Basics of storing expressed breast milk

Now that we’ve gone through the basics of expressing breast milk, it’s important to also know how to store and thaw the milk so that it is safe for use by your baby immediately, the next day or even after a few weeks.

The Academy of Breastfeeding Medicine recommends using the following guidelines for storing expressed breast milk (EBM) for healthy term babies.

ABM milk storage guidelines

By following these guidelines, you can be sure that all the important nutrients in the breast milk are preserved and bacterial contamination is minimised.

Therefore, if you’re a working mum or away from home and your baby for a long period of time and you’ve expressed during the course of the day, you can either store your expressed breast milk (EBM) in a refrigerator or if you don’t have access to one, you can use an insulated cooler bag with ice packs. This is especially important if you’re likely to take a while before getting home to refrigerate the milk or to feed it to your baby.



Some insulated cooler bags come with their own ice pack(s) that are placed in the freezer then removed as and when required for use without the need to add water to the pack. These tend to be less messy than “home-made” ice packs because when they begin to defrost, they won’t leave pools of water or spill out.


However, if you’re unable to find an insulated cooler bag with ice packs or if they’re too expensive, you can still buy a basic cooler/thermal lunch bag and make your own ice pack using zip-lock bags which you then add water to and freeze.

When you’re ready to leave the house for work in the morning, remove the now frozen ice pack, place it in the cooler bag and it should still be frozen once you’re ready to store your EBM in the bag.


  • Avoid filling storage bottles/ bags to the brim in order to allow space for possible expansion when the milk freezes.
  • Label the bottle/bag with the date you expressed the milk so that you can follow the “first in, first out” rule. This means that with the earliest date should be used first because it has been in the fridge/freezer for the longest.
  • Avoid storing breastmilk in the refrigerator door. Store it in the lower back area of the refrigerator, where the temperature is coolest.
  • Expressed breast milk can be used straight from the fridge or it can be warmed gently by placing the bottle or bag in a bowl of warm water.
  • Thaw/defrost frozen breastmilk in the refrigerator overnight and use the milk within 24 hours of removing it from the freezer.
  • You can also thaw/defrost the milk quickly by placing the bottle or bag in a warm water (max. 37° C).
  • Defrosted milk should be used within a few hours to avoid contamination.
  • DO NOT thaw/defrost frozen breastmilk in a microwave oven or in a pan of boiling water because microwaves do not heat evenly, and exposure to high temperatures can destroy essential nutrients and antibodies in the expressed breast milk.
  • DO NOT return defrosted breast milk to the fridge for a later feed if the baby does not finish it the first time, and this also applies to freshly expressed breast milk. As long as the baby’s mouth has come into contact with the milk, any left overs should not refrigerated. If you are afraid of wastage, store your expressed breast milk in smaller quantities.



Express Yourself

As a new mum, especially a working mum, you may be wondering how you’ll be able to exclusively breastfeed your baby for the first 6 months of life and partially thereafter, if circumstances keep you away from your baby for extended periods.

Fortunately, there is a way of ensuring that breast milk remains the only form of nourishment your baby receives in your absence, and this is by expressing your breast milk.

Expressing breast milk is the act of emptying the breast without your baby suckling. It can be done using the following methods:

  • By Hand
  • Manual Breast Pump
  • Electric Breast Pump

Hand expression is the cheapest and most convenient method because it doesn’t require any special equipment and can be done anywhere so long as your hands and your surroundings are hygienic. All you need is a sterile container to collect the milk in.

Expressing by hand can however be a difficult technique to master because it requires you to massage and compress the milk ducts behind the nipple rather than the nipple itself.

Some common mistakes mums make when hand expressing are rubbing the skin on the breast and/or squeezing the nipple but this only hinders the flow of milk.

The most effective technique is to:


  • Massage the breast with the palm of your hand to stimulate let down
  • Place your thumb and forefinger on either side of your nipple at the edge of the areola
  • Using your thumb and finger, gently press your breast tissue back towards your chest wall and compress forwards. By doing this way you’re moving back along the milk ducts and pushing the milk forward.
  • Continue pressing back and compressing in a rhythmic massaging movement until the milk begins to flow but take care not to move your fingers onto the nipple otherwise you might block the flow of the milk.
  • Keep changing the position of your fingers around the breast to ensure you empty all the ducts.
  • Once the milk flow slows down, change to the other breast. Keep alternating between both breasts until the compression no longer trigger a substantial let-down or flow.

Here is a link to an informative video on how to hand express:

In the beginning it can be time consuming and tiring but once you master the technique, hand expression is the best way of making sure you collect the most milk.

Breast pumps are designed to mimic the suckling action of your baby thus stimulating the let-down reflex automatically.

Majority of pumps have a suction cup at the top (which is placed on the breast) and attached to a container for collecting the expressed milk.

manual and electic pumps


Manual breast pumps have a handle that needs to be repeatedly squeezed in order to extract the breast milk whereas electric breast pumps have motors that are mains and/or battery operated and automatically run the pump.

The best pump for you will depend on:

  •   How often you intend to express you breast milk
  •   How much time you’ll have for expressing

If you only intend to express occasionally, for instance once or twice a day, a manual pump and hand expression are most suitable.

If however, you need to express 3-4 times a day and with a limited time period to do so, an electric breast pump is most suitable.

If you’re expressing on more occasions than you are breastfeeding, for instance, you work far from home or you have multiples or a baby who cannot latch on well, a double electric pump is advisable.

pumping at work
Woman using a double pump to express milk at her work desk. Photo courtesy


Key Tips:

  • Expressing should not be painful
  • Take time to learn how to express your breast milk properly. As with breastfeeding, expressing is a learned skill and be prepared to seek professional help if necessary.
  • Expressing can be used to stimulate and increase breast milk supply by increasing the frequency with which the breast is emptied.
  • Aim to express or breastfeed every 3-4 hours in order to maintain your milk supply. The longer you leave it before emptying your breasts, the less your body will produce.
  • The best time to express your milk is between midnight and 4am when the level of prolactin (the milk producing hormone) is at its highest.
  • Use the hand expression technique at the beginning of a breast pumping session to stimulate the let-down reflex and at the end to ensure you completely empty the breast.