Babies like warm milk and when they are at the breast, milk is naturally warmed to body temperature. Yet, understandably, many mothers ask why they can't give their baby cold expressed milk -- they don't want their babies to get used to warm milk if they happen to be out and aren't able to warm a bottle.
The truth is, many babies are absolutely fine with cold milk, while others won't accept it. Is it harmful? It's unclear -- research hasn't been done that shows whether cold milk causes gas or colic. So, the temperature of the breastmilk you give to your baby largely depends on you and your baby's situation and preferences.
How To Thaw Frozen Breast Milk
- Set the container in a pan of cool water for approximately 5 minutes. Do not allow the water to cover the container; otherwise, beads of water can taint the milk as it is being poured.--OR--
- Use a special dry warming device.--OR--
- Put it in the refrigerator overnight. It can then be stored there and used within the next 24 to 48 hours.
Once frozen milk is thawed, it can be kept refrigerated, but cannot be refrozen.
How to Warm Expressed Milk
- To achieve feeding temperature, place the container of milk in a pan of warm water. Bottle warmers are also a nice option.
- Test the comfort of the milk frequently on the wrist.
- Warming the bottle nipple is also recommended when first introducing the bottle to the baby.
- Never microwave breast milk for two reasons: One, it starts to lose essential nutrients when it is warmed above body temperature. Two, just like microwaved food, it can have hot spots and mouths of babies have been burned from hot milk when the container felt comfortably warm.
Upgrading and Downgrading Breastmilk
It is also important that expressed and stored milk is treated well. An easy rule to remember is that milk can be "downgraded," but never "upgraded." In simpler terms, if milk is in the freezer, it can be downgraded and placed in the refrigerator, and if it's in the refrigerator, it can come out to the counter. But milk cannot be upgraded from the refrigerator to the freezer, or from the counter (after it has been out for a while) to the refrigerator.
Also, once milk has been defrosted and warmed, it cannot be cooled and warmed again. (Think about how defrosted meat or chicken is treated. If it's taken out and thawed in the fridge, it can't be placed back in the freezer. It has to be cooked.)
Any milk expressed within a 24-hour period can be pumped into the same container if the earlier expressed milk was stored between 32 F to 60 F. It is important to then adhere to the storage recommendations based upon the time and date of the first milk expressed. A mother can pump directly into milk that has been stored at room temperature as long as she does so within 6 hours. This milk must then be used.
Important to note:
It is not recommended to give a baby breast milk that was left from a prior feeding or that was previously warmed. Not enough research has been done to prove the safety of this practice.
If you are storing breast milk at work or someone else is using it at daycare, it is fine to be kept in a common refrigerator and no particular handling precautions are required (other than the standard recommendations listed above.)