AbstractsBiology & Animal Science

Most U.S. mothers who feed their human milk (HM) to their infants now use pumps and bottles or cups to replace some or all feeding at the breast (FAB). Little is known about how mothers perceive or feel about these practices or how human milk expression (HME) may relate to longterm practices for feeding HM from breasts or bottles. Longitudinal qualitative data came from 20 mothers in upstate New York who pumped HM and whose infants were fed pumped HM. We interviewed women from pregnancy up to 1 year postpartum, and identified themes with content analysis of transcripts. Longitudinal quantitative data came from the 1,044 mothers in the Infant Feeding Practices Study II who fed and pumped HM 1.5-4.5 months postpartum. We used survival analyses to examine associations between mothers' HME frequency 1.5-4.5 months and the duration of any or exclusive HM and of FAB. In our qualitative sample, mothers appreciated that pumps and bottles let them share the bonding and burden of feeding infants. However, they found that HME and related tasks were unpleasant or time-consuming and that considerations for HME and bottle-feeding were reduced or absent while FAB. Mothers used data from HME and bottle-feeding sessions to understand their ability to meet their infants' needs. In our quantitative sample, mothers who pumped more often than the median had a significantly higher average hazard for stopping feeding any HM and for feeding HM exclusively, by 40% and 28% respectively, than those who pumped least often. Their hazard of stopping FAB changed over time, but remained significant until 6 months, when hazards were 6.4 times higher. For health professionals, these findings provide important insights into mothers' experiences pumping HM and having other caregivers feed it to their infants. Our data also suggest that highfrequency pumping may adversely affect the duration of HM feeding. These findings signal to policymakers that efforts to meet national goals for HM-feeding should include support for FAB and for HME at work. Finally, these findings are a call for researchers to investigate links between pumping and bottle-feeding HM and outcomes for infants and mothers.