Ideally, your milk should be stored in single-serving portions (approximately 2 oz. each) that can be combined if necessary to minimize waste. When it comes time to thaw your frozen milk, simply place the unopened container in the refrigerator or in a pan of warm water. Thawing in a fridge will take more time, so this should be done well before your child begins to show signs of hunger. Placing the unopened container upright in a pan of warm water will speed up the thawing process. Even if your child is very hungry, do not thaw your milk in a microwave oven; doing so destroys live cells and heats the milk unevenly, increasing the risk of burning your baby.
Your milk can be served at room temperature. No heating is necessary. If your baby prefers milk warm, you can place the unopened container upright in a second pan of warm water for several minutes or run the bottom of the container under warm water from the faucet (just be sure that no water enters the container itself).
Keep in mind that storage guidelines are different for thawed milk compared to fresh:
- Milk that has been thawed in the fridge should be used within 24 hours.
- Milk that has been thawed in a pan of warm water should be used right away or stored in the fridge for up to 4 hours.
- Previously frozen milk leftover in the feeding container should be discarded.
- Fresh milk leftover in the feeding container should be stored in the fridge and used within 1 hour to complete the baby’s feeding.
For guidance on introducing a bottle and avoiding nipple confusion, see here.