Preterm infants commonly experience feeding intolerance, which can delay advancement of enteral feeding and impair early growth. This randomized double-blind controlled trial evaluated whether lactase enzyme supplementation could improve feeding tolerance and growth in Egyptian preterm infants born before 34 weeks of gestation. Infants were assigned to receive either feeds supplemented with lactase enzyme or standard feeds without lactase for 2 weeks from the start of enteral feeding. The study hypothesized that lactase supplementation would reduce signs of feeding intolerance and improve weight gain. Outcomes included feeding intolerance symptoms, stool markers of carbohydrate malabsorption, feeding progression, growth parameters, and selected clinical outcomes including necrotizing enterocolitis.

Inclusion Criteria:

• Preterm infants born before 34 weeks of gestation
• Infants prescribed to start enteral feeding
• Absence of gastrointestinal disorders at enrollment, including necrotizing enterocolitis

Exclusion Criteria:

• Congenital heart disease
• Other serious congenital malformations
• Cow's milk protein allergy symptoms such as abdominal distension or increased exhaust
• Diagnosed necrotizing enterocolitis
• Neonatal sepsis
• Legal guardian unwilling to provide informed consent

De-identified individual participant data underlying the results reported in this study, including demographic characteristics, feeding tolerance assessments, growth parameters, laboratory results, and clinical outcomes, will be made available to qualified researchers upon reasonable request after publication of the main study results. Shared data will exclude direct identifiers and will be released in a de-identified format in accordance with institutional and ethical requirements.

Data will be available beginning 6 months after publication of the primary manuscript and for up to 5 years thereafter.

Access will be provided to qualified researchers whose proposed use of the data has been approved by the principal investigator and the relevant institutional authority. Data requestors may be required to submit a methodologically sound proposal and sign a data access or data use agreement.

This was a prospective double-blind controlled trial. Randomization codes were generated by a person not directly involved in the study. Feeding bottles were prepared and labeled using coded assignment to maintain blinding. Parents, study investigators, and outcome assessors were blinded to treatment allocation throughout the study period.