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Pumping, Storing and Thawing Breast Milk


  • Wash hands before pumping or expressing milk.
  • Pump or express several times throughout the day.


Breast milk Storage Guidelines

Room Temperature
Cooler with 3 frozen ice packs
Self-contained refrigerator freezer unit
Deep freezer
Freshly expressed breast milk
Max 4 hours at 66-72°F (19-22°C)
24 hours at 59°F (15°C)
3-5 days at 32-39°F (0°C)
3-6 months
6-12 months at 0°F (-19°C)
Thawed breast milk (previously frozen)
Do not store
Do not store
24 hours
Never refreeze thawed milk
Never refreeze thawed milk

Use containers washed in hot, soapy water, then rinsed well. You can also use plastic bags made for food or breast milk. The guidelines for storing breast milk are below (for full-term, healthy babies). Talk to your health care provider if your baby is premature or sick, as different guidelines need to be used.

  • Cool the fresh breast milk in the refrigerator.
  • Add the cooled milk to a container of already frozen milk.
  • Freeze in small amounts (2 – 4 ounces) to prevent waste.
  • The milk will expand as it freezes. Leave some room in the container for this. If using screw-top containers, do not tighten caps until milk is completely frozen.
  • Label each container with date.

Thawing and using Breast milk

  • Thaw breastmilk by placing container in the refrigerator for 8-12 hours, or put container in warm, running water.
  • Breastmilk can be fed cold, cool or warm – it doesn’t have to be body temperature!
  • Swirl to mix in fats that have separated (do not shake! Shaking can destroy proteins in the breast milk). Breast milk may look, smell and taste different when thawed. This is normal.
  • Discard milk remaining after feed (Once baby’s mouth has touched a cup or bottle, anything in the bottle is contaminated with bacteria and can possibly make baby sick if kept for a later feeding. Milk is a terrific place for bacteria to grow).