IS IT OK TO MIX HUMAN MILK AND FORMULA?
Supplementation means giving your baby liquid nourishment in addition to breastfeeding. Supplementation of a breastfed baby may be necessary if the mother’s supply is low or if the baby is separated from the mother. If the reason is low milk supply, your local La Leche League Leader can offer suggestions to help increase the amount of milk you produce. This post may also help: Building a Milk Supply
If supplementing your baby with additional milk is necessary, there are many options for what to use to supplement, and how to do it. This is the World Health Organization hierarchy of what to feed infants: breastfeeding first; expressed mother’s own milk next; milk from a healthy other mother next, then pasteurized donor milk, then manufactured formulas that are regulated by Codex Alimentarius. You and your health provider can work out a plan that better fits your baby’s needs. Your local La Leche League Leader can discuss your particular circumstances.
If your baby needs supplementing with formula milk, a common question is whether it is appropriate to mix breastmilk and formula in the same container, and the answer is that it may be preferable to do separate feedings. One reason is that mixing breastmilk and formula can result in breastmilk being wasted, if the baby does not finish the milk (since the formula needs to be discarded). Giving your pumped milk to your baby first, and on its own, ensures that all of your “liquid gold” will be used and less will be wasted. It’s also important for you or any caregiver providing a bottle to your baby to practice paced bottle feeding, so the milk is offered in a manner similar to breastfeeding and your baby doesn’t develop a preference for the faster flow of a bottle.
Additionally, as part of a review of published research conducted on preterm babies, Schanler (2007) suggests that mixing formula milk and breastmilk can affect protein intake, and retentions of calcium, phosphorus, and zinc: the researcher suggests alternating formula and breastmilk feeds separately, instead of mixing both in the same container.
You can find more information about giving your baby supplements here https://www.llli.org/breastfeeding-info/supplementing/
Schanler, R. J. (2007) Human milk supplementation for preterm infants, Acta Paediatrica Volume 94, Issue s449 (accessed 04.16.2019)