Early human milk feeding: Relationship to intestinal barrier maturation and postnatal growth.

Objectives: Early exposure to mother's own milk (MOM) promotes intestinal barrier maturation in preterm infants. We hypothesized (1) donor human milk (DHM) supplementation reduces intestinal permeability (IP) similar to exclusive MOM and (2) early HM exposure and low IP at 7-10 days postnatal age (PNA) are associated with improved growth outcomes.

Methods: IP was measured by the standard sugar absorption test (SAT) in infants <33 weeks gestation between 7-10 days PNA. Nutritional and anthropometric data were recorded. Postnatal growth failure (PNGF) was defined as a decrease in weight z-score >1 from birth to discharge to home.

Results: Of 158 preterm infants, the mean (SD) gestational age was 29.9(2.3) weeks and birthweight 1388(424) g. Diet prior to SAT was exclusive MOM [N = 55(35%)], DHM ± MOM [N = 52(33%)], or preterm formula±MOM [N = 51(32%)]. The mean Lactulose(La)/Rhamnose(Rh) ratio was lower in the exclusive MOM [0.06(0.07)] and DBM ± MOM [0.05(0.07)] groups compared to the preterm formula±MOM group [0.11(0.11)], p < 0.01). Cumulative intake >150 ml/kg MOM ± DHM, but not preterm formula within 7-10 days PNA was associated with early intestinal barrier maturation. Low IP was not associated with lower risk of PNGF at discharge.

Conclusions: Low IP is associated with cumulative intake of MOM alone or supplemented with DHM > 150 ml/kg within 7-10 days PNA.

Clinical trial registration: Clinicaltrials.gov NCT01756040 ; web link to study on registry: https://clinicaltrials.gov/study/NCT01756040 .

Impact: Key message Early intestinal barrier maturation is associated with cumulative intake of exclusive MOM alone or supplemented with DHM > 150 ml/kg within 7-10 days after birth, but is not associated with lower risk of PNGF at time of discharge. What it adds to existing literature? This observational study is the first study to demonstrate that supplemental DHM promotes intestinal barrier maturation similar to MOM alone. What is the impact? The findings underscore the importance of early introduction of human milk feeds as MOM or MOM supplemented with DHM in sufficient volume to promote early intestinal barrier maturation.