This study is a randomized controlled trial seeking to determine whether supplementing infants at risk for excessive neonatal weight loss with a small volume of human donor milk prophylactically in the first 1-3 days of life, before maternal mature milk production (before mom's milk "comes in") will decrease the incidence of formula use at 1 week and 1, 2, and 3 months of life and increase the rate of exclusive breastfeeding in this high-risk population.

We hypothesize that supplementation of term infants who have lost greater than or equal to 5% birth weight by 36 hours of age with a small volume of donor breast milk following feeds, until mature milk production, will result in decreased supplemental formula use at 1 week and increased exclusive as well as any breastfeeding at 1 week and 1, 2, and 3 months. This study's specific aims are to compare the effectiveness of encouraging in-hospital exclusive breastfeeding with offering early small-volume donor milk supplementation in a population of infants at risk for excessive neonatal weight loss with goals of 1) decreasing the incidence of formula supplementation at 1 week of life and 2) improving breastfeeding duration.

Inclusion Criteria:

• Gestational age greater than or equal to 37 weeks
• Weight loss greater than or equal to 5% (rounded to nearest whole percent) of birth weight in the first 36 hours after birth
• Chronologic age of 24-48 hours old at the time of study enrollment

Exclusion Criteria:

• twins and higher level multiples
• infant has congenital or chromosomal anomalies that may affect feeding, diagnosed prior to study enrollment
• mother incarcerated
• mother's age <18 years
• mother reports mature milk production prior to study enrollment
• mother does not speak English
• infants offered > 1 supplemental feeding of formula or donor milk
• weight loss greater than 10%