If you need to return to work or need to be away from work but want to continue breastfeeding your baby, you can express your milk to store breast milk. However, storage precautions must be observed to avoid any risk of contamination.

It is quite possible to store breast milk at room temperature, in the refrigerator or in the freezer depending on how long you want to keep it. Whatever storage method you choose, take care both to wash your hands thoroughly and to wash your breast pump and the container in which you will store your breast milk.

For short term storage

You can always keep your breast milk at room temperature, provided of course that you offer it to your child within hours:

• 4 to 6 hours, maximum 8 hours at room temperature (between 19 and 22 ° C)
• 24 hours at 15 degrees.

However, ANSES specifies that any bottle started but not finished within one hour after the start of its consumption must be discarded. Indeed, once the bottle has been brought to the mouth, there is a transfer of bacteria that contaminate the milk and the fact of putting the bottle in the refrigerator does not prevent the development of bacteria.

For medium and long term storage

If you need to keep your breast milk longer, it is essential to limit bacterial proliferation, by opting either for the refrigerator or for the freezer. In this case, you can keep your milk:

• 5 to 8 days in the refrigerator (between 0 and 4 ° C)
• 2 weeks in the freezer of a refrigerator: this is the compartment intended for storing frozen foods, at the top of a refrigerator
• 3 to 4 months in a fridge-freezer combination
• More than 6 months in a freezer separate from the refrigerator (-18 ° C)

However, due to the risks of bacteriological development, the times mentioned cannot be cumulated. Thus, it is strongly recommended not to store your milk at room temperature for 6 hours and then freeze it for 6 months. In addition, these maximum storage periods are valid for domestic use. Hospitals have much more stringent requirements of their own to limit any risk of contamination.

The fridge

If you want to store your breast milk for a relatively short time – less than 8 days – you can store it in the coldest part of your refrigerator. This part is not located in the same place from one model to another but it is generally indicated in the device using a pictogram (often a snowflake or “OK”). If not, feel free to use a thermometer to compare the temperature of different places in your refrigerator, top and bottom. Breast milk should be stored between 0 to 4 ° C.

On the other hand, avoid placing your breast milk in the door of your refrigerator because this is the part that undergoes the most temperature variations.

The freezer

For mothers who have to take time off or return to work, freezing is the ideal solution for stocking up on breast milk. Take into account the type of appliance you have to assess the maximum shelf life: freezer (compartment located at the top of a refrigerator, intended to store frozen products), combined fridge-freezer or independent freezer. Note, however, that milk can be stored in the best case (freezer separate from the refrigerator), 6 months only. So remember to properly label your containers to make a rotation and give your child the oldest milk reserves. The trick is therefore to reserve a special container for your breast milk and to place the milk that you have just drawn behind the one that you have previously frozen. As a priority, you will thaw the containers in front of you.

Also, be sure to only fill the containers two-thirds to avoid the explosion of the milk when it crystallizes and remember to freeze your milk in small quantities to avoid waste. In this sense, ice cube trays can be an excellent storage container.

Regarding milk that you have stored at room temperature, you can place it in the refrigerator for 4 days if it has not been left for more than two hours at a maximum temperature of 22 ° C. You can also keep it in the freezer if you wish, under this same condition.

In addition, whatever the mode of conservation chosen, it is recommended to cool the breast milk as soon as it is collected, under a trickle of cold water before storing it.

If the milk has been frozen, it is quite possible to let it thaw in the coldest part of your refrigerator for two to three days. But you can also reheat it directly, just like if it had been stored in the refrigerator.

For this, it is advisable to heat the milk gently in a bain-marie rather than in the microwave: you will avoid heating it too quickly and altering its nutritional qualities.

Of course, always check the temperature of the milk by pouring a drop into the crook of your wrist before offering the bottle to your baby. Also remember to shake the bottle well to mix the different phases of the milk and thus provide your child with all of its nutritional qualities.

As a reminder, thawed milk, even partially, cannot under any circumstances be re-frozen, otherwise bacteria may proliferate.

1. Always be sure to wash all equipment that comes into contact with your breast milk: breast pump utensils, storage containers, bottles, etc. And wash your hands well before handling the milk.
2. Use glass or plastic containers or freezer bags specifically dedicated to storing breast milk. For these small sachets, do not be tempted to reuse them: throw them away as soon as they have been used once!
3. Freeze your milk by volume of 60 to 120 ml: defrosting will be easier and you avoid wastage if your baby does not drink all of his bottle. Milk cannot be stored if it has already been reheated.
4. Once you have expressed your milk, make it a habit to always note today’s date on the storage container and add your baby’s first name if it is being kept with other children to avoid confusion.
5. Always use the oldest milk (according to the date you have entered) to ensure a good rate of conservation. To do this, establish a logic in your storage, for example by placing each new container behind the previous one.

Finally, if your baby refuses to drink the milk that you have stored in the refrigerator or freezer even though you have followed the storage instructions, don’t worry because it is just the taste and smell of your milk. were changed when it was cooled. In this, it is enough, just after having drawn your milk to heat it for a few minutes in a saucepan at 50-60 ° C (the milk begins to smoke slightly and to simmer on the edges). Then cool the milk quickly under running cold water, before freezing it or putting it in the refrigerator.