Longitudinal Infant Research Articles

A Novel Registration Framework for Aligning Longitudinal Infant Brain Tensor Images.

Registering longitudinal infant brain images is challenging, as the infant brain undergoes rapid changes in size, shape and tissue contrast in the first months and years of life. Diffusion tensor images (DTI) have relatively consistent tissue properties over the course of infancy compared to commonly used T1 or T2-weighted images, presenting great potential for infant brain registration. Moreover, groupwise registration has been widely used in infant neuroimaging studies to reduce bias introduced by predefined atlases that may not be well representative of samples under study. To date, however, no methods have been developed for groupwise registration of tensor-based images. Here, we propose a novel registration approach to groupwise align longitudinal infant DTI images to a sample-specific common space. Longitudinal infant DTI images are first clustered into more homogenous subgroups based on image similarity using Louvain clustering. DTI scans are then aligned within each subgroup using standard tensor-based registration. The resulting images from all subgroups are then further aligned onto a sample-specific common space. Results show that our approach significantly improved registration accuracy both globally and locally compared to standard tensor-based registration and standard fractional anisotropy-based registration. Additionally, clustering based on image similarity yielded significantly higher registration accuracy compared to no clustering, but comparable registration accuracy compared to clustering based on chronological age. By registering images groupwise to reduce registration bias and capitalizing on the consistency of features in tensor maps across early infancy, our groupwise registration framework facilitates more accurate alignment of longitudinal infant brain images.

Prenatal Maternal Psychological Distress During the COVID-19 Pandemic and Newborn Brain Development

Elevated maternal psychological distress during pregnancy is associated with altered fetal brain development. During the COVID-19 pandemic, prenatal maternal psychological distress more than doubled. To examine the association of the pandemic and rising maternal psychological distress with brain growth in newborns using quantitative 3-dimensional volumetric magnetic resonance imaging (MRI). This prospective cross-sectional study recruited mother-infant dyads at Children's National Hospital, Washington, DC, during the COVID-19 pandemic (June 1, 2020, to June 30, 2022) into a longitudinal infant brain development study and compared them with an existing normative healthy cohort (recruited March 1, 2014, to December 31, 2019). Exclusion criteria included multiple gestation pregnancy, known or suspected congenital infection, documented chromosomal abnormalities, or any maternal contraindication to MRI, as well as prenatal COVID-19 exposure. Infants with structural brain abnormalities or a postnatal confirmation of a genetic syndrome were excluded. Psychological distress during COVID-19 pandemic. Prenatal maternal mental health was evaluated using the Spielberger State-Trait Anxiety Inventory and the Perceived Stress Scale. Neonates underwent nonsedated brain MRI. An ordinary least squares linear regression model was used to measure the differences in regional brain volumes of neonates born before vs during the pandemic with and without exposure to elevated prenatal maternal psychological distress after adjustment for neonatal sex and gestational age at MRI and maternal age and educational level. A total of 159 mother-infant dyads were included in the analysis: 103 before and 56 during the pandemic (median gestational age of infants, 39.6 [IQR, 38.4-40.4] weeks; median maternal age, 34.5 [IQR, 31.0-37.0] years). Eighty-three infants (52.2%) were female. Among the mothers, 130 (81.8%) had a college degree and 87 (54.7%) had a graduate degree. Forty-four mothers (27.7%) identified as Asian, Hispanic, or multiracial; 27 (17.0%), as Black; and 88 (55.3%), as White. Scores on anxiety and stress measures were significantly increased in the pandemic cohort. Infants of mothers with elevated maternal distress showed median reductions in white matter (-0.36 [95% CI, -0.61 to -0.11] cm3; Q < .001), right hippocampal (-0.35 [95% CI, -0.65 to -0.06] cm3; Q = .04), and left amygdala (-0.49 [95% CI, -0.84 to -0.13] cm3; Q = .03) volumes compared with infants of mothers with low distress levels. After adjusting for the cohort effect of the pandemic, elevated trait anxiety remained significantly associated with decreased left amygdalar volumes (-0.71 [95% CI, -1.12 to -0.29]; Q < .001). In this cross-sectional study of maternal-infant dyads prior to and during the COVID-19 pandemic, regional neonatal brain volumes were associated with elevated maternal psychological distress.

7 Executive Function is Associated with the Development of Math Performance in Children Born Very Preterm

AbstractObjective:To examine associations between executive function (EF) domains (attentional control, information processing, cognitive flexibility, and goal setting) and math computation performance at 7 and 13 years in children born very preterm (VP; &lt;30 weeks' gestation), and secondly, to investigate the associations of 7-year EF with change in math performance from 7 to 13 years.Participants and Methods:In the prospective, longitudinal Victorian Infant Brain Studies (VIBeS) cohort of children born VP, assessment of EF and math performance was undertaken at 7 (n = 187) and 13 years (n = 174). Univariable and multivariable regression models (including all domains of EF) were used to examine associations between EF domains at both timepoints with math performance, as well as associations between EF at 7 years with change in math from 7 to 13 years.Results:At 7 and 13 years, all EF domains were positively associated with concurrent math performance, with multivariable models finding information processing, cognitive flexibility and goal setting independently contributed to math performance at both ages. All EF domains were positively associated with improvement in math performance from 7 to 13 years, with multivariable models finding that goal setting contributed unique variance to improvement in math over this period.Conclusions:This study provides evidence for a strong, consistent association between EF and math performance in children born VP and emphasizes the importance of goal setting capacity for later improvement in math performance.

Sources of gut microbiota variation in a large longitudinal Finnish infant cohort.

Although the infant gut microbiota has been extensively studied, comprehensive assessment on the microbiota determinants including technical variables has not been performed in large infant cohorts. We studied the effect of 109 variables on the 16S rRNA gene amplicon-based gut microbiota profiles of infants sampled longitudinally from three weeks to two years of life in the Finnish HELMi birth cohort. Spot faecal samples from both parents were included for intra-family analyses, totalling to 7657 samples from 985 families that were evaluated for beta-diversity patterns using permutational multivariate analysis on Bray-Curtis distances, and differential abundance testing and alpha-diversity for variables of interest. We also assessed the effect of different taxonomic levels and distance methods. In time point-specific models, the largest share of variation explained, up to 2-6%, were seen in decreasing order for the DNA extraction batch, delivery mode and related perinatal exposures, defecation frequency and parity/siblings. Variables describing the infant gastrointestinal function were continuously important during the first two years, reflecting changes in e.g., feeding habits. The effect of parity/siblings on infant microbiota was modified by birth mode and exposure to intrapartum antibiotics, exemplifying the tight interlinkage of perinatal factors relevant for infant microbiota research. In total, up to 19% of the biological microbiota variation in the infant gut could be explained. Our results highlight the need to interpret variance partitioning results in the context of each cohort's characteristics and microbiota processing. Our study provides a comprehensive report of key factors associated with infant gut microbiota composition across the two first years of life in a homogenous cohort. The study highlights possible important future research areas and confounding factors to be considered. This research was supported by Business Finland, Academy of Finland, Foundation for Nutrition Research and the Doctoral Program in Microbiology and Biotechnology, University of Helsinki, Finland.

Early introduction of complementaryfoods/drinks and milk feeding type in the Special Supplemental Nutrition Program for Women, Infantsand Children (WIC).

Infants younger than 4 months are not ready for complementary foods/drinks (any solid or liquid other than breast milk or infant formula). Almost half of USinfants participate in the Special Supplemental Nutrition Program for Women, Infantsand Children (WIC), which provides nutrition education and support to low-income families. We describe the prevalence of early introduction (<4 months) of complementary foods/drinks and examine the association of milk feeding type (fully breastfed, partially breastfedor fully formula fed) with early introduction of complementary foods/drinks. We used data from 3310 families in the longitudinal WIC Infant and Toddler Feeding Practices Study-2.We described the prevalence of early introduction of complementary foods/drinks and modeled the association of milk feeding type at Month 1 with early introduction of complementary foods/drinks using multi-variable logistic regression. Thirty-eight percent of infants were introduced early to complementary foods/drinks (<4 months). In adjusted models, infants who were fully formula fed or partially breastfed at Month 1 were 75% and 57%, respectively, more likely to be introduced early to complementary foods/drinks compared with fully breastfed infants. Almost twoin fiveinfants were given complementary foods/drinks early. Formula feeding at Month 1 was associated with higher odds of early introduction of complementary foods/drinks. There are opportunities to support families participating in WIC to prevent early introduction of complementary foods/drinks and promote child health.

Longitudinal prediction of postnatal brain magnetic resonance images via a metamorphic generative adversarial network

Missing scans are inevitable in longitudinal studies due to either subject dropouts or failed scans. In this paper, we propose a deep learning framework to predict missing scans from acquired scans, catering to longitudinal infant studies. Prediction of infant brain MRI is challenging owing to the rapid contrast and structural changes particularly during the first year of life. We introduce a trustworthy metamorphic generative adversarial network (MGAN) for translating infant brain MRI from one time point to another. MGAN has three key features: (i) Image translation leveraging spatial and frequency information for detail-preserving mapping; (ii) Quality-guided learning strategy that focuses attention on challenging regions. (iii) Multi-scale hybrid loss function that improves translation of image contents. Experimental results indicate that MGAN outperforms existing GANs by accurately predicting both tissue contrasts and anatomical details.

Implementation of a sample design for a survey of program participants using time-location sampling.

To assess the feeding practices and behaviors of women and young children participating in the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC), USDA currently funds the longitudinal WIC Infant and Toddler Feeding Practices Study-2 (WIC ITFPS-2). In 2013, the study used time-location sampling (TLS) to enroll a cohort of infants who participated in WIC around birth. The children are subsequently followed across their first six years of life, regardless of their participation in WIC, with an additional follow-up at age nine years. A woman may enroll her child in WIC either during pregnancy or postpartum. For this study, a representative sample of infants enrolled in WIC was desired. Because the associations between WIC prenatal support and education and feeding practices and behaviors are substantively important to this study, the sample needed to include both women enrolling their children prenatally and women enrolling their children postnatally. For prenatal WIC enrollees, we attempted to complete a prenatal interview with the mother prior to the child's birth. This paper describes the TLS approach used and the challenges addressed in implementation of the sample design and selection for the WIC ITFPS-2. Our approach generated a probability sample (subject to site geographic and size exclusions) using a stratified, multistage design, but there were challenges at each stage of selection. First, a WIC site was selected, and then newly enrolled WIC participants were sampled within selected sites during predetermined recruitment windows based on the site's average flow of new WIC enrollees. We discuss issues faced, including overcoming incomplete lists of individual WIC sites and discrepancies between projected new WIC enrollment counts and actual flow of new WIC enrollments during the recruitment period.

Association of Breastfeeding Practices During the First 3 Months with Infant Sleep Trajectories: A Prospective Cohort Study

BackgroundBreastfeeding has numerous effects on maternal and child health. The effect of breastfeeding on infant sleep remains inconclusive. ObjectivesWe aimed to examine whether full breastfeeding (FBF) during the first 3 mo is associated with longitudinal infant sleep trajectories in their first 2 y of life. MethodsThe study was embedded in the Tongji Maternal and Child Health Cohort study. Information on infant feeding practices was collected at 3 mo of age, and maternal/child pairs were assigned to the FBF or the non-FBF group (including partially breastfeeding and exclusive formula feeding) on the basis of feeding practices during the first 3 mo of life. Sleep data of infants were obtained at 3, 6, 12, and 24 mo. Total, night, and day sleep trajectories across 3 to 24 mo were estimated with group-based models. Each sleep trajectory was differentiated on the basis of sleep duration at 3 mo (long/moderate/short) and the interval from 6 to 24 mo (moderate/short). Multinomial logistic regression was used to investigate the association of breastfeeding practices with infant sleep trajectories. ResultsAmong the 4056 infants studied, 2558 (63.1%) received FBF for 3 mo. When compared with FBF infants, non-FBF infants had shorter sleep duration at 3, 6, and 12 mo (P < 0.01). Non-FBF infants were more likely to experience Moderate-Short (OR: 1.31; 95% CI: 1.06, 1.61) and Short-Short (OR: 1.56; 95% CI: 1.12, 2.16) total sleep trajectories and more likely to experience Moderate-Short (OR: 1.84; 95% CI: 1.22, 2.77), and Short-Moderate (OR: 1.40; 95% CI: 1.06, 1.85) night sleep trajectories than FBF infants. ConclusionsFull breastfeeding for ≥3 mo were positively associated with longer infant sleep duration. Infants fully breastfed were more likely to experience better sleep trajectories characterized by longer duration in their first 2 y of life. Full breastfeeding may benefit infants through healthy sleep.

Path Signature Neural Network of Cortical Features for Prediction of Infant Cognitive Scores.

Studies have shown that there is a tight connection between cognition skills and brain morphology during infancy. Nonetheless, it is still a great challenge to predict individual cognitive scores using their brain morphological features, considering issues like the excessive feature dimension, small sample size and missing data. Due to the limited data, a compact but expressive feature set is desirable as it can reduce the dimension and avoid the potential overfitting issue. Therefore, we pioneer the path signature method to further explore the essential hidden dynamic patterns of longitudinal cortical features. To form a hierarchical and more informative temporal representation, in this work, a novel cortical feature based path signature neural network (CF-PSNet) is proposed with stacked differentiable temporal path signature layers for prediction of individual cognitive scores. By introducing the existence embedding in path generation, we can improve the robustness against the missing data. Benefiting from the global temporal receptive field of CF-PSNet, characteristics consisted in the existing data can be fully leveraged. Further, as there is no need for the whole brain to work for a certain cognitive ability, a top K selection module is used to select the most influential brain regions, decreasing the model size and the risk of overfitting. Extensive experiments are conducted on an in-house longitudinal infant dataset within 9 time points. By comparing with several recent algorithms, we illustrate the state-of-the-art performance of our CF-PSNet (i.e., root mean square error of 0.027 with the time latency of 518 milliseconds for each sample).

Defective Monocyte Enzymatic Function and an Inhibitory Immune Phenotype in Human Immunodeficiency Virus-Exposed Uninfected African Infants in the Era of Antiretroviral Therapy.

BackgroundHuman immunodeficiency virus-exposed uninfected (HEU) infants are a rapidly expanding population in sub-Saharan Africa and are highly susceptible to encapsulated bacterial disease in the first year of life. The mechanism of this increased risk is still poorly understood. We investigated whether human immunodeficiency virus (HIV)-exposure dysregulates HEU immunity, vaccine-antibody production, and human herpes virus amplify this effect.MethodsThirty-four HIV-infected and 44 HIV-uninfected pregnant women were recruited into the birth cohort and observed up to 6 weeks of age; and then a subsequent 43 HIV-infected and 61 HIV-uninfected mother-infant pairs were recruited into a longitudinal infant cohort at either: 5–7 to 14–15; or 14–15 to 18–23 weeks of age. We compared monocyte function, innate and adaptive immune cell phenotype, and vaccine-induced antibody responses between HEU and HIV-unexposed uninfected (HU) infants.ResultsWe demonstrate (1) altered monocyte phagosomal function and B-cell subset homeostasis and (2) lower vaccine-induced anti-Haemophilus influenzae type b (Hib) and anti-tetanus toxoid immunoglobulin G titers in HEU compared with HU infants. Human herpes virus infection was similar between HEU and HU infants.ConclusionsIn the era of antiretroviral therapy-mediated viral suppression, HIV exposure may dysregulate monocyte and B-cell function, during the vulnerable period of immune maturation. This may contribute to the high rates of invasive bacterial disease and pneumonia in HEU infants.

Longitudinal Infant Functional Connectivity Prediction via Conditional Intensive Triplet Network.

Longitudinal infant brain functional connectivity (FC) constructed from resting-state functional MRI (rs-fMRI) has increasingly become a pivotal tool in studying the dynamics of early brain development. However, due to various reasons including high acquisition cost, strong motion artifact, and subject dropout, there has been an extreme shortage of usable longitudinal infant rs-fMRI scans to construct longitudinal FCs, which hinders comprehensive understanding and modeling of brain functional development at early ages. To address this issue, in this paper, we propose a novel conditional intensive triplet network (CITN) for longitudinal prediction of the dynamic development of infant FC, which can traverse FCs within a long duration and predict the target FC at any specific age during infancy. Targeting at accurately modeling of the progression pattern of FC, while maintaining the individual functional uniqueness, our model effectively disentangles the intrinsically mixed age-related and identity-related information from the source FC and predicts the target FC by fusing well-disentangled identity-related information with the specific age-related information. Specifically, we introduce an intensive triplet auto-encoder for effective disentanglement of age-related and identity-related information and an identity conditional module to mix identity-related information with designated age-related information. We train the proposed model in a self-supervised way and design downstream tasks to help robustly disentangle age-related and identity-related features. Experiments on 464 longitudinal infant fMRI scans show the superior performance of the proposed method in longitudinal FC prediction in comparison with state-of-the-art approaches.

Predicting Risk for Early Breastfeeding Cessation in Israel.

This study aimed to 1) Examine factors associated with cessation of exclusive breastfeeding in Israel and 2) Develop predictive models to identify women at risk for early exclusive breastfeeding cessation. The study used data from longitudinal national representative infant nutrition survey in Israel (n = 2119 participants). Logistic regression was used to identify risk factors and build predictive models. The rate of exclusive breastfeeding cessation increased from 45.4% at 2months to 85.7% at 6months. Five factors were significantly associated with higher odds of exclusive breastfeeding cessation at 2months: being a primapara, low educational level, lack of previous breastfeeding experience, negative attitude towards birth, and lack of intention to breastfeed. Six factors were significantly associated with higher odds of exclusive breastfeeding cessation at 6months: younger age, being in a relationship with a partner, lower religiosity level, cesarean delivery, not taking folic acid during pregnancy, and negative attitude towards birth. Both 2 and 6-months models had good predictive performance (C-statistic of .72 and .68, accordingly). This nationwide study successfully identified several predictors of exclusive breastfeeding cessation and created breastfeeding cessation prediction tools for two time periods (2 and 6months). The resulting tools can be applied to identify women at risk for stopping exclusive breastfeeding in hospitals or at community clinics. Further studies should examine practical aspects of applying these tools in practice and explore whether applying those tools can lead to higher exclusive breastfeeding rates.

The relationship between maternal prenatal and postnatal vegetable intake and repeated measures of infant vegetable intake frequency in a national U.S. sample

Experimental research suggests that passive flavor transfer from maternal diet to the infant via amniotic fluid and breastmilk may improve infant vegetable intake. This secondary analysis examined associations between maternal (prenatal and postnatal) and infant vegetable intake in 696 mothers with eligible dietary data from the U.S. longitudinal Infant Feeding Practices Study II. Adjusted mixed models examined associations between 4 levels of maternal vegetable intake (mean splits of high/low on prenatal and postnatal food frequency questionnaires) and repeated measures of infant vegetable intake frequency (times/day, from monthly surveys). Mothers were on average 29.5 years old, mostly non-Hispanic White (86.2%) and educated (84.0% ≥some college). In base models, mothers with consistently high vegetable intake (vs. consistently low) reported more frequent infant vegetable intake. In multivariable models, infant vegetable intake was significantly more frequent amongst mothers with consistently high prenatal/high postnatal intake (0.9 times/day) versus consistently low intake (0.8 times/day). In this sample, maternal vegetable consumption was associated with frequency of infant vegetable consumption; consistently high vegetable intake across prenatal and postnatal periods was most strongly associated with infant intake. While infant vegetable intake is multifactorial, maternal prenatal and postnatal vegetable intake appeared to have a small but significant influence.

Community-facility linkage models and maternal and infant health outcomes in Malawi's PMTCT/ART program: A cohort study.

BackgroundIn sub-Saharan Africa, 3 community-facility linkage (CFL) models—Expert Clients, Community Health Workers (CHWs), and Mentor Mothers—have been widely implemented to support pregnant and breastfeeding women (PBFW) living with HIV and their infants to access and sustain care for prevention of mother-to-child transmission of HIV (PMTCT), yet their comparative impact under real-world conditions is poorly understood.Methods and findingsWe sought to estimate the effects of CFL models on a primary outcome of maternal loss to follow-up (LTFU), and secondary outcomes of maternal longitudinal viral suppression and infant “poor outcome” (encompassing documented HIV-positive test result, LTFU, or death), in Malawi’s PMTCT/ART program. We sampled 30 of 42 high-volume health facilities (“sites”) in 5 Malawi districts for study inclusion. At each site, we reviewed medical records for all newly HIV-diagnosed PBFW entering the PMTCT program between July 1, 2016 and June 30, 2017, and, for pregnancies resulting in live births, their HIV-exposed infants, yielding 2,589 potentially eligible mother–infant pairs. Of these, 2,049 (79.1%) had an available HIV treatment record and formed the study cohort. A randomly selected subset of 817 (40.0%) cohort members underwent a field survey, consisting of a questionnaire and HIV biomarker assessment. Survey responses and biomarker results were used to impute CFL model exposure, maternal viral load, and early infant diagnosis (EID) outcomes for those missing these measures to enrich data in the larger cohort. We applied sampling weights in all statistical analyses to account for the differing proportions of facilities sampled by district. Of the 2,049 mother–infant pairs analyzed, 62.2% enrolled in PMTCT at a primary health center, at which time 43.7% of PBFW were ≤24 years old, and 778 (38.0%) received the Expert Client model, 640 (31.2%) the CHW model, 345 (16.8%) the Mentor Mother model, 192 (9.4%) ≥2 models, and 94 (4.6%) no model. Maternal LTFU varied by model, with LTFU being more likely among Mentor Mother model recipients (adjusted hazard ratio [aHR]: 1.45; 95% confidence interval [CI]: 1.14, 1.84; p = 0.003) than Expert Client recipients. Over 2 years from HIV diagnosis, PBFW supported by CHWs spent 14.3% (95% CI: 2.6%, 26.1%; p = 0.02) more days in an optimal state of antiretroviral therapy (ART) retention with viral suppression than women supported by Expert Clients. Infants receiving the Mentor Mother model (aHR: 1.24, 95% CI: 1.01, 1.52; p = 0.04) and ≥2 models (aHR: 1.44, 95% CI: 1.20, 1.74; p < 0.001) were more likely to undergo EID testing by age 6 months than infants supported by Expert Clients. Infants receiving the CHW and Mentor Mother models were 1.15 (95% CI: 0.80, 1.67; p = 0.44) and 0.84 (95% CI: 0.50, 1.42; p = 0.51) times as likely, respectively, to experience a poor outcome by 1 year than those supported by Expert Clients, but not significantly so. Study limitations include possible residual confounding, which may lead to inaccurate conclusions about the impacts of CFL models, uncertain generalizability of findings to other settings, and missing infant medical record data that limited the precision of infant outcome measurement.ConclusionsIn this descriptive study, we observed widespread reach of CFL models in Malawi, with favorable maternal outcomes in the CHW model and greater infant EID testing uptake in the Mentor Mother model. Our findings point to important differences in maternal and infant HIV outcomes by CFL model along the PMTCT continuum and suggest future opportunities to identify key features of CFL models driving these outcome differences.

The instability of functional connectomes across the first year of life

The uniqueness and stability of the adolescent and adult functional connectome has been demonstrated to be high (80–95 % identification) using connectome-based identification (ID) or “fingerprinting”. However, it is unclear to what extent individuals exhibit similar distinctiveness and stability in infancy, a developmental period of rapid and unparalleled brain development. In this study, we examined connectome-based ID rates within and across the first year of life using a longitudinal infant dataset at 1.5 month and 9 months of age. We also calculated the test–retest reliability of individual connections across the first year of life using the intraclass correlation coefficient (ICC). Overall, we found substantially lower infant ID rates than have been reported in adult and adolescent populations. Within-session ID rates were moderate and significant (ID = 48.94–70.83 %). Between-session ID rates were very low and not significant, with task-to-task connectomes resulting in the highest between-session ID rate (ID = 26.6 %). Similarly, average edge-level test-retest reliability was higher within-session than between-session (mean within-session ICC = 0.17, mean between-session ICC = 0.10). These findings suggest a lack of uniqueness and stability in functional connectomes across the first year of life consistent with the unparalleled changes in brain functional organization during this critical period.

Returning to Work and Breastfeeding Duration at 12 Months, WIC Infant and Toddler Feeding Practices Study-2.

Background: Returning to work can impact breastfeeding duration; limited data exist on how this may impact a lower income population. Methods: Data from U.S. Department of Agriculture's longitudinal study WIC Infant and Toddler Feeding Practices Study-2 were used to assess breastfeeding duration (<12 versus ≥12 months) by age of the baby when women first returned to work and work status (full time and part time). Multivariable logistic regression was used to determine the association of the timing of return to work, work status, and the combination (timing and work status) with breastfeeding duration. Results: Among women who had worked prenatally and initiated breastfeeding, 20.2% breastfed for ≥12 months. Compared to women who did not return to work, fewer women breastfed for ≥12 months if they returned full time or part time (34.1%, 12.0%, and 20.0%, respectively, p < 0.0001). Work status negatively impacted breastfeeding for ≥12 months (full-time adjusted odds ratio [aOR]: 0.24; 95% confidence interval [CI]: 0.13, 0.44 and part-time aOR: 0.51; 95% CI: 0.31, 0.83). Compared to women who did not return, those who returned full time within 3 months or returned part time >1 to 3 months after birth had lower odds of breastfeeding ≥12 months. Conclusions: Returning to work within 3 months after birth had a negative impact on breastfeeding for ≥12 months, particularly for those who returned full time. Efforts to support maternity leave and flexible work schedules could prolong breastfeeding durations among a low-income population. This study was a registered study at clinicaltrials.gov (NCT02031978).

Prenatal and Postnatal Experiences Predict Breastfeeding Patterns in the WIC Infant and Toddler Feeding Practices Study-2.

Objective: To examine pre- and postnatal experiential factors associated with desirable breastfeeding patterns in a nationally representative population of low-income women who prenatally enrolled in the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) and initiated breastfeeding. Materials and Methods: Using data from the longitudinal WIC Infant and Toddler Feeding Practices Study-2, multivariable, hierarchical logistic regression analyses identified prenatal and postnatal experiential factors associated with three breastfeeding patterns: (1) breastfeeding at 6 months, (2) breastfeeding at 1 year, and (3) breastfeeding at 1 year without introducing formula through age 6 months. Results: After controlling for covariates, one prenatal factor, breastfeeding intentions, and one postnatal factor, receipt of a doctor's recommendation to breastfeed, raised the odds of exhibiting the patterns analyzed. Another postnatal factor, returning to full-time employment before infant age 3 months, lowered the odds of exhibiting the patterns. Prior WIC participation significantly increased the odds of breastfeeding at 1 year, while postnatal employment before infant age 3 months significantly decreased the odds of exhibiting this pattern. Conclusions: Health care providers and those working in public health programs, including WIC, play an important role in helping low-income women mitigate shorter breastfeeding durations. Their efforts should continue focusing on bolstering women's prenatal breastfeeding intentions, reducing structural barriers to breastfeeding in the early postnatal period, particularly among those women returning to work, and connecting low-income families with WIC if they are not already enrolled in the program. This study is registered at clinicaltrials.gov as Feeding My Baby-A National WIC Study, NCT02031978.

Prevalence of thyroid dysfunction in postpartum women with suboptimal iodine and selenium and adequate iron status.

Postpartum women experience thyroid dysfunction at twice the prevalence of the general population. Adequate biosynthesis of thyroid hormones depends on three trace elements: iodine, selenium and iron. This study aimed to investigate thyroid dysfunction within a cohort of women at six months postpartum in relation to iodine, selenium and iron status. This cross-sectional study was part of an observational longitudinal cohort Mother and Infant Nutrition Investigation; data obtained at six months postpartum are reported. Mother-infant pairs (n=87) were recruited at three months postpartum and followed up at six months postpartum (n=78). Thyroid hormones (free triiodothyronine, free thyroxine, thyroid-stimulating hormone) and thyroid peroxidase antibodies were measured. Urinary iodine concentration, breast milk iodine concentration, serum thyroglobulin, plasma selenium, serum ferritin and serum soluble transferrin receptors were determined. Nonparametric data were expressed as median (25th, 75th percentile). Thyroid dysfunction was found in 18% of women, and 4% of women had iron deficiency. Median urinary iodine concentration was 85 (43, 134) µg/L, median breast milk iodine concentration was 59 (39, 109) µg/L, and median serum thyroglobulin at 11.4 (8.6, 18.6) µg/L, indicating iodine deficiency. Median plasma selenium concentration was 105.8 (95.6, 115.3) µg/L. Women with marginally lower plasma selenium concentration were 1.12% times more likely to have abnormal TSH concentrations (p=.001). There was a high prevalence of thyroid dysfunction. Plasma selenium concentration was the only significant predictor of the likelihood that women had thyroid dysfunction within this cohort, who were iodine deficient and mostly had adequate iron status. Strategies are required to improve both iodine and selenium status to better support maternal thyroid function.

Dietary Patterns and Growth From 12 to 24 Months of Age in African American Infants

Abstract Objectives To identify dietary patterns in 12-month-old African American infants and investigate their association with change in infant BMI z-score (BMIz) from 12 to 24 months. Methods The prospective longitudinal Infant Growth and Microbiome Study (IGram) enrolled African American women in their 3rd trimester of pregnancy who had a pre-pregnancy BMI &amp;gt;30 or &amp;lt;25 and followed them and their infants from birth to 24 months of age. At 12 months, mothers reported infant intake of 32 food items in the past 7 days using the CDC Infant Feeding Practices Study II questionnaire. With these data we employed principal component analysis to derive dietary patterns for infants aged 12 months. We used multiple regression to test associations of dietary pattern scores with change in infant BMIz between 12 and 24 months. Results IGram enrolled 368 infants at birth; 320 and 283 infants completed 12- and 24-month visits, respectively. The prevalence of BMIz &amp;gt; 2SD was 7.8% at 12 months and 6% at 24 months. We derived three dietary patterns which together explained 36% of the variation in the dataset. Based on the highest factor loadings for each pattern, they were named “Transitional/table food,” “Formula/baby cereal,” and “Fruit and vegetable/breast milk.” The former pattern included pancakes, pasta, rice, french fries, meat, eggs, and snack and sweet foods. Regression results suggested that, accounting for maternal pre-pregnancy obesity status, the “Fruit and vegetable/breast milk” pattern explained a small portion of the variance in BMIz increase from 12 to 24 months of age (β = 0.07, 95% CI = 0.01, 0.13, P = 0.03). Conclusions Preliminary findings of three distinct dietary patterns in African American infants at 12 months of age are an important first step in characterizing infant feeding patterns across the rich, longitudinal IGram dataset. A positive association of the “Fruit and vegetable/breast milk” pattern with change in infant BMIz from 12 to 24 months was unexpected and requires further investigation. Funding Sources An unrestricted donation from the American Beverage Foundation for a Healthy America to support the Children's Hospital of Philadelphia's Healthy Weight Program; the Research Institute of the Children's Hospital of Philadelphia; the National Center for Advancing Translational Sciences; the NIH NIDDK.

Longitudinal infant fNIRS channel-space analyses are robust to variability parameters at the group-level: An image reconstruction investigation

The first 1000 days from conception to two-years of age are a critical period in brain development, and there is an increasing drive for developing technologies to help advance our understanding of neurodevelopmental processes during this time. Functional near-infrared spectroscopy (fNIRS) has enabled longitudinal infant brain function to be studied in a multitude of settings. Conventional fNIRS analyses tend to occur in the channel-space, where data from equivalent channels across individuals are combined, which implicitly assumes that head size and source-detector positions (i.e. array position) on the scalp are constant across individuals. The validity of such assumptions in longitudinal infant fNIRS analyses, where head growth is most rapid, has not previously been investigated. We employed an image reconstruction approach to analyse fNIRS data collected from a longitudinal cohort of infants in The Gambia aged 5- to 12-months. This enabled us to investigate the effect of variability in both head size and array position on the anatomical and statistical inferences drawn from the data at both the group- and the individual-level. We also sought to investigate the impact of group size on inferences drawn from the data. We found that variability in array position was the driving factor between differing inferences drawn from the data at both the individual- and group-level, but its effect was weakened as group size increased towards the full cohort size (N = 53 at 5-months, N = 40 at 8-months and N = 45 at 12-months). We conclude that, at the group sizes in our dataset, group-level channel-space analysis of longitudinal infant fNIRS data is robust to assumptions about head size and array position given the variability in these parameters in our dataset. These findings support a more widespread use of image reconstruction techniques in longitudinal infant fNIRS studies.