Pasteurization of Mother’s Own Milk for Preterm Infants Does Not Reduce the Incidence of Late-Onset Sepsis

Abstract

Background: Feeding preterm infants human milk has a beneficial effect on the risk of late-onset sepsis (LOS). Due to lack of microbiological standards, practices such as pasteurization of mother’s own milk differ widely among neonatal intensive care units worldwide. Objectives: To investigate whether pasteurization of mother’s own milk for very-low-birth-weight (VLBW) infants influences the incidence and severity of infection-related outcomes. Methods: In this randomized controlled trial, preterm infants (gestational age <32 weeks and/or birth weight <1,500 g) received either raw or pasteurized mother’s own milk during the first 8 weeks of life. The primary outcome was the incidence of proven LOS. A dose-response relation was verified, i.e. the dependence of the risk of sepsis on the actual and cumulative quantities of mother’s own milk. Results: This study included 303 VLBW infants (mean birth weight: 1,276 g; mean gestational age: 29 weeks) whose baseline and nutritional characteristics were similar. The incidence of laboratory-confirmed sepsis was not statistically different in infants fed raw milk compared to infants who received pasteurized milk: 22/151 (0.15, CI: 0.08–0.20) and 31/152 (0.20, CI: 0.14–0.27), respectively (RR: 0.71; 95% CI: 0.43–1.17). A significant dose-response relation was observed between the adjusted quantity of enteral feeding and the risk of LOS, regardless of the type of feeding. Conclusion: For preterm infants, pasteurization of mother’s own milk shows a trend towards an increase in infectious morbidity, although no statistical significance was reached. Practices should focus on collection, storage and labeling procedures to ensure the safety and quality of expressed milk.