Effect of Feeding Fresh or Frozen Breast Milk on the Gut Microbiota of Premature Infants: A Prospective Observational Study

Abstract

Background Breast milk is essential for premature infants. It contains a variety of functional and protective nutrients that help to create a suitable microenvironment for intestinal development and maturation. This prospective and observational study was planned to examine the effects of feeding premature infants with fresh or frozen breastmilk on their gut microbiota. Materials and Methods The study was carried out with a total of 40 infants, with a gestational age of 28–326 weeks, fed fresh ( n = 20) or frozen ( n = 20) breastmilk. Stool samples were stored at −80°C until analysis. Infants were included in groups based on the feed type, which accounted for more than 70% of their 10-day feeding. The Mann-Whitney U, Chi-square, and t-tests were used to evaluate the demographic data. Stool samples were analyzed by sequencing the V3–-V4 region of the 16S rRNA gene from the extracted DNA for microbiota analysis. Results Streptococcus and Enterobacteriales, the majority of which are considered human pathogens, in infants receiving frozen breastmilk ( Streptococcus 69%, Enterobacteriales 79%) was higher than that in infants receiving fresh breastmilk ( Streptococcus 16%, Enterobacteriales 49%). Further, the Lactobacillus and Bifidobacterium species were more abundant in infants who received fresh breastmilk ( Lactobacillus 17%, Bifidobacterium 12%) than in infants who received frozen breastmilk ( Lactobacillus 3%, Bifidobacterium 1%). Conclusion Thus, compared to frozen breast milk, fresh breastmilk has an effect on the diversity of preterm infants’ gut microbiota.

The Maternal Diet Index and Offspring Microbiota at 1 Month of Life: Insights from the Mediterranean Birth Cohort MAMI

“…In terms of species of importance in the early infant gut microbiome, Bifidobacterium members dominate in the microbiome of breastfed and vaginally born infants. Merter et al [ 15 ] and others [ 14 ] also described an abundance of Lactobacillus and Streptococcus in breastfed infants. Low microbial diversity and the predominance of Bifidobacterium members are considered characteristic traits of early microbiota composition [ 15 ].…”

“…Merter et al [ 15 ] and others [ 14 ] also described an abundance of Lactobacillus and Streptococcus in breastfed infants. Low microbial diversity and the predominance of Bifidobacterium members are considered characteristic traits of early microbiota composition [ 15 ]. The Bifidobacterium species in infants is considered to promote the maturation of the healthy immune system.…”

“…“Lower” MDI-med scores were also associated with increased numbers of E.coli , Shigella , Enterococcus , Clostridium sensu stricto 1 , and Veillonella . Many of these bacteria are often found in fecal samples of formula-fed infants [ 14 , 15 ]. Lundgren et al [ 21 ] reported an association between increased fruit intake and increased odds of increased Streptococcus/Clostridium among infants who were 6 weeks of age and born vaginally.…”

“…The initial adjusted model (model 1) included the mode of birth and antibiotic exposure. An additional adjusted model was built (model 2), which included breastfeeding type at 1 month of age (breastmilk, formula, or mixed) and maternal gestational antibiotic use, as these have been associated with microbial diversity in some studies [ 14 , 15 , 16 ]. The final models report, where appropriate, beta estimates, p -values, and 95% confidence intervals for the associations.…”

Probiotics: Bridging the interplay of a healthy gut and psychoneurological well‐being

“…These indigestible carbohydrates are believed to serve as a primary source of sustenance for bacterial fermentation. When provided to premature infants, breast milk fosters an environment conducive to the proliferation of beneficial species, such as Bifidobacterium, counteracting the dominance of proteobacteria observed in premature infants with an atypical bacterial composition (Merter & Altay, 2023; Salli et al, 2023).…”