Predictors of Direct Breastfeeding in Preterm Infants

Background: Rates of mother’s milk provision in the neonatal intensive care unit (NICU) vary widely, despite being accepted as the gold standard for nutrition in preterm and critically ill infants. Direct breastfeeding (DBF) supports long-term provision of mother’s milk and increases the chances that an infant will continue to receive mother’s milk at NICU discharge. Similarly, DBF as the first oral exposure may result in important feeding imprinting on the developing brain that promotes ongoing breastfeeding competence and maintenance of lactation. Feeding characteristics and modifiable factors that predict DBF are currently unknown. The objective of this study is to identify factors that predict DBF at oral feeding initiation and at NICU discharge.

Methods: We performed a retrospective chart review to evaluate factors associated with DBF in preterm infants born at ≤ 32 weeks admitted to the University of Cincinnati Medical Center NICU from January 2017 through December 2019. Infants receiving mother’s milk at 32 weeks corrected gestational age and at discharge to home with no co-existing conditions that preclude oral feeding were included. Our primary outcomes were rates of DBF at 1) oral feeding initiation and 2) hospital discharge, which we defined as any direct breastfeed that occurred within 1 week of starting oral feeds and 1 week prior to discharge, respectively. Factors examined in relation to both outcomes include gestational age at first oral feeding, degree of respiratory support, and timing and frequency of lactation consultation; additionally examined in relation to DBF at discharge were DBF as the first oral exposure, gestational age at first DBF and days between first DBF and first bottle feed.

Results: The mean gestational age (in weeks) of the cohort was 29.7 (SD 1.8) and mean birthweight (in grams) was 1310 (SD 428). Median 1- and 5- minute Apgars were 7 (range 0-9) and 8 (range 1-9), respectively, with 75% of infants being born via cesarean section. Of 259 infants receiving mother’s milk at 32 weeks corrected gestational age, 165 (64%) were directly breastfed at the time of oral feeding initiation. Of 191 infants still receiving mother’s milk at hospital discharge, 85 (44%) directly breastfed at least once in the week prior to discharge home. Characteristics of infants and mothers did not significantly differ between those who were DBF at oral feeding initiation and discharge compared to those who were not.

Conclusion: Despite being associated with increased rates of mother’s milk provision, rates of DBF in the NICU are low. Evaluation of predictor variables will help identify factors associated with breastfeeding success. Factors such as feeding imprinting, lactation support and degree of illness may all contribute to the success of DBF throughout the NICU stay.