Association between total fluid intake and breastfeeding practices and duration in postpartum women: a retrospective study

OBJECTIVE The study aimed to investigate the potential association between maternal total fluid intake at 3 months of infant age and breastfeeding practices and duration. DESIGN The study was embedded in the Tongji Maternal and Child Health Cohort. Information on total fluid intake for postpartum women was collected via telephone interviews at 3 months of infant age. Total fluid intake was categorized according to quartiles. SETTING Breastfeeding has beneficial health consequences for both mother and infant. The association between maternal total fluid intake and breastfeeding practices and duration remains unclear. POPULATION or SAMPLE 2,483 postpartum women-infants METHODS Logistic and multivariable linear regression models were used to investigate the association of total fluid intake with breastfeeding practices and duration. MAIN OUTCOME MEASURES Information on breastfeeding practices and duration were collected via telephone interviews at 3, 6, 12, and 24 months. Breastfeeding practice was estimated with full breastfeeding (defined as the practice of feeding an infant with exclusive breast milk, but water and water-based drinks without sugar are allowed) and any breastfeeding (defined as receiving any breast milk, including full breastfeeding, breastfeeding plus infant formula, other milk and/or complementary food). RESULTS Among 2,483 postpartum women-infants, 1350 (54.4%) and 966 (38.9%) received full breastfeeding at 3 and 6 months, respectively, and 2056 (82.8%), 1774 (71.4%), and 646 (36.8%) received any breastfeeding at 3, 6, and 12 months, respectively. The medium (interquartile range) of total fluid intake was 1600 ml (1250-2000 ml). 2,352 (94.7%) did not meet the recommended value (2600mL). Compared to mothers with the highest quartile of total fluid intake, those with the lowest quartile of total fluid intake were more likely to cease full breastfeeding at 3 months (adjusted odds ratio, 3.87; 95% confidence interval, 3.03–4.96) and at 6 months (adjusted odds ratio, 3.05; 95% CI = 2.38–3.92) of infant age, and to cease any breastfeeding at 12 months (adjusted odds ratio, 1.67; 95% confidence interval, 1.28–2.17). However, among mother-infants who received full breastfeeding at 3 months of age, fluid intake at 3 months of age was not significantly associated with breastfeeding practices at 6 and 12 months of age. Additionally, compared to the mothers with the highest quartile of total fluid intake, those with the lowest quartile of total fluid intake were more likely to cease breastfeeding early (adjusted β: -1.22; 95% confidence interval, -1.85–0.58). CONCLUSION The postpartum women with lower total fluid intake were more likely to cease breastfeeding. Short duration of breastfeeding was positively associated with limited total fluid intake in postpartum women. FUNDING This study is supported by the National Program on Basic Research Project of China (2019FY101003 and 2013FY114200). KEY WORDS postpartum, full breastfeeding, nutrients, nursing, fluid intake