Epigenetics Embedding of Oral Feeding Skill Development in Preterm Infants: A Study Protocol.

Background: Preterm infants face challenges to feed orally, which may lead to failure to thrive. Oral feeding skill development requires intact neurobehaviors. Early life stress results in DNA methylation of NR3C1 and HSD11B2, which may disrupt neurobehaviors. Yet, the extent to which early life stress impairs oral feeding skill development and the biomechanism whereby this occurs remains unknown. Our team is conducting an NIH funded study (K23NR019847, 2022-2024) to address this knowledge gap.

Purpose: To describe an ongoing study protocol to determine the extent to which early life stress, reflected by DNA methylation of NR3C1 and HSD11B2 promoter regions, compromises oral feeding skill development.

Methods: This protocol employs a longitudinal prospective cohort study. Preterm infants born between 26 and 34 weeks gestational age have been enrolled. We evaluate early life stress, DNA methylation, cortisol reactivity, neurobehaviors, and oral feeding skill development during neonatal intensive care unit hospitalization and at 2-week post-discharge.

Results: To date, we have enrolled 70 infants. We have completed the data collection. Currently, we are in the data analysis phase of the study, and expect to disseminate the findings in 2025.

Implications for practice and research: The findings from this study will serve as a foundation for future clinical and scientific inquiries that support oral feeding and nutrition, reduce post-discharge feeding difficulties and lifelong risk of maladaptive feeding behaviors and poor health outcomes. Findings from this study will also provide further support for the implementation of interventions to minimize stress in the vulnerable preterm infant population.