The goal of this post-market study is to describe the effect of a liquid supplement containing 2 specific human milk oligosaccharides (HMOs), 2'-fucosyllactose [2'FL] and lacto-N-neotetraose [LNnT], on feeding tolerance, growth, and adverse events of special interest in preterm infants in a real-world setting.

A comparison with data collected retrospectively from a historical group at each site will be made for time to reach full enteral feeding, growth and adverse events. Infants in the historical group were not exposed to an HMO supplement but followed the same local nutrition protocol to avoid confounding by differences in clinical or feeding practice.

Inclusion Criteria:

1. Written informed consent has been obtained from at least one parent (or other legally acceptable representative [LAR], if applicable)
2. Infant's parent(s)/LAR is of legal age of majority, has parental authority, must understand the consent form and other relevant study documents, and is willing and able to fulfil the requirements of the study protocol
3. Infant gestational age is ≤ 34 weeks as determined by the first day of the mother's last menstrual period or by fetal ultrasound
4. Infant birth weight ≤ 2500g
5. Infant postnatal age ≤ 14 days
6. Infant has tolerated trophic feeds (e.g., 10-15 mL/kg/day) for at least 24 hours but has not yet reached full enteral feeding

Exclusion Criteria:

1. Infant is clinically unstable, for example:

   1. Infant has hemodynamic instability as evidenced by clinical signs of sepsis, hypotension (MAP < 5th percentile for age for at least three hours), or is receiving vasopressor drugs
   2. Infant has received an exchange transfusion within the past 48 hours
   3. Infant has had an episode of severe asphyxia at birth (PH less than 7.0)
   4. Infant has signs of necrotizing enterocolitis according to modified Bell staging criteria (stage IIA or higher)

2. Major congenital (e.g., heart disease, skeletal dysplasia, chondrodystrophy, gastrointestinal obstruction or atresia) or chromosomal abnormality (e.g., trisomy 21, Turner syndrome)

3. Infant has other medical condition that, in the judgement of the investigator, would make the child inappropriate for entry into the study

4. Participation in another interventional clinical study that may interfere with the results of this study