Using Donor Human Milk in Very Low Birth Weight Infants
TalkingNutrition has written before on the topic of donor human milk for healthy, term infants. Now, a study from Kantorowska and co-workers has been published looking at the effect of introducing a donor milk program for very low birth weight (VLBW) infants. VLBW infants are defined as having a birth weight of less than 1500 g and make up 1.4% of births in the US, or around 20 million births worldwide. The most common cause of low birth weight is preterm birth, and VLBW is generally seen in infants born before 30 weeks of gestation, although intrauterine growth restriction is also a cause.
The diet of a premature infant is different to a term infant, as it has to attempt to provide the nutrients normally transferred across the placenta during pregnancy. VLBW infants are particularly difficult to feed as their gastrointestinal system is immature and they may not be able to tolerate the volumes of milk that would be needed to meet their nutrient needs. Intravenous nutrient solutions are often used initially, with the amount of milk gradually increased over the first weeks.
Over the past 100 years we appear to have come back to where we started with the type of milk used in premature infants. At the turn of the century, as Greer summarizes in a fascinating historical article, breast milk was seen as the best option for feeding these “weaklings”. As preterm births can often be the result of serious health conditions in the mother, as was the case with two friends of mine who developed eclampsia during their pregnancy and were not able to breast feed, wet nurses were able to provide breast milk for premature infants if the mother was not able. By the 1940s, it was known that normal breast milk did not contain enough protein, minerals and vitamins to enable the infant to grow at the same rate as it would have inside the womb. Formulas were developed in the 1980s specially for preterm infants, and weight gain of VLBW infants was found to be a little better than those fed breast milk. Human milk fortifiers that contained the extra nutrients could also be added to breast milk so that it could better meet the needs of preterm infants. In the 1990s, human milk (with or without fortifiers) was again being recommended to help prevent the dreaded, life-threatening disease necrotizing enterocolitis, in which part of the tissue of the small or large intestine becomes damaged and starts to die off, potentially causing intestinal contents to leak into the bowel cavity. Although the risk varies with prematurity, rates are around 5% of VLBW infants (see Ahle, Drott and Andersen).
However, the evidence base for choosing infant formula or breast milk is not unequivocal. A Cochrane review from April 2014 found that the evidence base was limited, but that the rate of necrotizing enterocolitis was 2-3 times higher when infant formula was used compared to donor breast milk. There were no trials of formula compared to maternal breast milk. Some groups have found that the use of breast milk translates to lower newborn intensive care unit costs (Assad), whereas others have found no significant differents (Parker).
The article by Kantorowska described whether donor human milk availability affected rates of necrotizing enterocololitis in Californian newborn intensive care units. Donor human milk has become more widely available in California over the past ten years, through organizations such as the Human Milk Banking Association of North America. The authors were able to link patient level data collected as the California Perinatal Quality Care Collaborative with the availability of human donor milk at hospitals. They found that 22 hospitals showed a clear transition to using donor milk (presumably the transition resulted in a reduction in the use of infant formula) over the study period.
The authors found that the rate of necrotizing enterocolitis was reduced by 2.5% in the hospitals that could provide donor human milk. Rates of any breastfeeding at discharge were also increased by 10% in these hospitals. This study reinforces that human breast milk is the “optimal way of feeding infants”. Donor human milk can help the most vulnerable VLBW infants.
Agata Kantorowska, Julia C. Wei, Ronald S. Cohen, Ruth A. Lawrence, Jeffrey B. Gould, Henry C. Lee. Impact of Donor Milk Availability on Breast Milk Use and Necrotizing Enterocolitis Rates. Pediatrics March 2016. http://dx.doi.org/10.1542/peds.2015-3123
Assad M, Elliott MJ, Abraham JH. Decreased cost and improved feeding tolerance in VLBW infants fed an exclusive human milk diet. J Perinatol. 2015 Nov 12. doi: 10.1038/jp.2015.168. [Epub ahead of print] http://www.ncbi.nlm.nih.gov/pubmed/26562370
DSM Corporate Public Affairs. DSM Position on Infant Formula. April 2013. http://www.dsm.com/content/dam/dsm/cworld/en_US/documents/dsm-position-paper-infant-formula.pdf
Frank R. Greer. Feeding the Premature Infant in the 20th Century. J. Nutr. 2001 131: 2 426S-430S. http://jn.nutrition.org/content/131/2/426S.full
Parker LA, Krueger C, Sullivan S, Kelechi T, Mueller M. Effect of breast milk on hospital costs and length of stay among very low-birth-weight infants in the NICU. Adv Neonatal Care. 2012 Aug;12(4):254-9. doi: 10.1097/ANC.0b013e318260921a. http://www.ncbi.nlm.nih.gov/pubmed/22864006
Quigley M, McGuire W. Formula milk versus donor breast milk for feeding preterm or low birth weight infants. 22 April 2014 http://www.cochrane.org/CD002971/NEONATAL_formula-milk-versus-donor-breast-milk-for-feeding-preterm-or-low-birth-weight-infants