One million premature babies die due to prematurity complications, contributing the most to the causes of death in children under 5 years old. Indonesia ranks 5th among countries with the highest premature birth rates in the world, with a mortality rate of 11.1% of all live births, making it the leading cause of neonatal deaths (63.5%). Compared to full-term babies, premature infants are more often born through cesarean section (SC), have an immature immune system, receive antibiotics, and also receive care in the Neonatal Intensive Care Unit (NICU). This can disrupt the formation of gut microbiota early in life. The abnormal bacterial colonization pattern in the intestines of premature infants is dominated by potentially pathogenic microbiota such as Staphylococcus, Klebsiella, Escherichia, and Clostridium. These changes in the gut microbiota ecosystem further increase the risk of severe morbidity during treatment in the NICU, such as necrotizing enterocolitis (NEC), late-onset sepsis (LOS), and long-term morbidities such as asthma and eczema. For decades, probiotics have been researched as non-pathogenic microorganisms that, when given in appropriate amounts, can provide benefits to humans. The results of the research indicate that the administration of probiotics can reduce the incidence of dysbiosis or the imbalance between commensal microbiota and intestinal pathogenic microbiota, strengthen the intestinal barrier, prevent enteropathogenic infections, suppress antimicrobial resistance, increase the body's immunity, and maintain intestinal motility. Based on this mechanism, probiotics are considered to improve outcomes for neonates, especially premature babies. This study was conducted thoroughly through metagenomic and metabolomic analyses of the intestinal microbiota, thereby providing information on the effectiveness of triple strain Bifidobacterium probiotic supplementation based on the abundance of pathogenic and commensal microbiota, alpha and beta diversity, and SCFA levels in the feces of premature infants. The study sample included all accessible populations that met the inclusion criteria. Subjects were randomly divided into two groups: one receiving probiotics and the other not receiving probiotics. Baseline data were collected for all subjects, including their characteristics, anthropometric data, and the antibiotic and probiotic history of mothers and infants. Subsequently, samples were taken from the infants three times, specifically on the first three days (T1), two weeks after probiotic administration (T2), and three weeks after probiotic administration (T3); these samples were then sent to the laboratory for microbiome and metabolomic analysis. The targeted output of this study is the publication of a scientific article in an international journal indexed by Scopus on the analysis of the effect of probiotic administration on metagenomic and metabolomics of the intestinal microbiota of sick premature infants in the NICU. Research on the effectiveness of the triple strain of Bifidobacterium probiotics (Bifidobacterium breve M-16V, Bifidobacterium longum subsp. infantis M-63 and Bifidobacterium longum subsp. longum BB536) in premature infants has never been conducted in South Sulawesi or even in Indonesia. Although research on the effectiveness of the triple strain of Bifidobacterium has been carried out in Japan and Australia, the geographical and ethnic influence on the microbiome pattern is the basis for the need to continue research in Indonesia. So this is certainly a novel value and the results are expected to provide an overview of the microbiome pattern of premature babies in Makassar in particular and in Indonesia in general. In addition, the results of this study can also be the basis for new recommendations regarding the administration of probiotics as an adjunct therapy in the management of premature infants in the NICU.

Inclusion Criteria:

• Premature infants (gestational age 28 to <34 weeks) treated in the NICU with a birth weight of 1000 to <2500 grams
• No contraindications to giving the drink in the first 3 days of life
• Parents agree to participate in the study and sign a consent letter.

Exclusion Criteria:

• Major congenital disorders
• Severe sepsis
• No stool production in the first 3 days of life
• Received formula milk that contains probiotics

The participant's data will be kept secret to protect the privacy of the participants.

This study is single-blinded study where the subjects doesn't know if they are included in intervention or comtrol group.