Lactobacillus Reuteri DSM 17938 in Gut Microbiota Development in Infant Born by Caesarean Section

This is a single‐center prospective randomized double‐blind placebo‐controlled clinical study. The planned duration of the study for each included infant will be 16 weeks, 4 weeks of study drug intake and 12 weeks of follow‐up. 140 healthy infants born by Caesarean section will be included in the general group of the study, and 60 healthy infants born by natural vaginal delivery will be included in the control group. For infants included in the control group, all the same protocol requirements and procedures will be applied as for infants in the general group, except for randomization and the study product / placebo intake. Infants included in the general study group will be randomly assigned into the study product / placebo subgroups in 1: 1 ratio. During the study the gut microbiota will be analyzed. Feces samples should be collected no later than 72 hours after birth, and also on 14th day of life ± 3 days, 30th day of life ± 3 days and 112th day of life ± 3 days. Short‐chain fatty acids (SCFA) will be analyzed in feces samples.