Expressing Breast Milk: Safety & Hygiene


  • Find a clean place to express in. Avoid using a toilet, bathroom, kitchen or other places where food is prepared.
  • Wash hands thoroughly before starting.


Equipment cleanliness:

  • Use soap and water to clean your pump.
  • Dry it with fresh paper towels.
  • Remember to sterilise it every day.



  • Continue pumping as long as your milk flows well. Switch breasts once the flow slows down. Repeat (each breast should be pumped twice).
  • Sit in a comfortable position while supporting your breast, i.e. place the palm of your hand against your ribs and directly under your breast.
  • Be gentle when pumping. Use just enough pressure to maintain a seal rather than pushing the breast pump against your breast.



  • Store the expressed milk in clean containers meant for storing breast milk.
  • Disposable milk storage bags should only be used once.
  • Milk bottles can be reused. Wash with soap and water then sterilise before reusing.
    Caution: Do not overfill containers if you plan to freeze the milk. Liquids expand when frozen and overfilled containers can leak, thus leading to possible contamination of the milk.
  • Always label the containers (date/time expressed and medications taken within 24 hours) before storing them in the refrigerator/freezer. If you are not at home, store it in a cooler with ice packs.
  • Always use the oldest stored milk first.


How to store:

  • Milk may be stored for 24 hours in an insulated cooler bag with ice packs.
  • Milk may be refrigerated at 4°C for up to five days. It is best to store expressed milk at the back of the refrigerator, as far from the door as possible.
    Caution: Milk kept at room temperature (25°C) should be used within six hours. It is not safe to leave milk out for long periods at higher temperatures.


  • Any frozen milk should be used:
    • Within two weeks if kept in the freezer compartment of a single-door refrigerator


    • Within three months if kept in the dedicated freezer compartment of a refrigerator, e.g. two (or more) door fridge


    • Between 6 – 12 months, if kept in a deep freezer that is not frequently opened.


How to thaw frozen breast milk:

  • Defrost it in the fridge overnight.
  • Place the bottle of milk in a bowl of warm water.



Do not thaw or heat up breast milk with a stove or microwave. This will destroy the nutrients! Microwaving can also cause uneven temperature (hot spots) in the milk that could injure baby.

Use after thawing and dispose of any leftovers (do not re-freeze or keep in the fridge again).

Reminder: Always test to ensure that the milk is EVENLY warm and at a suitable temperature by squirting a few drops on your inner wrist before feeding your baby.

An educational collaboration with Nutrition Society of Malaysia.

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