RESUMO
CONTEXT: Breast milk composition is influenced by many factors, ranging from maternal nutritional status to infant sex. Previous studies have explored the relationship between maternal body mass index (BMI) and breast milk composition; however, the findings have been inconsistent and controversial. OBJECTIVE: To systematically review the evidence on the association of maternal weight and BMI with breast milk composition. DATA SOURCES: The PubMed and Scopus databases were searched up to May 3, 2023, using the following search strategy: ("maternal weight" OR "maternal BMI" OR "mother's weight" OR "mother's BMI") AND ("maternal milk" OR "human milk" OR "breast milk"). DATA EXTRACTION: A total of 83 publications, involving data from more than 11â310 lactating women, were identified. All extracted data were compiled, compared, and critically analyzed. DATA ANALYSIS: Overall, maternal BMI was associated with higher levels of leptin and insulin, and the ratio of omega-6 to omega-3 polyunsaturated fatty acids in breast milk. However, no conclusive associations were found between maternal BMI and the levels of energy, macronutrients, micronutrients, and other components of breast milk. CONCLUSIONS: This systematic review provides robust evidence supporting a positive correlation between maternal BMI and breast milk concentrations of leptin, insulin, and the omega-6 to omega-3 polyunsaturated fatty acid ratio. Nevertheless, disparities in findings are noticeable for other constituents of breast milk. To comprehensively grasp the influence of maternal weight and BMI on breast milk composition, further research endeavors are imperative. SYSTEMATIC REVIEW REGISTRATION: PROSPERO registration no. CRD42023458667.
RESUMO
OBJECTIVE: To investigate the impact of household food insecurity during the third trimester of pregnancy on the growth indicators of infants aged less than 6 months. DESIGN: Retrospective longitudinal study. SETTING: 137 healthcare centres (15 cities) in Khorasan Razavi province, Iran. Data were extracted from the Sina Electronic Health Record System (SinaEHR®). PARTICIPANTS: This study was conducted on 2481 mother and infant dyads during November 2016-March 2019. The Household Food Insecurity Access Scale (nine-item version) was used to measure food insecurity in the third trimester of pregnancy. Women who delivered singleton infants were included in the study, and anthropometric indices of infants were measured throughout the first 6 months of life. RESULTS: Approximately 67 % of the participants were food secure, while 33 % had varying degrees of food insecurity. The children born to the mothers in the food-insecure households were, respectively, 2·01, 3·03, and 3·83 times more likely to be stunted at birth (95 % CI 1·17, 3·46), 4 months (95 % CI 1·21, 7·61) and 6 months of age (95 % CI 1·37, 10·68) compared to their counterparts in the food-secure households. However, there were no significant differences in mean birth weight, birth height and head circumference at birth between the two groups. CONCLUSIONS: Household food insecurity during pregnancy is a risk factor for stunting in infants aged less than 6 months. Therefore, national nutrition programs could considerably support women in food-insecure households during and before pregnancy.
