Early Enteral Feeding in Preterm Infants: A Narrative Review of the Nutritional, Metabolic, and Developmental Benefits

Abstract

Enteral feeding is the preferred method of nutrient provision for preterm infants. Though parenteral nutrition remains an alternative to provide critical nutrition after preterm delivery, the literature suggests that enteral feeding still confers significant nutritional and non-nutritional benefits. Therefore, the purpose of this narrative review is to summarize health and clinical benefits of early enteral feeding within the first month of life in preterm infants. Likewise, this review also proposes methods to improve enteral delivery in clinical care, including a proposal for decision-making of initiation and advancement of enteral feeding. An extensive literature review assessed enteral studies in preterm infants with subsequent outcomes. The findings support the early initiation and advancement of enteral feeding impact preterm infant health by enhancing micronutrient delivery, promoting intestinal development and maturation, stimulating microbiome development, reducing inflammation, and enhancing brain growth and neurodevelopment. Clinicians must consider these short- and long-term implications when caring for preterm infants.

Keywords: development; enteral; feeding; growth; nutrition; preterm.

Figure 1

Cross Section Stain of Villi in the Ileum of Preterm (A) vs. Term (B) Piglets. Figure reproduced from Frontiers in Immunology, Vol. 9, Page 5 as available via Open Access and under terms of the Creative Commons Attribution License. Original article published as “Preterm Life in Sterile Conditions: A Study on Preterm, Germ-Free Piglets” by Splichalova et al., 2018 [51].

Figure 2

A Macroscopic Appearance and Stained Cross Section of Distal Small Intestine in Preterm Piglets Receiving Enteral Feeding vs. Total Parenteral Nutrition (TPN). Figure modified and reproduced with copyright permission from American Journal of Physiology-Gastrointestinal and Liver Physiology, Vol. 302, page 221, Copyright © 2012 by The American Physiological Society. Original article published as “Enteral Bile Acid Treatment Improves Parenteral Nutrition-Related Liver Disease and Intestinal Mucosal Atrophy in Neonatal Pigs” by Jain et al. [52].

Figure 3

Proposed decision making for initiating and advancing enteral feeding in preterm infants.

Figure 4

Comparison of adequate (Example A) vs. early growth failure (Example B) for linear growth in an extremely low birth weight infant from 25–40 weeks gestation with adequate weight gain. Examples A and B 2013 Fenton growth charts constructed and reprinted from the PediTools.org website [89,91,92] as available via open access and under terms of the Creative Commons Attribution License.

Figure 5

Comparison of body mass index trend from 25–40 weeks gestation in an extremely low birth weight infant with adequate (Example A) vs. early growth failure (Example B) for linear growth when weight gain is adequate. Examples A and B modified and reproduced with permission from first author Irene Olsen, published in Pediatrics, Vol. 135, page 575, Copyright © 2015 by the American Academy of Pediatrics. Original article published as “BMI Curves for Preterm Infants” by Olsen et al. [90].