Practices, predictors and consequences of expressed breast-milk feeding in healthy full-term infants.

Objective: To investigate the prevalence and predictors of expressed breast-milk feeding in healthy full-term infants and its association with total duration of breast-milk feeding.

Design: Prospective cohort study.

Setting: In-patient postnatal units of four public hospitals in Hong Kong.

Subjects: A total of 2450 mother-infant pairs were recruited in 2006-2007 and 2011-2012 and followed up prospectively for 12 months or until breast-milk feeding had stopped.

Results: Across the first 6 months postpartum, the rate of exclusive expressed breast-milk feeding ranged from 5·1 to 8·0 % in 2006-2007 and from 18·0 to 19·8 % in 2011-2012. Factors associated with higher rate of exclusive expressed breast-milk feeding included supplementation with infant formula, lack of previous breast-milk feeding experience, having a planned caesarean section delivery and returning to work postpartum. Exclusive expressed breast-milk feeding was associated with an increased risk of early breast-milk feeding cessation when compared with direct feeding at the breast. The hazard ratio (95 % CI) ranged from 1·25 (1·04, 1·51) to 1·91 (1·34, 2·73) across the first 6 months.

Conclusions: Mothers of healthy term infants should be encouraged and supported to feed directly at the breast. Exclusive expressed breast-milk feeding should be recommended only when medically necessary and not as a substitute for feeding directly at the breast. Further research is required to explore mothers' reasons for exclusive expressed breast-milk feeding and to identify the health outcomes associated with this practice.