Human breast milk is the best food for human babies. Although the evidence for some of the benefits is not as sound as I would like, I think it is clear that the benefits for preterm infants are substantial. Hence the growth in human milk banks, which are now supposed to be run according to standards which are similar to those for blood product banking (which makes the milk much more expensive than in the olden days). One possible risk of having such banks is that it might reduce the use of mothers own milk.
Two recent publications are reassuring; (Delfosse NM, Ward L, Lagomarcino AJ, Auer C, Smith C, Meinzen-Derr J, Valentine C, Schibler KR, Morrow AL: Donor human milk largely replaces formula-feeding of preterm infants in two urban hospitals. J Perinatol 2012.) 2 Hospitals in Cincinnati introduced a program to supply donor milk in 206, and progressively over the subsequent years, as donor milk increased, there was much less formula used, but no apparent effect on breast milk use.
The other is an observational study from a number of Italian NICUs, some of them had Human milk banks, and others did not; (Arslanoglu S, Moro GE, Bellu R, Turoli D, De Nisi G, Tonetto P, Bertino E: Presence of human milk bank is associated with elevated rate of exclusive breastfeeding in vlbw infants. J Perinat Med 2012:1-3). . Exclusive breastfeeding rate at discharge of very low birth weight infants was significantly higher in NICUs with a milk bank than in NICUs without (29.6% vs. 16.0%, respectively). Any breastfeeding at discharge was 60.4% vs. 52.8%, P=0.09. These are not very impressive rates, but they at least don’t suggest an adverse influence of having a breast milk bank.