Early and exclusive enteral nutrition in infants born very preterm.

Objective: To characterise the effects of early and exclusive enteral nutrition with either maternal or donor milk in infants born very preterm (28^0/7-32^6/7 weeks of gestation).

Design: Parallel-group, unmasked randomised controlled trial.

Setting: Regional, tertiary neonatal intensive care unit.

Participants: 102 infants born very preterm between 2021 and 2022 (51 in each group).

Intervention: Infants randomised to the intervention group received 60-80 mL/kg/day within the first 36 hours after birth. Infants randomised to the control group received 20-30 mL/kg/day (standard trophic feeding volumes).

Main outcome measures: The primary outcome was the number of full enteral feeding days (>150 mL/kg/day) in the first 28 days after birth. Secondary outcomes included growth and body composition at the end of the first two postnatal weeks, and length of hospitalisation.

Results: The mean birth weight was 1477 g (SD: 334). Half of the infants were male, and 44% were black. Early and exclusive enteral nutrition increased the number of full enteral feeding days (+2; 0-2 days; p=0.004), the fat-free mass-for-age z-scores at postnatal day 14 (+0.5; 0.1-1.0; p=0.02) and the length-for-age z-scores at the time of hospital discharge (+0.6; 0.2-1.0; p=0.002). Hospitalisation costs differed between groups (mean difference favouring the intervention group: -$28 754; -$647 to -$56 861; p=0.04).

Conclusions: In infants born very preterm, early and exclusive enteral nutrition increases the number of full enteral feeding days. This feeding practice may also improve fat-free mass accretion, increase length and reduce hospitalisation costs.

Trial registration number: NCT04337710.