Characterization of the Gastrointestinal Microbiota in Newborn Infants

Inclusion Criteria: * Inclusion Criteria for the pregnant person: 1. Healthy pregnant person in gestational week 36+0-38+0 2. Age ≥ 18 years 3. Normal singleton pregnancy 4. Ability to read and speak Danish 5. Normal ultrasound scan of the fetus at gestational age 19-20 weeks 6. Plan to exclusively breastfeed 7. Provided voluntary written informed consent. * Inclusions Criteria for the newborn: 1. Born at full-term ≥37+0 2. Birth weight above 2500 g 3. APGAR score of at least 7 within the first 5 min of life. Exclusion Criteria: * Exclusion Criteria for the pregnant person: 1. Pregnancy at over 38+0 weeks' gestation at recruitment 2. Multiple pregnancy 3. Pregnancy with any fetal abnormality 4. Alcohol or drug abuse 5. Plan to give birth at other hospitals than Copenhagen University Hospital Hvidovre 6. Any contraindications for breastfeeding. Exclusion Criteria for the newborn : 1. Congenital disorders that could affect their safety or the study outcome 2. Admission to Neonatal Intensive Care Unit for more than 24 hours 3. Participation in another clinical intervention study which can interfere with this probiotic intervention 4. No other probiotics than the study product.