Human Milk Glucose, Leptin, and Insulin Predict Cessation of Full Breastfeeding and Initiation of Formula Use.

Objective: We aimed to investigate prospective associations between milk bioactives related to metabolic health (glucose, insulin, leptin, C reactive protein [CRP], and interleukin 6 [IL-6]) and incident formula initiation at 3 and 6 months postpartum. Design: This study included 363 mother-infant dyads who were fully breastfed at 1 month and participated in the prospective Mothers and Infants Linked for Healthy Growth study from pregnancy to 6 months postpartum. Associations between milk glucose, leptin, insulin, CRP, and IL-6 at 1 and 3 months and incident formula feeding (FF) at 3 and 6 months, respectively, were tested using multiple logistic regression, adjusting for numerous potential confounders such as maternal age and prepregnancy body mass index. Results: At 3 months postpartum, 1-month glucose (odds ratio [OR] 0.45 [95% confidence interval (CI): 0.27-0.75], p ≤ 0.01) and smaller decreases in glucose from 1 to 3 months (OR 0.51 [95% CI: 0.28-0.92], p = 0.03) were associated with lower odds of FF, whereas 1-month leptin (OR 2.30 [95% CI: 1.30-4.07], p < 0.01) and larger increase in insulin (OR 1.86 [95% CI: 1.23-2.81], p < 0.01) and leptin (OR 2.17 [95% CI: 1.29-3.68], p < 0.01) from 1 to 3 months were associated with increased odds of FF. At 6 months, insulin increases (OR 2.08 [95% CI: 1.03-4.17], p = 0.04) were associated with higher odds of FF. Conclusions: In a cohort of women with established lactation, 1-month milk glucose, insulin, and leptin predicted initiation of FF at 3 months. Early milk composition may provide a window into mammary gland function, allowing identification of women at risk of not meeting their breastfeeding goals.

Association of Social and Community Factors with U.S. Breastfeeding Outcomes.

Objective: To explore, in a large, nationally representative U.S. sample of children, potential independent associations between social and community factors and breastfeeding outcomes, using the Social Ecological Model as a theoretical framework. Materials and Methods: A secondary data analysis of the 2011-2012 National Survey of Children's Health was conducted (N = 29,829). Multivariate logistic regression was performed to estimate associations between predictor variables (parental emotional support, neighborhood social support, neighborhood safety, neighborhood amenities, and medical home) and breastfeeding outcomes (breastfeeding initiation [BFI] and exclusive breastfeeding for 6 months [EBF6m]). For predictor variables reaching statistical significance in the adjusted models, we performed subgroup analyses by race-ethnicity. Results: After adjusting for individual- and family-level sociodemographic and maternal-child health factors, living in a neighborhood with 4 amenities was associated with 1.54 (95% confidence interval [CI] 1.06-2.23) times the odds of BFI, compared to children living in neighborhoods with no amenities. There was a negative association (adjusted odds ratio [aOR] 0.83; 95% CI 0.70-0.99) between neighborhood social support and BFI, although living in a supportive neighborhood was associated with 1.37 (95% CI 1.11-1.69) times the odds of EBF6m. There was a negative association (aOR 0.71; 95% CI 0.54-0.93) between perceived neighborhood safety and EBF6m. The observed associations differed by race-ethnicity. Conclusion: Community-level structural and social support factors influence breastfeeding outcomes, independent of previously described individual level sociodemographic factors, and the observed associations differ by race-ethnicity. These findings have implications for the development of "breastfeeding-friendly" communities and public policies.

Protocol for establishing an infant feeding database linkable with population-based administrative data: a prospective cohort study in Manitoba, Canada.

INTRODUCTION: Breast feeding is associated with many health benefits for mothers and infants. But despite extensive public health efforts to promote breast feeding, many mothers do not achieve their own breastfeeding goals; and, inequities in breastfeeding rates persist between high and low-income mother-infant dyads. Developing targeted programme to support breastfeeding dyads and reduce inequities between mothers of different socioeconomic status are a priority for public health practitioners and health policy decision-makers; however, many jurisdictions lack the timely and comprehensive population-level data on infant-feeding practices required to monitor trends in breastfeeding initiation and duration. This protocol describes the establishment of a population-based infant-feeding database in the Canadian province of Manitoba, providing opportunities to develop and evaluate breastfeeding support programme. METHODS AND ANALYSIS: Routinely collected administrative health data on mothers' infant-feeding practices will be captured during regular vaccination visits using the Teleform fax tool, which converts handwritten information to an electronic format. The infant-feeding data will be linked to the Manitoba Population Research Data Repository, a comprehensive collection of population-based information spanning health, education and social services domains. The linkage will allow us to answer research questions about infant-feeding practices and to evaluate how effective current initiatives promoting breast feeding are. ETHICS AND DISSEMINATION: Approvals have been granted by the Health Research Ethics Board at the University of Manitoba. Our integrative knowledge translation approach will involve disseminating findings through government and community briefings, presenting at academic conferences and publishing in scientific journals.