Body Composition Trajectories During the First 23 Months of Life Differ by HIV Exposure Among Infants in Western Kenya: A Prospective Study.

BACKGROUND: Infants who are HIV-exposed and uninfected have suboptimal growth patterns compared to those who are HIV-unexposed and uninfected. However, little is known about how these patterns persist beyond 1 year of life. OBJECTIVES: This study aimed to examine whether infant body composition and growth trajectories differed by HIV exposure during the first 2 years of life among Kenyan infants using advanced growth modeling. METHODS: Repeated infant body composition and growth measurements (mean: 6; range: 2-7) were obtained from 6 weeks to 23 months in the Pith Moromo cohort in Western Kenya (n = 295, 50% HIV-exposed and uninfected, 50% male). Body composition trajectory groups were fitted using latent class mixed modeling (LCMM) and associations between HIV exposure and growth trajectories were examined using logistic regression analysis. RESULTS: All infants exhibited poor growth. However, HIV-exposed infants generally grew suboptimally than unexposed infants. Across all body composition models except for the sum of skinfolds, HIV-exposed infants had a higher likelihood of belonging to the suboptimal growth groups identified by LCMM than the HIV-unexposed infants. Notably, HIV-exposed infants were 3.3 times more likely (95% CI: 1.5-7.4) to belong to the length-for-age z-score growth class that remained at a z-score of < -2, indicating stunted growth. HIV-exposed infants were also 2.6 times more likely (95% CI: 1.2-5.4) to belong to the weight-for-length-for-age z-score growth class that remained between 0 and -1, and were 4.2 times more likely (95% CI: 1.9-9.3) to belong to the weight-for-age z-score growth class that indicated poor weight gain besides stunted linear growth. CONCLUSIONS: In a cohort of Kenyan infants, HIV-exposed infants grew suboptimally compared to HIV-unexposed infants beyond 1 year of age. These growth patterns and longer-term effects should be further investigated to support the ongoing efforts to reduce early-life HIV exposure-related health disparities.

Neighbourhood walkability is associated with risk of gestational diabetes: A cross-sectional study in New York City.

BACKGROUND: Despite the links between neighbourhood walkability and physical activity, body size and risk of diabetes, there are few studies of neighbourhood walkability and risk of gestational diabetes (GD). OBJECTIVES: Assess whether higher neighbourhood walkability is associated with lower risk of GD in New York City (NYC). METHODS: Cross-sectional analyses of a neighbourhood walkability index (NWI) score and density of walkable destinations (DWD) and risk of GD in 109,863 births recorded in NYC in 2015. NWI and DWD were measured for the land area of 1 km radius circles around the geographic centroid of each Census block of residence. Mixed generalised linear models, with robust standard error estimation and random intercepts for NYC Community Districts, were used to estimate risk ratios for GD for increasing quartiles of each of the neighbourhood walkability measures after adjustment for the pregnant individual's age, race and ethnicity, parity, education, nativity, and marital status and the neighbourhood poverty rate. RESULTS: Overall, 7.5% of pregnant individuals experienced GD. Risk of GD decreased across increasing quartiles of NWI, with an adjusted risk ratio of 0.81 (95% Confidence Interval (CI) 0.75, 0.87) comparing those living in areas in the 4th quartile of NWI to those in the first quartile. Similarly, for comparisons of the 4th to 1st quartile of DWD, the adjusted risk ratio for GD was 0.77 (95% CI 0.71, 0.84). CONCLUSIONS: These analyses find support for the hypothesis that higher neighbourhood walkability is associated with a lower risk of GD. The analyses provide further health related support for urban design policies to increase walkability.

Weight Loss, Stability, and Low Weight Gain during Pregnancy among Individuals with Obesity: Associations with Adverse Perinatal Outcomes: An Observational Study.

OBJECTIVE: The safety of weight loss and low weight gain during pregnancy remains unclear. To determine how different patterns of gestational weight gain (GWG), including weight loss, stability, and low GWG relate to perinatal outcomes by prepregnancy obesity class. STUDY DESIGN: The study population included 29,408 singleton livebirths among pregnant people with obesity from Kaiser Permanente Northern California (2008-2013). Clinically measured GWG was grouped into meaningful categories (Adequate: reference, met 2009 National Academy of Medicine [NAM] Guidelines [5-9.1 kg], Excessive [>9.1 kg], Low [1-4.9 kg], Stable [±1 kg], Weight Loss [>1 kg]) or GWG Z-score quintiles. Modified Poisson regression was used to estimate risk of adverse outcomes, stratified by obesity class. Electronic health record data were used to define outcomes, including cesarean delivery, preterm birth, admission to the neonatal intensive care unit, small- and large-for-gestational age infants. RESULTS: Prevalence of weight stability and weight loss was 3.8 and 3.4%, respectively. Compared with those who gained within NAM, increased risk of small-for-gestational age was observed among those with weight loss among obesity class I (Risk Ratio (RR): 1.57, 95% confidence interval [CI]: 1.12, 2.19), obesity class II (RR: 2.18, 95% CI: 1.52, 3.13), and obesity class III (RR: 1.72, 95% CI: 1.21, 2.45). Weight loss was associated with a decreased risk of cesarean delivery among obesity class III, compared with NAM. CONCLUSION: Weight loss during pregnancy is associated with increased risk of small-for-gestational age among all obesity classes, but not other adverse perinatal outcomes and may reduce risk of cesarean delivery. Low weight gain and weight stability are not associated with risk of adverse outcomes among those with class III obesity. GWG guidelines may need to vary by obesity class. KEY POINTS: · Weight loss during pregnancy is associated with increased risk of small-for-gestational age among all obesity classes; but weight loss was not associated with other adverse perinatal outcomes.. · Among class III, low weight gain and weight stability are not associated with adverse perinatal outcomes.. · GWG guidelines may need to vary by obesity class..

Prenatal Weight Change Trajectories and Perinatal Outcomes among Twin Gestations.

OBJECTIVE: Despite an increase in twin pregnancies in recent decades, the Institute of Medicine twin weight gain recommendations remain provisional and provide no guidance for the pattern or timing of weight change. We sought to characterize gestational weight change trajectory patterns and examine associations with birth outcomes in a cohort of twin pregnancies. STUDY DESIGN: Prenatal and delivery records were examined for 320 twin pregnancies from a maternal-fetal medicine practice in Austin, TX 2011-2019. Prenatal weights for those with >1 measured weight in the first trimester and ≥3 prenatal weights were included in analyses. Trajectories were estimated to 32 weeks (mean delivery: 33.7 ± 3.3 weeks) using flexible latent class mixed models with low-rank thin-plate splines. Associations between trajectory classes and infant outcomes were analyzed using multivariable Poisson or linear regression. RESULTS: Weight change from prepregnancy to delivery was 15.4 ± 6.3 kg for people with an underweight body mass index, 15.4 ± 5.8 kg for healthy weight, 14.7 ± 6.9 kg for overweight, and 12.5 ± 6.4 kg for obesity. Three trajectory classes were identified: low (Class 1), moderate (Class 2), or high gain (Class 3). Class 1 (24.7%) maintained weight for 15 weeks and then gained an estimated 6.6 kg at 32 weeks. Class 2 (60.9%) exhibited steady gain with 13.5 kg predicted total gain, and Class 3 (14.4%) showed rapid gain across pregnancy with 21.3 kg predicted gain. Compared to Class 1, Class 3 was associated with higher birth weight z-score (ß = 0.63, 95% confidence interval [CI]: 0.31,0.96), increased risk for large for gestational age (IRR = 5.60, 95% CI: 1.59, 19.67), and birth <32 weeks (IRR = 2.44, 95%CI: 1.10, 5.4) that was attenuated in sensitivity analyses. Class 2 was associated with moderately elevated birth weight z-score (ß = 0.24, 95%CI: 0.00, 0.48, p = 0.050). CONCLUSION: Gestational weight change followed a low, moderate, or high trajectory; both moderate and high gain patterns were associated with increased infant size outcomes. Optimal patterns of weight change that balance risk during the prenatal, perinatal, and neonatal periods require further investigation, particularly in high-risk twin pregnancies. KEY POINTS: · A majority gained weight below IOM twin recommendations.. · Three patterns of GWC across pregnancy were identified.. · Moderate or high GWC was associated with infant size..

What stops us from eating: a qualitative investigation of dietary barriers during pregnancy in Punjab, Pakistan.

OBJECTIVE: Adequate dietary intake during pregnancy is vital for the health and nutritional status of both mother and fetus. The nutritional status of reproductive age women in Pakistan is poor, with 14 % being underweight (BMI < 18·5) and 42 % experiencing Fe deficiency anaemia. This may stem from beliefs, practices and other barriers influencing dietary intake. This qualitative study seeks to determine which factors impact dietary intake during pregnancy in rural Punjab. DESIGN: In-depth interviews and focus group discussions were conducted and then analysed using thematic analysis. SETTING: Three purposively selected rural districts (Sahiwal, Okara and Pakpatan) with the highest prevalence of maternal and child malnutrition in the province of Punjab, Pakistan. PARTICIPANTS: Mothers with children under age two (n 29) and healthcare providers with at least 5 years of experience working in the district (n 12). RESULTS: We identified a combination of physiological, socio-cultural and structural barriers that inhibited healthful dietary intake during pregnancy. The primary physiological barriers to optimal dietary intake and dietary practices included food aversions and food cravings. Food classification, fear of a difficult childbirth, fear of high blood pressure and household food politics were the principal socio-cultural barriers. Additionally, two structural barriers, inadequate antenatal counseling and a lack of affordable food options, were identified. CONCLUSIONS: Our study demonstrates that complex barriers prevent pregnant women in the Punjab area from consuming adequate dietary intake and that antenatal health education programmes and structural interventions are needed to support healthful dietary practices during this critical period.

The Relation of Birth Weight and Adiposity Across the Life Course to Semen Quality in Middle Age.

BACKGROUND: Studies of body mass index and semen quality have reported mixed results, but almost all were cross-sectional and many were conducted in selected populations. Longitudinal studies in population-based cohorts are necessary to identify how timing and duration of excess adiposity may affect semen quality. METHODS: In 193 members of the Child Health and Development Studies birth cohort, we examined associations of birth weight and adiposity at six time points spanning early childhood and adulthood with sperm concentration, motility, and morphology at mean age 44 years, as well as with corresponding 2010 World Health Organization (WHO) subfertility reference levels. RESULTS: Birth weight for gestational age percentile was positively associated with square-root sperm concentration (regression coefficient B [95% confidence interval] = 0.02 × 103 sperm/ml [0.004, 0.04]). Overweight/obesity in men's 20s was associated with lower percent progressive motility (B =-5.2 [-9.9, -0.63]), higher odds of low motility (odds ratio (OR) = 2.4 [1.3, 4.4]), and higher odds of poor morphology (OR = 1.9 [0.94, 3.8]). Those who were overweight/obese in their 20s were also more likely to meet two or three WHO subfertility criteria (OR = 3.9 [1.6, 9.4]) compared with normal-weight men. Each additional adult decade in which a participant was overweight/obese was associated with higher odds of low motility (OR = 1.3 [0.96, 1.6]) and higher odds of meeting two or three WHO subfertility criteria (OR = 1.5 [1.0, 2.2]). CONCLUSIONS: In our data, associations among adiposity and sperm concentration, motility, and morphology varied according to timing and duration of exposure, potentially reflecting different biological mechanisms that influence these semen parameters.

Prenatal exposure to airborne polycyclic aromatic hydrocarbons and childhood growth trajectories from age 5-14 years.

There is evidence that exposures to polycyclic aromatic hydrocarbons (PAH) and fine particles in air pollution are associated with higher childhood body mass index (BMI). Birth cohort analyses of prenatal exposures to PAH and child BMI Z-scores from age 5-14 years were conducted. African-American and Hispanic children born in the Bronx or Northern Manhattan, New York (1998-2006), whose mothers underwent personal air monitoring for airborne PAH exposure during pregnancy, were followed up with measurements of height and weight at approximate ages 5, 7, 9, 10, 11, 12.5 and 13.5 years. Multivariable generalized estimating equation analyses were used to relate prenatal airborne PAH exposures to child BMI Z-scores through time. The analyses adjusted for many known risk factors for childhood obesity and included interactions terms between age and exposure tertiles and age squared and exposure tertiles. In total, 535 children had at least one height and weight measure during follow-up. The prevalence of obesity was 20.6% at age 5 and increased across follow-ups until age 11 when it was 33.0%. At age 5, BMI Z-scores were significantly greater for children in the third tertile of exposure relative to the first tertile (0.35 Z-score units, 95% CI 0.09, 0.61, p = 0.007) and were non-significantly higher for the second tertile of exposure compared to the first tertile (0.25 Z-score units, 95% CI -0.02, 0.52, P = 0.075). The trajectories of BMI Z-scores by tertiles of exposure converged as the children aged, such that by age 11 years the estimated mean BMI Z-scores associated with each tertile of exposure were not different. Prenatal exposures to airborne PAH were associated with higher childhood BMI Z-scores at a young age, but growth trajectories converged by age 11 years. Accordingly, highly exposed children spend a greater proportion of their childhood with higher BMI Z-scores.

Prepregnancy obesity is associated with cognitive outcomes in boys in a low-income, multiethnic birth cohort.

BACKGROUND: Maternal obesity and high gestational weight gain (GWG) disproportionally affect low-income populations and may be associated with child neurodevelopment in a sex-specific manner. We examined sex-specific associations between prepregnancy BMI, GWG, and child neurodevelopment at age 7. METHODS: Data are from a prospective low-income cohort of African American and Dominican women (n = 368; 44.8% male offspring) enrolled during the second half of pregnancy from 1998 to 2006. Neurodevelopment was measured using the Wechsler Intelligence Scale for Children (WISC-IV) at approximately child age 7. Linear regression estimated associations between prepregnancy BMI, GWG, and child outcomes, adjusting for race/ethnicity, marital status, gestational age at delivery, maternal education, maternal IQ and child age. RESULTS: Overweight affected 23.9% of mothers and obesity affected 22.6%. At age 7, full-scale IQ was higher among girls (99.7 ± 11.6) compared to boys (96.9 ± 13.3). Among boys, but not girls, prepregnancy overweight and obesity were associated with lower full-scale IQ scores [overweight ß: - 7.1, 95% CI: (- 12.1, - 2.0); obesity ß: - 5.7, 95% CI: (- 10.7, - 0.7)]. GWG was not associated with full-scale IQ in either sex. CONCLUSIONS: Prepregnancy overweight and obesity were associated with lower IQ among boys, but not girls, at 7 years. These findings are important considering overweight and obesity prevalence and the long-term implications of early cognitive development.

Prepregnancy overweight and obesity are associated with impaired child neurodevelopment.

The authors examined the relationship of prepregnancy body mass index (BMI) and gestational weight gain (GWG) with child neurodevelopment. Mother-child dyads were a subgroup (n = 2,084) of the Child Health and Development Studies from the Oakland, California, area enrolled during pregnancy from 1959 to 1966 and followed at child age 9 years. Linear regression was used to examine associations between prepregnancy BMI, GWG, and standardized Peabody Picture Vocabulary Test and Raven Progressive Matrices scores and to evaluate effect modification of GWG by prepregnancy BMI. Before pregnancy, 77% of women were normal weight, 8% were underweight, 11% were overweight, and 3% were obese. Associations between GWG and child outcomes did not vary by prepregnancy BMI, suggesting no evidence for interaction. In multivariable models, compared to normal prepregnancy BMI, prepregnancy overweight and obesity were associated with lower Peabody scores (b: -1.29; 95% CI [-2.6, -0.04] and b: -2.7; 95% CI [-5.0, -0.32], respectively). GWG was not associated with child Peabody score [b: -0.03 (95% CI: -0.13, 0.07)]. Maternal BMI and GWG were not associated with child Raven score (all P >0.05). Maternal prepregnancy overweight and obesity were associated with lower scores for verbal recognition in mid-childhood. These results contribute to evidence linking maternal BMI with child neurodevelopment. Future research should examine the role of higher prepregnancy BMI values and the pattern of pregnancy weight gain in child cognitive outcomes.

Gestational weight gain and obesity, adiposity and body size in African-American and Dominican children in the Bronx and Northern Manhattan.

Gestational weight gain (GWG) is potentially modifiable and is associated with infant size and body composition; however, long-term effects on childhood obesity have not been reported among multi-ethnic urban populations. We examined the association between GWG and child anthropometric measures and body composition at 7 years [waist circumference (WC), body mass index z-score (BMIZ), obesity (BMIZ ≥95%ile) and bioelectrical impedance analysis estimates of percentage body fat (%fat)] in African-American and Dominican dyads (n = 323) in the Columbia Center for Children's Environmental Health prospective birth cohort study from 1998 to 2013. Linear and logistic regression evaluated associations between excessive GWG [>Institute of Medicine (IOM) 2009 guidelines] and outcomes, adjusting for pre-pregnancy BMI and covariates. Pre-pregnancy BMI (mean ± standard deviation, all such values) and total GWG were 25.8 ± 6.2 kg m(-2) (45% overweight/obese) and 16.4 ± 7.9 kg (64% > IOM guidelines), respectively. Excessive GWG was associated with higher BMIZ {0.44 [95% confidence interval (CI): 0.2, 0.7], P < 0.001}, WC [ß: 2.9 cm (95% CI: 1.1, 4.6), P = 0.002], %fat at 7 years [ß: 2.2% (95% CI: 1.0, 3.5), P = 0.001)] and obesity [odds ratio: 2.93 (95% CI: 1.5, 5.8), P = 0.002]. Pre-pregnancy BMI was positively associated with child size, adiposity and obesity (all P < 0.05). Excessive GWG was highly prevalent and was associated with child obesity, greater percentage body fat and abdominal adiposity. Strategies to support healthy GWG are warranted to promote healthy growth and prevent childhood obesity.

The Pattern of Gestational Weight Gain is Associated with Changes in Maternal Body Composition and Neonatal Size.

OBJECTIVES: The pattern of gestational weight gain (GWG) reflects general nutrient availability to support growing fetal and maternal compartments and may contribute to later health, but how it relates to changes in maternal body composition is unknown. We evaluated how the pattern of GWG related to changes in maternal body composition during pregnancy and infant size at birth. METHODS: A prospective, multi-ethnic cohort of 156 pregnant women and their infants was studied in New York City. Prenatal weights were used to estimate total and rate (kg/week) of GWG by trimester. Linear regression models evaluated the association between trimester-specific GWG group (low, medium, high GWG) [total (low ≤25, high ≥75 percentile) or rate (defined by tertiles)] and infant weight, length and maternal body composition changes from 14 to 37 weeks, adjusting for covariates. RESULTS: Compared to the low gain group, medium/high rate of GWG in the second trimester and high rate of GWG in the third trimester were associated with larger gains in maternal fat mass (ß range for fat Δ = 2.86-5.29 kg, all p < 0.01). For infant outcomes, high rate of GWG in the second trimester was associated with higher birth weight (ß = 356 g, p = 0.001) and length (ß = 0.85 cm, p = 0.002). First and third trimester GWG were not associated with neonatal size. CONCLUSIONS: The trimester specific pattern and rate of GWG reflect changes in maternal body fat and body water, and are associated with neonatal size, which supports the importance of monitoring trimester-specific GWG.

Changes in soluble transferrin receptor and hemoglobin concentrations in Malawian mothers are associated with those values in their exclusively breastfed, HIV-exposed infants.

Infant iron status at birth is influenced by maternal iron status during pregnancy; however, there are limited data on the extent to which maternal iron status is associated with infant iron status during exclusive breastfeeding. We evaluated how maternal and infant hemoglobin and iron status [soluble transferrin receptors (TfR) and ferritin] were related during exclusive breastfeeding in HIV-infected women and their infants. The Breastfeeding, Antiretrovirals, and Nutrition Study was a randomized controlled trial in Lilongwe, Malawi, in which HIV-infected women were assigned with a 2 × 3 factorial design to a lipid-based nutrient supplement (LNS), or no LNS, and maternal, infant, or no antiretroviral drug, and followed for 24 wk. Longitudinal models were used to relate postpartum maternal hemoglobin (n = 1926) to concurrently measured infant hemoglobin, adjusting for initial infant hemoglobin values. In a subsample, change in infant iron status (hemoglobin, log ferritin, log TfR) between 2 (n = 352) or 6 wk (n = 167) and 24 wk (n = 519) was regressed on corresponding change in the maternal indicator, adjusting for 2 or 6 wk values. A 1 g/L higher maternal hemoglobin at 12, 18, and 24 wk was associated with a 0.06 g/L (P = 0.01), 0.10 g/L (P < 0.001), and 0.06 g/L (P = 0.01), respectively, higher infant hemoglobin. In the subsample, a reduction in maternal log TfR and an increase in hemoglobin from initial measurement to 24 wk were associated with the same pattern in infant values (log TfR ß = -0.18 mg/L, P < 0.001; hemoglobin ß = 0.13 g/L, P = 0.01). Given the observed influence of maternal and initial infant values, optimizing maternal iron status in pregnancy and postpartum is important to protect infant iron status. This trial was registered at clinicaltrials.gov as NCT00164736.

Neighborhood Diversity Is Good for Your Health: An Example of Racial/Ethnic Integration and Preterm Birth in Texas.

Racial concentration of neighborhoods is often associated with the risk of preterm birth (PTB) for women. This study examined differences between racially diverse and racially concentrated neighborhoods when examining preterm birth. Individual-level data were obtained from Texas natality files for 2009-2011, and neighborhood-level (i.e., census tract) data were obtained from the decennial census in 2010 and the American Community Survey 2005-2009. We used multilevel modeling to assess the association between neighborhood racial diversity and odds of PTB, after controlling for individual characteristics, neighborhood poverty, and population density. We found that neighborhood racial diversity and concentration matter for PTB. Results suggest that systemic racism is still key to understanding PTB. Furthermore, findings support policies that prevent displacement from gentrification of diverse neighborhoods and promote equal access to health-related resources for women in predominantly Black, Hispanic, and/or immigrant neighborhoods.

Postpartum Obesity Is Associated With Increases in Child Adiposity in Midchildhood in a Cohort of Black and Dominican Youth.

Background: Obesity disproportionately affects marginalized and low-income populations. Birth parent obesity from the prenatal period and childhood has been associated with child obesity. It is unknown whether prenatal or postnatal birth parent obesity has differential effects on subsequent changes in adiposity and metabolic health in children. Objectives: We evaluated how birth parent obesity 7 y after delivery was associated with child body composition changes and cardiometabolic health in midchildhood and further assessed the influence of the perinatal and postpartum period on associations. Methods: Black and Dominican pregnant individuals were enrolled, and dyads (n = 319) were followed up at child age 7 and 9 y. Measures included, height, weight, waist circumference (WC), and percent body fat (BF%). Multiple linear regression was used to relate postpartum weight status with child outcomes accounting for attrition, and a series of secondary analyses were conducted with additional adjustment for perinatal weight status, gestational weight gain (GWG), and/or long-term weight retention to evaluate how these factors influenced associations. Results: Almost one-quarter (23%) of birth parents and 24.1% children were classified with obesity at child age 7 y, while at 9 y, 30% of children had obesity. Birth parent obesity at child age 7 y was associated with greater changes, from ages 7 to 9 y, in child BMI z-score (ß: 0.13; 95% CI: 0.02, 0.24) and BF% (ß: 1.15; 95% CI: 0.22, 2.09) but not obesity at age 9 y. All observed associations crossed the null after additional adjustment for prenatal factors. Conclusions: Birth parent obesity at 7-y postpartum is associated with greater gains in child BMI z-score and BF% in midchildhood. These associations diminish after accounting for prenatal size, suggesting a lasting impact of the perinatal environment and that interventions supporting families from the prenatal period through childhood are needed.

Maternal weight loss during exclusive breastfeeding is associated with reduced weight and length gain in daughters of HIV-infected Malawian women.

Maternal weight loss during exclusive breastfeeding may influence the growth of exclusively breast-fed infants through impaired quality or quantity of breast milk. This study evaluated how maternal weight loss from 2 to 24 wk postpartum was related to infant weight and length gain in 1309 lactating HIV-infected mothers and their exclusively breast-fed infants. Malawian mother-infant pairs in the Breastfeeding, Antiretrovirals, and Nutrition Study were randomized with a 2 × 3 factorial design to a 2-arm nutritional intervention with a lipid-based nutrient supplement (LNS), meeting nutritional needs of lactation, or no LNS and a 3-arm antiretroviral (ARV) intervention (maternal, infant, or no ARV regimen). Linear regression models were used to relate maternal weight loss (weight loss vs. no weight loss) to infant weight and length gain from birth to 24 mo, stratifying by gender and controlling for maternal BMI at 2 wk (mean ± SD: 23.2 ± 3.0 kg/m(2)) and interacting maternal BMI with weight loss. In adjusted models, compared with daughters of women who did not lose weight, length and weight gain were lower in daughters whose mothers had a lower BMI at 2 wk postpartum coupled with the weight loss. For example, among mothers with an initial BMI of 18 kg/m(2), daughters of those who lost weight gained less weight [ß = -0.29 kg (95% CI: -0.53, -0.06)] and length [ß = -0.88 cm (95% CI: -1.52, -0.23)] from birth to 24 wk than daughters of those who gained weight. Though effects were only observed in girls, suggesting possible gender differences in suckling and feeding behavior, these findings indicate that maternal weight loss with low energy reserves represents a risk factor for poor infant growth outcomes.

Breastfeeding, socioeconomic status, and long-term postpartum weight retention.

BACKGROUND: Almost half of all pregnant women in the United States gain weight above Institute of Medicine gestational weight gain guidelines. Breastfeeding has been shown to reduce weight retention in the first year postpartum; however, women with lower socioeconomic status (SES) tend to initiate breastfeeding less often than women with higher SES. We investigated associations between duration of breastfeeding with mother's long-term postpartum weight status at 4-10 years and evaluated whether the associations varied by SES. METHODS: Maternal and infant dyads (N = 2144 dyads) are from the Geographic Research on Wellbeing survey (GROW), 2012-2013, a long-term, cross-sectional follow-up of the Maternal and Infant Health Assessment (MIHA) based in California, USA. Pre-pregnancy body mass index (BMI) was obtained from self-report of height and weight during MIHA, while breastfeeding history and self-report of current body weight was collected at the 4-10 year GROW postpartum visit. SES score was derived from a composite score of percent federal poverty level and education and was dichotomized into High and Low SES groups at a score of three. Multivariable linear regression was used to examine association between breastfeeding and maternal weight status, and to examine for effect modification by SES. RESULTS: Average long-term weight retention 4-10 years postpartum was 4.0 kg. Fewer lower SES vs. higher SES women breast fed at least six months (51% versus 70%, p < .001) or ever breastfed (74% versus 89%, P < .001). Women who breastfed at least six months had lower long-term postpartum weight retention compared to those who did not (b = -1.06 kg, (-1.93, 0.25); p = 0.01); however, these association did not vary by SES. CONCLUSION: Six months of breastfeeding is associated with lower BMI at 4-10 years and lower body weight, and effects do not vary by SES. Future policies and guidelines should consider building an infrastructure that is supportive of longer breastfeeding duration. Moreover, further research is needed to identify the impact of additional behavioral and environmental factors on long-term maternal weight status. Understanding the drivers of excessive weight retention pospartum can help us not only improve the pregnant person's health but the health of their children.

Novel approaches to examining weight changes in pregnancies affected by obesity.

BACKGROUND: Current gestational weight change (GWC) recommendations for obese individuals were established with limited evidence of the pattern and timing of weight change across pregnancy. Similarly, the recommendation of 5-9 kg does not differentiate by the severity of obesity. OBJECTIVES: We sought to describe GWC trajectory classes by obesity grade and associated infant outcomes among a large, diverse cohort. METHODS: The study population included 22,355 individuals with singleton pregnancies, obesity (BMI ≥30.0 kg/m2), and normal glucose tolerance who delivered at Kaiser Permanente Northern California between 2008 and 2013. Obesity grade-specific GWC trajectories were modeled at 38 wk using flexible latent class mixed modeling (package lcmm) in R. Multivariable Poisson or linear regression models estimated the associations between the GWC trajectory class and infant outcomes (size-for-gestational age and preterm birth) by obesity grade. RESULTS: Five GWC trajectory classes were identified for each obesity grade, each with a distinct pattern of weight change before 15 wk (including loss, stability, and gain) followed by weight gain thereafter (low, moderate, and high). Two classes with high overall gain were associated with an increased risk for large for gestational age (LGA) in obesity grade 1 (IRR = 1.27; 95% CI: 1.10, 1.46; IRR = 1.47; 95% CI: 1.24, 1.74). Both high (IRR = 2.02; 95% CI: 1.61, 2.52; IRR = 1.98; 95% CI: 1.52, 2.58) and 2 moderate-gain classes (IRR = 1.40; 95% CI 1.14, 1.71; IRR = 1.51; 95% CI: 1.20, 1.90) were associated with LGA in grade 2, and only early loss/late moderate-gain class 3 (IRR = 1.30; 95% CI: 1.04, 1.62) was associated in grade 3. This class was also associated with preterm birth in grade 2. No associations were detected between GWC and small for gestational age (SGA). CONCLUSIONS: Among the pregnancies affected by obesity, GWC was not linear or uniform. Different patterns of high gain were associated with an increased risk for LGA with the greatest magnitude in obesity grade 2, whereas GWC patterns were not associated with SGA.

Neighborhood Food Environment and Birth Weight Outcomes in New York City.

Importance: Infants born with unhealthy birth weight are at greater risk for long-term health complications, but little is known about how neighborhood characteristics (eg, walkability, food environment) may affect birth weight outcomes. Objective: To assess whether neighborhood-level characteristics (poverty rate, food environment, and walkability) are associated with risk of unhealthy birth weight outcomes and to evaluate whether gestational weight gain mediated these associations. Design, Setting, and Participants: The population-based cross-sectional study included births in the 2015 vital statistics records from the New York City Department of Health and Mental Hygiene. Only singleton births and observations with complete birth weight and covariate data were included. Analyses were performed from November 2021 to March 2022. Exposures: Residential neighborhood-level characteristics, including poverty, food environment (healthy and unhealthy food retail establishments), and walkability (measured by both walkable destinations and a neighborhood walkability index combining walkability measures like street intersection and transit stop density). Neighborhood-level variables categorized into quartiles. Main Outcomes and Measures: The main outcomes were birth certificate birth weight measures including small for gestational age (SGA), large for gestational age (LGA), and sex-specific birth weight for gestational age z-score. Generalized linear mixed-effects models and hierarchical linear models estimated risk ratios for associations between density of neighborhood-level characteristics within a 1-km buffer of residential census block centroid and birth weight outcomes. Results: The study included 106 194 births in New York City. The mean (SD) age of pregnant individuals in the sample was 29.9 (6.1) years. Prevalence of SGA and LGA were 12.9% and 8.4%, respectively. Residence in the highest density quartile of healthy food retail establishments compared with the lowest quartile was associated with lower adjusted risk of SGA (with adjustment for individual covariates including gestational weight gain z-score: risk ratio [RR], 0.89; 95% CI 0.83-0.97). Higher neighborhood density of unhealthy food retail establishments was associated with higher adjusted risk of delivering an infant classified as SGA (fourth vs first quartile: RR, 1.12; 95% CI, 1.01-1.24). The RR for the association between density of unhealthy food retail establishments and risk of LGA was higher after adjustment for all covariates in each quartile compared with quartile 1 (second: RR, 1.12 [95% CI, 1.04-1.20]; third: RR, 1.18 [95% CI, 1.08-1.29]; fourth: RR, 1.16; [95% CI, 1.04-1.29]). There were no associations between neighborhood walkability and birth weight outcomes (SGA for fourth vs first quartile: RR, 1.01 [95% CI, 0.94-1.08]; LGA for fourth vs first quartile: RR, 1.06 [95% CI, 0.98-1.14]). Conclusions and Relevance: In this population-based cross-sectional study, healthfulness of neighborhood food environments was associated with risk of SGA and LGA. The findings support use of urban design and planning guidelines to improve food environments to support healthy pregnancies and birth weight.