Initiation and frequency of pumping and milk production in mothers of non-nursing preterm infants.

This secondary data analysis examined if time of initiation of milk expression and pumping frequency influenced milk weight weeks 2-5 postpartum. Of the 39 subjects in the convenience sample, 20 were in the early initiating (EI) group, (n = 12 high frequency [HF], n = 8 low frequency [LF]), and 19 were in the late intiating (LI) group, (n = 7 HF, n = 12 LF). The EI group initiated pumping < or = 48 hours after birth; the HF group pumped a minimum of 6.25 times daily. A two-way analysis of variance indicated that milk weight was significantly higher in the HF as compared to the LF group. While there was no significant difference in milk weight between the EI and LI groups, there was a significant interaction between frequency and initiation. Milk weight for the LF/EI group appeared to be positively influenced by the initiation of mechanical expression soon after birth.