Breast Milk Substitute Intolerance clinical trials at UCSF

Late preterm infants, who are born at 34, 35 or 36 weeks gestation, often have difficulty feeding, establishing growth, and fighting off infection. Breastfeeding provides improved nutrition to help fight infection, in part because breast milk encourages the growth of healthy bacteria (microbiota) in the infant's intestine. However, when mothers give birth preterm, their breasts are usually not quite ready to make milk; it can take several days to have enough breast milk to match a baby's nutritional needs. If there is not yet enough breast milk, formula is often used. However, formula can interfere with the growth of healthy intestinal bacteria. An alternate nutritional option is donor milk from a certified milk bank, which is available in all neonatal intensive care units (NICUs) in San Francisco. However, no scientific studies have yet studied donor milk for late preterm infants, so currently all San Francisco NICUs (as well as the large majority of NICUs nationwide) reserve donor milk for infants born at <34 weeks. This study's investigators therefore propose the "Milk, Growth and Microbiota (MGM) Study," a randomized controlled trial to compare banked donor milk to formula for breastfeeding late preterm infants born in San Francisco. Once enrolled in MGM, infants will be randomly assigned to receive either formula or banked donor milk if they need additional nutrition until their mothers are making enough milk. After enrolling the babies, investigators will weigh them daily to assess their growth. The investigators will also collect infant bowel movements at baseline, 1 week and 1 month to determine whether donor milk vs. formula impacts the type of bacteria in the baby's intestine. If the study's results show that donor milk optimizes growth while helping establish healthy bacteria in the baby's intestine, donor milk might be postnatal strategy to bolster neonatal nutrition for late preterm infants.