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

Problem: Breast pumping practices have scope for improvement.

Background: Breast milk weight measurement can be used to evaluate milk flow pattern dynamics during breast pumping.

Aim: 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.

Methods: 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.

Findings: 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. A strong positive correlation was noted between HFP length and total breast milk expression volume.

Discussion: Individual differences in milk flow patterns were observed among the women using HFP. Milk flow patterns were consistent with previous reports.

Conclusion: Milk flow pattern data can be used to guide individualised lactation support.