Objective: To determine the effect of timing of expression initiation on mother's own milk production and time to secretory activation in mothers of preterm infants.
Study design: 180 mothers delivering infants ≤1500 grams and ≤32 weeks gestation were randomized to begin expression within 60 (early), 61-180 (intermediate) or 181-360 (late) minutes following delivery. Milk volume was measured on days 1-7 and weekly for 6 weeks. Time to secretory activation was determined through self-report.
Results: The late group produced more milk than the early group in the first 3 days (p = 0.015-0.031) and over 6 weeks (p = 0.045). The late group had more expressions on day 1 (early: p = 0.049; intermediate; p = 0.048).
Conclusion: Initiation of expression at 181-360 min following delivery was associated with increased milk production for 6 weeks following delivery. Further research is needed to determine the effect of expression frequency on milk production in the first days following birth.