and body composition variables at 6 months of age. We studied 259 infants whose exclusive mode of feeding (breast or formula) to 1 month was confirmed. Standard anthropometric characteristics of the infants (weight, length and weight‐for‐length z scores) were obtained, and body composition (total fat mass, fat‐free mass, trunk fat mass and body fat percent) was measured using dual‐energy X‐ray absorptiometry (DXA) at 6 months (±12 days). General linear models were used to test the associations of mode of feeding with infant anthropometric and body composition variables at 6 months after adjustment for maternal and infant covariates. In this cohort of predominantly breastfed, White infants of highly educated mothers, fat‐free mass was lower (P = .002), and trunk fat mass (P = .032) and body fat percent (P < .001) were greater in breastfed infants than in formula‐fed infants at 6 months of age. After adjustment for covariates, total fat‐free mass was significantly lower (β = −372 g, [SE = 125, P = .003]), and body fat percent was significantly greater (β = 3.30, [SE = 0.91, P < .001]) in breastfed infants than in formula‐fed infants. No other significant associations were observed. These findings support those of previous studies reporting greater fat‐free mass in formula‐fed infants during the first 6 months of life. Additional research is warranted to explore whether differences in infant body composition by mode of feeding persist throughout the life course and to assess causality.

Placental cadmium, genetic variations, and birth size

Background: While maternal cadmium (Cd) burden has been associated with fetal growth markers (including birth weight and head circumference), associations of placental Cd with birth size is less clear. Further, the role of genetics in these associations has not been examined. We investigated associations of placental Cd with birth size and the role of placental genotypes in this relationship. Methods: Participants were 527 mother-child pairs from the OMEGA and Placental Microarray studies. Placental Cd was measured using Agilent 7500 ICP-MS. Placental single nucleotide polymorphisms (13 SNPs) related to metal transport, growth regulation, endocrine response, and cell signaling were genotyped. Multivariable linear regression models were used to examine associations of placental Cd (quartiles) with birth weight, ponderal index and head circumference, adjusted for maternal covariates. Potential effect modification by infant sex or placental SNPs were examined using interaction terms and stratified analyses. Results: The mean maternal age and pre-pregnancy BMI were 33.7 years (SD=4.4) and 23.9 (SD=0.04) respectively. The mean Cd level in placenta was 0.0039 ng/mg tissue (SD=0.0027 ng/mg tissue). Placental Cd was not associated with birth weight (ß=7.579, 95%CI: -38.597, 53.755), ponderal index (ß=-0.015, 95%CI: -2.385, 2.355) or head circumference (ß=-0.095, 95%CI: -0.503, 0.313). SNPs were also not associated with placental Cd and interaction terms with infant sex or SNPs were not significant.Conclusions: In the current study, placental Cd was not associated with birth size or placental genotypes.

Mothers’ Preventive Health Care Practices and Children’s Survival in Burkina Faso: Findings from Repeated Cross-sectional Household Surveys

The significant reduction in the level of child mortality in both developed and developing countries over recent decades has led to an improvement in children’s health. The implementation, monitoring, and evaluation of the health programs needed to reduce child mortality require determination and an understanding of the factors responsible for this reduction. This study investigated factors that have contributed to the recent improvement in the survival of children under five, focusing on the contribution of preventive health care in improving children’s survival rates in Burkina Faso.&#x0D; The data used come from baseline and end-line surveys designed to evaluate the impact of performance-based financing (PBF) on health programs in Burkina Faso. Using time-series for health districts and child-level logistic regression models, we estimated the effect of preventive health care, as summarized by the changes in the composite coverage index (CCI), on under-five child survival of temporal trends and covariates at the household, maternal, and child levels.&#x0D; At the health district level, a unit increase in standardized CCI was associated with an improvement in under-five child survival after adjustment for survey period effects. The linear regression analysis showed that a standardized unit increase in CCI was associated with an increase in the percentage of children under five who survive. At the child level, the logistic regression showed that a skilled attendant at birth (SBA), wealth index, and mother’s parity were associated with under-five children’s survival, after adjustment for the survey period effects and a set of household, maternal, and child-level covariates.&#x0D; Preventive health care is important in improving under-five children’s survival, whereas the effects of economic growth in Burkina Faso remain weak and inconsistent. Improved coverage of preventive health care interventions are likely to contribute to further reductions in under-five mortality in Burkina Faso.

Quantifying the Dynamics of HIV Decline in Perinatally Infected Neonates on Antiretroviral Therapy.

Mathematical modeling has provided important insights into HIV infection dynamics in adults undergoing antiretroviral treatment (ART). However, much less is known about the corresponding dynamics in perinatally infected neonates initiating early ART. From 2014 to 2017, HIV viral load (VL) was monitored in 122 perinatally infected infants identified at birth and initiating ART within a median of 2 days. Pretreatment infant and maternal covariates, including CD4 T cell counts and percentages, were also measured. From the initial cohort, 53 infants demonstrated consistent decline and suppressed VL below the detection threshold (20 copies mL) within 1 year. For 43 of these infants with sufficient VL data, we fit a mathematical model describing the loss of short-lived and long-lived infected cells during ART. We then estimated the lifespans of infected cells and the time to viral suppression, and tested for correlations with pretreatment covariates. Most parameters governing the kinetics of VL decline were consistent with those obtained previously from adults and other infants. However, our estimates of the lifespan of short-lived infected cells were longer than published values. This difference may reflect sparse sampling during the early stages of VL decline, when the loss of short-lived cells is most apparent. In addition, infants with higher pretreatment CD4 percentage or lower pretreatment VL trended toward more rapid viral suppression. HIV dynamics in perinatally infected neonates initiating early ART are broadly similar to those observed in other age groups. Accelerated viral suppression is also associated with higher CD4 percentage and lower VL.

Growth from Birth Through Six Months for Infants of Mothers in the “Women First” Preconception Maternal Nutrition Trial

To evaluate whether the fetal linear growth effects of maternal nutrition supplementation would be maintained through 6months postnatal age. The Women First trial was a multicountry, individually randomized clinical trial that compared the impact of maternal nutrition supplementation initiated preconception (Arm 1) vs at ∼11weeks of gestation (Arm 2), vs no supplement (Arm 3); the intervention was discontinued at delivery. Trial sites were in Democratic Republic of Congo, Guatemala, India, and Pakistan. Analysis includes 2421 infants born to 2408 randomized women. Primary outcome was the trajectory of length-for-age z scores (LAZ) by arm, based on assessments at birth and 1, 3, and 6months. We fitted longitudinal models on growth from birth to 6months using generalized estimating equations; maternal intervention effects were evaluated, adjusting for site and baseline maternal covariates. Linear growth for Arms 1 and 2 was statistically greater than for Arm 3 in 3 of the 4 countries, with average pairwise mean differences in LAZ of 0.25 (95% CI 0.15-0.35; P<.001) and 0.19 (95% CI 0.09-0.28; P<.001), respectively. Compared with Arm 3, average overall adjusted relative risks (95% CI) for stunting (LAZ <-2) were lower for Arms 1 and 2: 0.76 (0.66-0.87; P<.001) and 0.77 (0.67-0.88; P<.001), respectively. Improved linear growth in early infancy observed for the 2 intervention arms supports the critical importance of maternal nutrition before conception and in the early phase of gestation. ClinicalTrials.gov: NCT01883193.