Impact of Access to Pasteurised Donor Human Milk on Rates of Necrotising Enterocolitis in Neonatal Units in Australia: A Cohort Study

BACKGROUND AND AIM: In 2018, a pasteurised donor human milk (PDHM) service was established within Australia's national blood service, Lifeblood, and subsequently expanded to a national service. Before 2018, five milk banks operated in Australia, but most infants admitted to Australian neonatal intensive care units (NICUs) still did not have access to PDHM. This study aimed to compare infant outcomes before and after Australian NICUs had access to an assured supply of PDHM from Lifeblood. METHODS: Cohort study utilising Australian and New Zealand Neonatal Network data for infants born < 32 weeks' gestation admitted to 15 NICUs across Australia over a 3-year period (2018-2020; n = 4395 infants). The primary study factor was NICU access to an assured supply of PDHM from Lifeblood. Neonatal outcomes were compared in periods with "PDHM available" versus "PDHM not available". The primary outcome was the proportion of infants born < 28 weeks' gestation who developed NEC. Secondary outcomes included duration of parenteral nutrition, retinopathy of prematurity, infection, death, length of stay, weight at discharge, and breast milk feeding at discharge. RESULTS: After adjusting for confounding risks, NEC relative risk was 38% lower for infants born < 28 weeks' (aRR 0.62, 95% CI 0.46-0.83) when Lifeblood PDHM was available. Weight at discharge (2828.8 vs. 2939.56 g, p = 0.001) was lower when PDHM was available. Breast milk feeding at discharge, infections and death were not associated with PDHM availability. CONCLUSIONS: Reliable access to PDHM was associated with reduced risk of NEC for infants born < 28 weeks' gestation in Australian NICUs.