Macronutrient Composition of Breast Milk in Tandem and Singular Breastfeeding: A Case–Control Study

Background: There is a significant lack of evidence and knowledge regarding tandem breastfeeding and breast milk composition. Purpose: This study aimed to compare the macronutrient content of colostrum and mature milk samples from mothers breastfeeding a single infant and those practicing tandem breastfeeding. Methods: This observational case – control study was conducted in western Turkey between May 2022 and June 2024. Milk samples from mothers practicing tandem breastfeeding (n = 10) were compared with those from mothers in the control group (n = 15). Breast milk samples were collected at 24-72 hours postpartum (colostrum) and again at 30 days postpartum (mature milk). The tandem breastfeeding group consisted of women who continued breastfeeding during pregnancy and fed both their newborns and older children after birth. The primary outcome was the comparison of energy and macronutrient values in breast milk. Breast milk analysis was conducted using the MIRIS Milk Analyzer. Results: There were no significant differences between the groups in breast milk macronutrient composition at either stage of lactation (colostrum and mature milk). However, maternal nutrient intake during the colostrum period showed statistically significant differences between the groups. Implications for Practice and Research: This study may assist nurses in providing better information to mothers who are tandem breastfeeding. Accurate and reassuring information about breastfeeding can be shared among mothers. Nurses can also create more effective care plans tailored to each mother’s specific needs by offering individualized guidance throughout the breastfeeding process. Furthermore, nurses may contribute to the development of breastfeeding support policies informed by such research.