Infants admitted to Danish neonatal units demonstrate satisfactory growth independent of feeding type at discharge.

Aim: The aim was to investigate feeding type at discharge; exclusively breastfeeding (EBF), mixed breastfeeding (MBF), and formula milk feeding (FMF), factors associated with feeding type, and changes in weight-for-age z-score (ΔWAZ) in infants admitted to Danish neonatal units.

Methods: Using data from the Danish National Quality Database for Births and the Danish Newborn Quality Database, we included 8639 mother-infant dyads admitted ≥5 days between February 2019 and December 2021. We used logistic regression to investigate associations between maternal and infant factors and feeding type, and descriptive statistics to describe ΔWAZ and feeding type at discharge.

Results: Of all infants 59.1% were EBF, 16.9% MBF and 24.0% FMF at discharge. Gestational age <37 weeks, caesarean section, multiple births, small for gestational age, weeks at hospital, ≥6 h before skin-to-skin contact, and few weeks at hospital were associated with failure to EBF at discharge. Median (min-max) ΔWAZ in EBF, MBF and FMF infants was -0.44 (-4.78 to 4.88), -0.43 (-3.47 to 4.42) and -0.39 (-3.54 to 4.03), respectively. ΔWAZ was higher in EBF compared to FMF infants, p-value 0.01, but no significant difference in ΔWAZ between MBF and FMF infants, p-value 0.06.

Conclusion: Danish newborn infants demonstrated satisfactory growth during admission to the neonatal unit, independent of feeding type at discharge. Rates of exclusively breastfeeding need improvement.