Evaluating milk flow patterns using the high flow rate period during breast pumping

Breast pumping practices have scope for improvement. Breast milk weight measurement can be used to evaluate milk flow pattern dynamics during breast pumping. To determine inter-individual differences in milk flow patterns and their practical implications based on high milk flow rate period (HFP) data among Japanese women expressing breast milk using an electric pump. This cross-sectional, observational study analysed data from 19 women (33.0±3.9 years) nursing 1–6-month-old infants and with previous breast milk expression experience. Breast milk was weighed continuously during a 15-min single-breast electric pumping session. The HFP features and flow rate time (≥0.1 g/s) were analysed to determine each individual's milk flow pattern. The total expressed breast milk was 69.8±42.5 g with a maximum individual flow rate of 0.5±0.2 g/s. The breast milk yielded during the HFPs was 43.1 (34.4–81.3) g, accounting for 82.5% (69.9–89.5%) of the total expressed breast milk. HFP occurred 0–3 times during the 15 min session. Multiple discrete and continuous milk flow patterns were observed. Among those with discrete HFP, the HFP interval was 221 (68–371) s. Breast milk fat content changes and subjective residual milk measurements implied sufficient milk removal. Individual differences in milk flow pattern were observed among the women using HFP. Milk flow patterns were consistent with previous reports. Milk flow pattern data can be used to guide individualised lactation support.