An interventional, randomized, double-blind, placebo-controlled study will be conducted to investigate the effect of a new probiotic strain Lactobacillus PS11603 & Bifidobacterium PS10402 in premature infants from 28 weeks + 0 days to 30 weeks + 6 days of gestation.

The study duration will be 2 months, which includes 8 weeks product administration. Participants will be randomized assigned to one of the two study groups: the control group with placebo consumption and a probiotic consumption group.

An interventional, randomized, double-blind, placebo-controlled study will be conducted to investigate the effect of a new probiotic strains Lactobacillus PS11603 & Bifidobacterium PS10402 in 30 premature infants born within 28 weeks + 0 days to 30 weeks + 6 days of gestation.

The duration of participation in the study is estimated to be 40-60 days. Participants will be randomized assigned to one of the two arms of the study: the control group, with placebo consumption, and a probiotic consumption group. The aim of the study will be investigate the effect of the probiotics strains in the colonization of the intestinal tract of preterm babies.

Inclusion Criteria:

• Preterm infants born between week 28 + 0 days and week 30 + 6 days of gestation.
• Written informed consent signed by the parent or legal guardian.
• Tolerate enteral feeding, at least 10mL / kg / day.
• Postnatal age ≤ 5 days

Exclusion Criteria:

• Child with malformations
• With short bowel syndrome or any surgery in the gastrointestinal tract
• With defect in the intestinal epithelial barrier