Volume of foremilk, hindmilk, and total milk produced by mothers of very preterm infants born at less than 28 weeks of gestation.

The purpose of this study is to describe foremilk volume (milk produced in the first 3 minutes of pumping), hindmilk volume (remainder of milk produced), and total milk volume produced by mothers of very preterm infants at 3 weeks postpartum and associated factors. Mothers (n = 24) mechanically pump their breasts a median (minimum, maximum) of 7 times (5, 9 times) per 24 hours for a total of 15 minutes (9.4, 23.9 minutes) each time. Foremilk, hindmilk, and total milk volumes are 183 mL per 24 hours (80, 810), 318 mL per 24 hours (98, 1007), and 545 mL per 24 hours (224, 1817), respectively. Milk volumes are not associated with mother's age, race or ethnic background, education, parity, reported prepregnancy body mass index, previous breastfeeding experience, frequency of milk pumping, longest time between pumps, infant birth weight, or multiple births. The degree of pre-maturity (<26 weeks vs 26(0/7)-27(6/7) weeks) is significantly related to the relative proportion of foremilk/hindmilk volumes (45:55 vs 36:65, respectively).