Pregnancy weight gain in twin gestations and maternal and child health outcomes at 5 years.

OBJECTIVE: Current guidelines for maternal weight gain in twin pregnancy were established in the absence of evidence on its longer-term consequences for maternal and child health. We evaluated the association between weight gain in twin pregnancies and the risk of excess maternal postpartum weight increase, childhood obesity, and child cognitive ability. METHODS: We used 5-year follow-up data from 1000 twins born to 450 mothers in the Early Childhood Longitudinal Study-Birth Cohort, a nationally representative U.S. cohort of births in 2001. Pregnancy weight gain was standardized into gestational age- and prepregnancy body mass index (BMI)-specific z-scores. Excess postpartum weight increase was defined as ≥10 kg increase from prepregnancy weight. We defined child overweight/obesity as BMI ≥ 85th percentile, and low reading and math achievement as scores one standard deviation below the mean. We used survey-weighted multivariable modified Poisson models with a log link to relate gestational weight gain z-score with each outcome. RESULTS: Excess postpartum weight increase occurred in 40% of mothers. Approximately 28% of twins were affected by overweight/obesity, and 16 and 14% had low reading and low math scores. There was a positive linear relationship between pregnancy weight gain and both excess postpartum weight increase and childhood overweight/obesity. Compared with a gestational weight gain z-score 0 SD (equivalent to 20 kg at 37 weeks gestation), a weight gain z-score of +1 SD (27 kg) was associated with 6.3 (0.71, 12) cases of excess weight increase per 1000 women and 4.5 (0.81, 8.2) excess cases of child overweight/obesity per 100 twins. Gestational weight gain was not related to kindergarten academic readiness. CONCLUSIONS: The high prevalence of excess postpartum weight increase and childhood overweight/obesity within the recommended ranges of gestational weight gain for twin pregnancies suggests that these guidelines could be inadvertently contributing to longer-term maternal and child obesity.

Pregnancy Weight Gain by Gestational Age in Women with Uncomplicated Dichorionic Twin Pregnancies.

BACKGROUND: Twin pregnancies are at increased risk for adverse outcomes and are associated with greater gestational weight gain compared to singleton pregnancies. Studies that disentangle the relationship between gestational duration, weight gain and adverse outcomes are needed to inform weight gain guidelines. We created charts of the mean, standard deviation and select percentiles of maternal weight gain-for-gestational age in twin pregnancies and compared them to singleton curves. METHODS: We abstracted serial prenatal weight measurements of women delivering uncomplicated twin pregnancies at Magee-Womens Hospital (Pittsburgh, PA, 1998-2013) and merged them with the hospital's perinatal database. Hierarchical linear regression was used to express pregnancy weight gain as a smoothed function of gestational age according to pre-pregnancy BMI category. Charts of week- and day-specific values for the mean, standard deviation, and percentiles of maternal weight gain were created. RESULTS: Prenatal weight measurements (median: 11 [interquartile range: 9, 13] per woman) were available for 1109 women (573 normal weight, 287 overweight, and 249 obese). The slope of weight gain was most pronounced in normal weight women and flattened with increasing pre-pregnancy BMI (e.g. 50th percentiles of 6.8, 5.7, and 3.6 kg at 20 weeks and 19.8, 18.1, and 14.4 at 37 weeks in normal weight, overweight, and obese women, respectively). Weight gain patterns in twins diverged from singletons after 17-19 weeks. CONCLUSIONS: Our charts provide a tool for the classification of maternal weight gain in twin pregnancies. Future work is needed to identify the range of weight gain associated with optimal pregnancy health outcomes.

A Cooking Intervention to Increase Vegetable Consumption by Parents With Children Enrolled in an Early Head Start Home Visiting Program: A Pilot Study in Portland, Oregon, 2013-2014.

INTRODUCTION: Cooking interventions may improve diet quality. Most cooking interventions are delivered in group settings. Home visiting programs may be an appropriate mechanism for delivering such interventions to low-income families with young children. We conducted a pilot study to test the feasibility of using a cooking intervention delivered by home visitors to improve attitudes and behaviors related to vegetable consumption by low-income parents with children enrolled in a home visiting program. METHODS: We invited 121 parents with children enrolled in an Early Head Start Home Visiting program in Portland, Oregon, to participate. During 2013-2014, each month for 8 months, home visitors (n = 14) implemented 1 cooking activity plus 1 complementary activity focused on 12 vegetables. We collected pre- and post-intervention data on participants' cooking confidence and whether they tried and liked the selected vegetables. We also measured fidelity to protocol and home visitors' perception of intervention usability. RESULTS: Of 104 participants, 58 provided pre- and post-intervention data. We observed a significant increase in confidence in baking, roasting or grilling vegetables; cooking 6 of 10 vegetables; and trying 7 of 12 vegetables. Nearly all respondents participated in the monthly cooking activity (96%) and complementary activity (94%). Twelve of 14 home visitors reported that the intervention was acceptable, feasible, and easy to understand, and needed systems supports to implement. CONCLUSION: Cooking interventions may be a feasible approach to improving attitudes and behaviors related to vegetable consumption by low-income families with young children. Additional research is needed to assess the impact of such interventions on vegetable consumption.

The prevalence of rapid weight gain in infancy differs by the growth reference and age interval used for evaluation.

BACKGROUND: Infant rapid weight gain (RWG) may predict subsequent obesity, but there are inconsistencies in the growth references and age intervals used for assessment. METHODS: This study evaluated whether the prevalence of RWG (an increase of >0.67 in weight-for-age z-score) differed by growth reference (2006 WHO standards vs 2000 CDC references) and age interval of assessment (0-3, 0-6, 6-12 and 0-12 months). Pooled data from singleton term infants from two observational studies on maternal mood disorders during pregnancy were used (n = 161). Differences in RWG prevalence by growth reference and age interval were tested using Cochran's Q and McNemar's tests. RESULTS: The CDC reference produced a higher RWG prevalence (14% of infants additionally categorized as RWG, p < 0.0001) within the 0-3 month age interval compared to the WHO standards; this pattern was reversed for the 6-12 and 0-12 month intervals. RWG prevalence did not differ across age interval within the WHO standards, but did differ with the CDC references (range: 22% for 0-3 months to 4.2% for 6-12 months, p < 0.0001). CONCLUSIONS: Caution is advised when comparing studies with different criteria for RWG. Future studies should use the 2006 WHO standards and a consistent age interval of evaluation.

Gestational Weight Gain and Offspring Longitudinal Growth in Early Life.

BACKGROUND: Excessive gestational weight gain (GWG) increases the risk of childhood obesity, but little is known about its association with infant growth patterns. AIM: The aim of this study was to examine the association between GWG and infant growth patterns. METHODS: Pregnant women (n = 743) self-reported GWG at delivery, which we classified as inadequate, adequate or excessive based on the current guidelines. Offspring weight-for-age z-score (WAZ), length-for-age z-score (LAZ (with height-for-age (HAZ) in place of length at 36 months)) and body mass index z-score (BMIZ) were calculated at birth, 8, 18 and 36 months using the 2006 World Health Organization growth standards. Linear mixed models estimated the change in z-score from birth to 36 months by GWG. RESULTS: The mean (SD) WAZ was -0.22 (1.20) at birth. Overall, WAZ and BMIZ increased from birth to, approximately, 24 months and decreased from 24 to 36 months, while LAZ/HAZ decreased from birth through 36 months. Excessive GWG was associated with higher offspring WAZ and BMIZ at birth, 8 and 36 months, and higher HAZ at 36 months, compared with adequate GWG. Compared with the same referent, inadequate GWG was associated with smaller WAZ and BMIZ at birth and 8 months. CONCLUSION: Excessive GWG may predispose infants to obesogenic growth patterns, while inadequate GWG may not have a lasting impact on infant growth.

Maternal vitamin D status and infant anthropometry in a US multi-centre cohort study.

BACKGROUND: Maternal vitamin D status in pregnancy is linked to foetal growth and may impact infant growth. AIM: This study examined the association between maternal vitamin D status and infant anthropometry. SUBJECTS AND METHODS: Data came from n = 2473 mother-child pairs from the 12-site US Collaborative Perinatal Project (1959-1965). Maternal serum 25-hydroxyvitamin D (25(OH)D) was measured at ≤ 26 weeks gestation. Multivariate-adjusted linear mixed models were used to relate maternal vitamin D status to infant z-scores for length (LAZ), head circumference (HCZ), weight (WAZ) and BMI (BMIZ), measured at birth and 4, 8 and 12 months. RESULTS: Infants with maternal 25(OH)D ≥30 nmol/L vs <30 nmol/L had LAZ and HCZ measures 0.13 (95% CI = 0.03-0.23) and 0.20 (95% CI = 0.11-0.28) units higher, respectively, across the first year of life. Similar differences in WAZ and BMIZ at birth were resolved by 12 months of age due to interactions indicating steeper age slopes in infants with maternal 25(OH)D <30 nmol/L. CONCLUSION: Low maternal vitamin D status was associated with deficits at birth in infant weight and BMI that were recouped across the first year of life; associations with reduced measures of linear and skeletal growth were sustained from birth to 12 months.

Gestational Weight Gain and Adverse Birth Outcomes in Twin Pregnancies.

OBJECTIVE: To evaluate the association between gestational weight gain in twin pregnancies and small-for-gestational-age (SGA) and large-for-gestational-age (LGA) birth, preterm birth before 32 weeks of gestation, cesarean delivery, and infant death within each prepregnancy body mass index (BMI) category. METHODS: Data in this population-based study came from Pennsylvania-linked infant birth and death records (2003-2013). We studied 54,836 twins born alive before 39 weeks of gestation. Total pregnancy weight gain (kg) was converted to gestational age-standardized z scores. Multivariable modified Poisson regression models stratified by prepregnancy BMI were used to estimate associations between z scores and outcomes. A probabilistic bias analysis, informed by an internal validation study, evaluated the effect of BMI and weight gain misclassification. RESULTS: Gestational weight gain z score was negatively associated with SGA and positively associated with LGA and cesarean delivery in all BMI groups. The relation between weight gain and preterm birth was U-shaped in nonobese women. An increased risk of infant death was observed for very low weight gain among normal-weight women and for high weight gain among women without obesity. Most excess risks of these outcomes were observed at weight gains at 37 weeks of gestation that are equivalent to less than 14 kg or more than 27 kg in underweight or normal-weight women, less than 11 kg or more than 28 kg in overweight women, and less than 6.4 kg or more than 26 kg in women with obesity. The bias analysis supported the validity of the conventional analysis. CONCLUSION: Very low or very high weight gains were associated with the adverse outcomes we studied. If the associations we observed are even partially reflective of causality, targeted modification of pregnancy weight gain in women carrying twins might improve pregnancy outcomes.

One-year postpartum outcomes following a weight management intervention in pregnant women with obesity.

OBJECTIVE: This analysis was focused on 1-year maternal and infant follow-up of a randomized trial that tested a weight management intervention conducted during pregnancy. METHODS: One hundred fourteen women with obesity (mean BMI 36.7 kg/m(2) ) were randomly assigned at a mean of 15 weeks gestation to a weight management intervention or usual care control condition. The intervention ended at delivery and resulted in less gestational weight gain and a lower proportion of large-for-gestational-age newborns among intervention compared with control participants. The primary outcome at 12 months postpartum was maternal weight. Secondary outcomes included infant weight-for-age and weight-for-length z-scores. RESULTS: At 1 year, mothers in the intervention group weighed 96.3 ± 18.6 kg and those in the control group 99.7 ± 19.2 kg. There was no significant difference between groups in change in weight from randomization to 1 year postpartum (b = -0.47, 95% CI: -4.03 to 3.08). There was a significant main effect of group for infant weight-for-age z-scores (b = -0.40, 95% CI: -0.75 to -0.05) but not infant weight-for-length z-scores (b = -0.20, 95% CI: -0.59 to 0.20). CONCLUSIONS: A gestational weight management intervention did not influence maternal weight or infant weight-for-length at 1 year postpartum. Future studies may be warranted to determine whether extending prenatal interventions into the postpartum period would be beneficial for maternal and infant outcomes.

Harvest for Healthy Kids Pilot Study: Associations between Exposure to a Farm-to-Preschool Intervention and Willingness to Try and Liking of Target Fruits and Vegetables among Low-Income Children in Head Start.

BACKGROUND: Most US children do not meet recommendations for daily fruit and vegetable intake. OBJECTIVE: Our aim was to evaluate the hypothesis that at post-intervention, children exposed to the Harvest for Healthy Kids pilot study will have greater willingness to try and liking of target foods vs children in the comparison group, controlling for baseline differences. DESIGN: We conducted a quasi-experimental pilot study with comparison, low-intervention, and high-intervention groups. Pre- and post-intervention survey data were collected. PARTICIPANTS/SETTING: The intervention period was October 2012 to May 2013. The analysis sample was 226 children within the higher-level unit sample of five participating Head Start centers (Portland, OR); 231 children dropped out of or enrolled in Head Start mid-year, were absent during or refused to participate in the assessments, or were missing covariates. INTERVENTION: The comparison group received no intervention components; the low-intervention group received foodservice modifications; the high-intervention group received foodservice modifications and nutrition education. MAIN OUTCOME MEASURES: Willingness to try and liking of target foods were tested and analyzed as binary variables. STATISTICAL ANALYSES PERFORMED: McNemar's tests were used to assess differences between pre- and post-intervention scores by intervention group. Fixed slope, random intercept multilevel logistic models were used to assess associations between intervention group and post-intervention scores controlling for covariates, adjusting for baseline values, and accounting for center level clustering. RESULTS: The difference between pre- and post-intervention willingness to try and liking of target foods was statistically significant for a variety of foods; for example, 44.2% of children liked rutabaga pre-intervention compared with 78.1% post-intervention (P=0.004). Multilevel modeling indicated similar associations. CONCLUSIONS: The Harvest for Healthy Kids pilot study suggests a positive association between the intervention and willingness to try and liking for target foods among study participants. Additional research is needed to assess the impact of the program on fruit and vegetable intake.

Knowledge, attitudes, and beliefs that can influence infant feeding practices in American Indian mothers.

The promotion of healthy infant feeding is increasingly recognized as an important obesity-prevention strategy. This is relevant for American Indian populations that exhibit high levels of obesity and low compliance with infant feeding guidelines. The literature examining the knowledge, attitudes, and beliefs surrounding infant feeding within the American Indian population is sparse and focuses primarily on breastfeeding, with limited information on the introduction of solid foods and related practices that can be important in an obesity-prevention context. This research presents descriptive findings from a baseline knowledge, attitudes, and beliefs questionnaire on infant feeding and related behaviors administered to mothers (n=438) from five Northwest American Indian tribes that participated in the Prevention of Toddler Overweight and Teeth Health Study (PTOTS). Enrollment occurred during pregnancy or up to 6 months postpartum. The knowledge, attitudes, and beliefs questionnaire focused on themes of breastfeeding/formula feeding and introducing solid foods, with supplemental questions on physical activity. Knowledge questions were multiple choice or true/false. Attitudes and beliefs were assessed on Likert scales. Descriptive statistics included frequencies and percents and means and standard deviations. Most women knew basic breastfeeding recommendations and facts, but fewer recognized the broader health benefits of breastfeeding (eg, reducing diabetes risk) or knew when to introduce solid foods. Women believed breastfeeding to be healthy and perceived their social networks to agree. Attitudes and beliefs about formula feeding and social support were more ambivalent. This work suggests opportunities to increase the perceived value of breastfeeding to include broader health benefits, increase knowledge about solid foods, and strengthen social support.

Efficacy of a group-based dietary intervention for limiting gestational weight gain among obese women: a randomized trial.

OBJECTIVE: Observational studies suggest that minimal gestational weight gain (GWG) may optimize pregnancy outcomes for obese women. This trial tested the efficacy of a group-based weight management intervention for limiting GWG among obese women. METHODS: One hundred and fourteen obese women (BMI [mean ± SD] 36.7 ± 4.9 kg/m(2) ) were randomized between 7 and 21 weeks' (14.9 ± 2.6) gestation to intervention (n = 56) or usual care control conditions (n = 58). The intervention included individualized calorie goals, advice to maintain weight within 3% of randomization and follow the Dietary Approaches to Stop Hypertension dietary pattern without sodium restriction, and attendance at weekly group meetings until delivery. Control participants received one-time dietary advice. Our three main outcomes were maternal weight change from randomization to 2 weeks postpartum and from randomization to 34 weeks gestation, and newborn large-for-gestational age (birth weight >90th percentile, LGA). RESULTS: Intervention participants gained less weight from randomization to 34 weeks gestation (5.0 vs. 8.4 kg, mean difference = -3.4 kg, 95% CI [-5.1-1.8]), and from randomization to 2 weeks postpartum (-2.6 vs. +1.2 kg, mean difference = -3.8 kg, 95% CI [-5.9-1.7]). They also had a lower proportion of LGA babies (9 vs. 26%, odds ratio = 0.28, 95% CI [0.09-0.84]). CONCLUSIONS: The intervention resulted in lower GWG and lower prevalence of LGA newborns.

Growth patterns of Filipino children indicate potential compensatory growth.

BACKGROUND: The extent to which compensatory growth can occur after 2 years of age among children who were stunted in infancy has been questioned due, in part, to limitations in the data used to explore the issue. AIM: This study uses longitudinal data with multiple measurements over the entirety of the growth period to explore the potential for post-infancy compensatory growth in a developing country context. SUBJECTS AND METHODS: Data comes from >2000 Filipino youths from the Cebu Longitudinal Health and Nutrition Survey. Anthropometric data were collected bimonthly from 0 to 2 years, and at mean ages of 8, 11.5, 15.5 and 18.5 years. Growth indicators and influences on growth are compared among three groups: those that improved, tracked or worsened in change in height-for-age Z-score from 2 to 18.5 years of age. RESULTS: Those that improved in growth from 2 to 18.5 years grew slowest before 2 years of age, while the opposite was true among those that worsened. The reversal took place during the prepubescent growth spurt. Those that improved tended to have less educated but taller mothers. Regression to the mean and the potential for compensatory growth are discussed.

The association between diet and height in the postinfancy period changes with age and socioeconomic status in Filipino youths.

Whether the determinants of linear growth can have independent effects beyond the critical infancy period has been questioned. This research uses uniquely suited data from >2000 youths from the Cebu Longitudinal Health and Nutrition Study in the Philippines to examine the association between diet and height in the postinfancy period. Anthropometric, diet, and other data were collected bimonthly from 0 to 2 y, and at the mean ages of 8, 11.5, 15.5, and 18.5 y. Generalized Estimating Equations were used to quantify the mean effects of diet diversity and energy intake on height across increments demarcated by the postinfancy data (2-8.5, 8.5-11.5, 11.5-15.5, and 15.5-18.5 y). We examined whether the effects differed by socioeconomic status (SES) and age. Effects with P < 0.05 were considered significant. Each additional unit of diet variety (range 0-8 U) was associated with a significant 0.33-cm increase in height in boys. Each additional 100 kcal (4186 kJ) was associated with significant increases in height of 0.05 cm in boys, and 0.02 cm in girls. Significant interactions (P < 0.15) with SES showed that each 100 kcal increase in energy intake was associated with a 0.08-cm increase in height at low SES with no difference at high SES. In both boys and girls, the effects of energy intake decreased with age, as shown by a significant age interaction (P < 0.15). The methods used incorporate the longitudinal nature of the data to offer a unique examination of the association between diet and height in the postinfancy period.

Estimating body fat from anthropometry and isotopic dilution: a four-country comparison.

OBJECTIVE: The goal was to assess the ability of BMI to predict body fat (BF) among youths in four countries and identify the degree to which additional anthropometric measures improve this prediction. BMI is widely recommended as an indicator of overweight. However, whether BMI adequately estimates BF and has the same meaning in different ethnic groups and youths has been questioned. RESEARCH METHODS AND PROCEDURES: Data come from 456 Filipino, Chinese, Russian, and black South African youths, 6 to 16 years old. Percentage BF and fat mass index (FMI) were estimated by the deuterium dilution method. Skinfold thicknesses (triceps, subscapular, and suprailiac) and weight and height measures were collected. Percentage BF was regressed first on BMI and age and then with the addition of the skinfold measures. Linear models were run separately by country and sex. The models were repeated with FMI as the outcome. RESULTS: The R2 values from the percentage BF models ranged from 0.13 to 0.69 in the first models to 0.38 to 0.81 in the full models. The values were lowest among Russian males > or = 13 years and Russian females > or = 13 years of age in the reduced and full models, respectively, and were highest among Chinese females. Using FMI as the outcome did not meaningfully change the results. DISCUSSION: The ability of BMI to adequately predict BF and the additional predictivity of anthropometric measures varied widely across the samples, making its uniform use as a proxy for BF in youths from different countries questionable.