Long Duration of Oral Care Using Mother’s Own Milk Influences Oral Microbiota and Clinical Outcomes in Very-low-birthweight Infants: Randomized Controlled Trial

Abstract

Background: Several studies have focused on the clinical outcomes of oral care using colostrum for a limited time (2–5 days) in very-low-birthweight (VLBW) infants. However, the effect of long-term mother’s own milk (MOM) on the clinical outcomes and oral microbiota of VLBW infants remains unknown. Methods: In this randomized controlled trial, VLBW neonates were randomly assigned to oral care by MOM or sterile water (SW) groups until they started oral feeding. The primary outcome was oral microbiota composition including alpha and beta diversity, relative abundance, and linear discriminant analysis effect size (LEfSe). The secondary outcomes were various morbidities and mortality. Results: The baseline characteristics of the two groups did not differ (63 neonates, MOM group, n = 30, oral care 22 days; SW group, n = 33, oral care 27 days). There was no significant difference in alpha and beta diversities between the groups before and after the intervention. The MOM group had a significantly lower rate of clinical sepsis than the SW group (47% vs. 76%, risk ratio = 0.62, 95% CI: 0.40−0.97). The relative abundance of Bifidobacterium bifidum and Faecalibacterium were maintained after MOM care, especially in neonates without clinical sepsis, but decreased after SW care. LEfSe showed that neonates in the MOM and SW groups with clinical sepsis had the highest abundance of Pseudomonas and Gammaproteobacteria, respectively, compared with neonates without sepsis. Conclusions: A longer duration of oral care using MOM in VLBW infants sustains healthy bacteria and decreases the risk of clinical sepsis.