Effect of a hospital policy of not accepting free infant formula on in-hospital formula supplementation rates and breast-feeding duration

Objective: To investigate the effect of public hospitals in Hong Kong not accepting free infant formula from manufacturers on in-hospital formula supplementation rates and breast-feeding duration. Design: Prospective cohort study. Setting: In-patient postnatal units of four public hospitals in Hong Kong. Subjects: Two cohorts of breast-feeding mother-infant pairs (n 2560). Cohort 1 (n 1320) was recruited before implementation of the policy to stop accepting free infant formula and cohort 2 (n 1240) was recruited after policy implementation. Participants were followed prospectively for 12 months or until they stopped breast-feeding. Results: The mean number of formula supplements given to infants in the first 24 h was 2.70 (SD 3.11) in cohort 1 and 1.17 (SD 1.94) in cohort 2 (P < 0.001). The proportion of infants who were exclusively breast-fed during the hospital stay increased from 17.7 % in cohort 1 to 41.3 % in cohort 2 (P < 0.001) and the risk of breast-feeding cessation was significantly lower in cohort 2 (hazard ratio = 0.81; 95 % CI 0.73, 0.90). Participants who non-exclusively breast-fed during the hospital stay had a significantly higher risk of stopping any or exclusive breast-feeding. Higher levels of formula supplementation also increased the risk of breast-feeding cessation in a dose-response pattern. Conclusions: After implementation of a hospital policy to pay market price for infant formula, rates of in-hospital formula supplementation were reduced and the rates of in-hospital exclusive breast-feeding and breast-feeding duration increased.