A survey of practices in Germany, Austria, and Switzerland (the German speaking part) demonstrates the range of practices for handling mother’s own breast milk in very preterm babies. Klotz D, et al. Handling of Breast Milk by Neonatal Units: Large Differences in Current Practices and Beliefs. Front Pediatr. 2018;6:235.

The authors wanted to know what the units did for CMV surveillance and inactivation, bacterial cultures and responses to cultures, and how they managed fortification. About half of the 300 or so units replied.

Most units performed some sort of maternal CMV screening, but 66% fed raw colostrum from sero-positive mothers for at least a couple of days. After that 58% performed some sort of CMV inactivation for milk from sero-positive mothers, either standard Holder pasteurization, high temperature short duration pasteurization, or freezing and thawing the milk, usually until about 32 weeks.

Nearly half of the units cultured the breast milk, and then either pasteurized it or threw it out based on bacteria found and bacterial counts; there were 30 different thresholds for those actions in the different units.

Fortification was individualized using breast milk analysis in only 16 units (5 of those in a trial, only 6 did it as a routine, the remainder in selected cases). Fortification was usually with commercial multi-component fortifiers, but additional use of protein was common, additional lipids and carbohydrates were also sometimes used.

Units started putting babies to the breast mostly at 32 weeks, sometimes at 33 or 34 weeks.

Practices in different parts of the world might well be very different to those in this survey, but the study pointed out to me how little we know about what we should really do about these issues. In some countries the national recommendation is to pasteurize all maternal breast milk before giving it to the most immature babies. Pasteurization inactivates CMV, and profoundly decreases bacterial counts, but has negative effects on several large proteins, including some of those which may be responsible for the advantages of maternal breast milk. Two trials comparing raw mothers milk to pasteurized mother’s milk (Stock K, et al. Pasteurization of breastmilk decreases the rate of postnatally acquired cytomegalovirus infections, but shows a nonsignificant trend to an increased rate of necrotizing enterocolitis in very preterm infants–a preliminary study. Breastfeeding medicine. 2015;10(2):113-7. A “before and after” study and Cossey V, et al. Pasteurization of Mother’s Own Milk for Preterm Infants Does Not Reduce the Incidence of Late-Onset Sepsis. Neonatology. 2012;103(3):170-6, a Randomized Controlled Trial) both show a trend to more complications if mothers’ breast milk is pasteurized.

Using mother’s own milk is an important factor in improving outcomes for very preterm babies, I think it is about time we knew how to do it.

What are the indications for pasteurizing mother’s own milk? How is it best done to be effective and have the fewest adverse impacts? For which babies do we need to adjust fortification, and is individual breast milk analysis significantly better than just adding more protein (or protein and fat, or…)? Does adding prebiotics improve outcomes? How can we normalize the development of the intestinal microbiome in addition to mother’s milk?

And,just as important:

How can we increase the percentage of mothers who commence breast milk production for their very preterm baby? How can we increase breast milk production over the long term? How can we increase the proportion of babies who go home receiving exclusively mother’s milk?

There are, fortunately, now many investigators around the world researching some of these issues (you can see a list of a selection of recent publications below; sorry I haven’t got time to put a URL attached to each one, but they are all listed in PubMed), but many important questions remain to be answered.

Parker LA, et al. Facilitating Early Breast Milk Expression in Mothers of Very Low Birth Weight Infants. MCN Am J Matern Child Nurs. 2018;43(2):105-10.
Romaine A, et al. Predictors of Prolonged Breast Milk Provision to Very Low Birth Weight Infants. The Journal of pediatrics. 2018.
Cuttini M, et al. Breastfeeding outcomes in European NICUs: impact of parental visiting policies. Archives of disease in childhood Fetal and neonatal edition. 2018.
Tshamala D, et al. Factors associated with infants receiving their mother’s own breast milk on discharge from hospital in a unit where pasteurised donor human milk is available. J Paediatr Child Health. 2018;54(9):1016-22.
Grzeskowiak LE, et al. Domperidone for increasing breast milk volume in mothers expressing breast milk for their preterm infants: a systematic review and meta-analysis. BJOG : an international journal of obstetrics and gynaecology. 2018;0(0).
Haiden N, et al. Comparison of bacterial counts in expressed breast milk following standard or strict infection control regimens in neonatal intensive care units: compliance of mothers does matter. J Hosp Infect. 2016;92(3):226-8.
Hannan KE, et al. Impact of NICU admission on Colorado-born late preterm infants: breastfeeding initiation, continuation and in-hospital breastfeeding practices. J Perinatol. 2018.
Kaya V, Aytekin A. Effects of pacifier use on transition to full breastfeeding and sucking skills in preterm infants: a randomised controlled trial. J Clin Nurs. 2017;26(13-14):2055-63.
Pannaraj PS, et al. Association Between Breast Milk Bacterial Communities and Establishment and Development of the Infant Gut Microbiome. JAMA Pediatr. 2017.
Heon M, et al. An Intervention to Promote Breast Milk Production in Mothers of Preterm Infants. West J Nurs Res. 2016;38(5):529-52.
Tully KP, et al. A Test of Kangaroo Care on Preterm Infant Breastfeeding. Journal of Obstetric, Gynecologic & Neonatal Nursing. 2016;45(1):45-61.
Peters MD, et al. Safe management of expressed breast milk: A systematic review. Women Birth. 2016;29(6):473-81.
da Cunha RDeS, et al. Breast milk supplementation and preterm infant development after hospital discharge: a randomized clinical trial. Jornal de Pediatria. 2016;92(2):136-42.
Belfort MB, et al. Breast Milk Feeding, Brain Development, and Neurocognitive Outcomes: A 7-Year Longitudinal Study in Infants Born at Less Than 30 Weeks’ Gestation. The Journal of pediatrics. 2016.
Kreissl A, et al. Human Milk Analyser shows that the lactation period affects protein levels in preterm breastmilk. Acta Paediatr. 2016;105(6):635-40.
Healy DB, et al. Structured promotion of breastmilk expression is associated with shortened hospitalisation for very preterm infants. Acta Paediatr. 2016;105(6):e252-6.
Post ED, et al. Milk production after preterm, late preterm and term delivery; effects of different breast pump suction patterns. J Perinatol. 2015.
Mörelius E, et al. A randomised trial of continuous skin-to-skin contact after preterm birth and the effects on salivary cortisol, parental stress, depression, and breastfeeding. Early Human Development. 2015;91(1):63-70.