Importance of Milk Expression for Preterm Infants

Mothers of preterm infants may find it difficult to express breast milk. There is a low breast milk rate among preterm infants at discharge at our hospital, and here we tested the hypothesis that milk expression factors were the cause of the low rate. The study subjects were born before 33 gestational weeks at our hospital between March 2005 and June 2014. Nutritional evaluation was performed at discharge and noted whether breast milk, infant formula, or a mix of the 2 was being given. We compared the group given breast milk or the mix versus the group given formula. Of the 337 infants, 40 cases were excluded. Data from 297 infants were analyzed. The mean (SD) gestational age and birth weight were 29.5 (2.4) weeks and 1,230 (391) g, respectively. At discharge, 26 (8.8%), 102 (33.3%), and 174 (57.9%) infants were given breast milk, formula, and the mix, respectively. A multivariate logistic regression analysis showed that the first milk expression (h) was the risk factor for the formula group: adjusted odds ratio (95% confidence interval) 1.06 (1.02-1.09) and p=0.002. Delayed first milk expression could affect the low breast milk rate at discharge. Improvement of milk expression should be achieved to promote breastfeeding.