Expressing, storing and transporting breast milk - PDF checklist
This material concerns a mother's own milk for a healthy, full-term baby at home. It does not cover fortified milk, donor milk or preparing formula. For a premature or ill baby, or a hospital stay, follow an individual protocol. Childcare providers may have separate rules.
Expressing needs a purpose and comfortable conditions
How often and how you express depend on your family's situation and your baby's feeding. Not every parent needs large reserves or the same device. Read the instructions, check the fit of parts and ask for a demonstration if expressing is difficult or painful. This material does not set a schedule to increase milk supply or a technique to treat blocked milk ducts.
Washing and additional sanitising are different tasks
Parts that touch milk need thorough washing after every use and complete drying. Check which parts can go in a dishwasher or be steam-treated according to the instructions. Agree additional sanitising with your care team, especially where infection risk is higher. Putting used parts in the fridge does not replace washing; we do not present it as a safe everyday routine.
Time only makes sense alongside conditions
A separate page gives clearly labelled CDC reference points. These are not a shared standard for every country. Temperature, cleanliness, health and changes in conditions matter. Individual NHS and HSE publications give different refrigeration periods and rules after thawing or starting a bottle. Choose a current local plan with your care team and agree it with the carer; do not pick the longest times from different tables.
Chilled transport does not restart the clock
CDC allows transport in an insulated bag with frozen ice packs for up to 24 hours while milk stays cold. This is a conditional limit, not a promise about every bag. Provide suitable conditions immediately on arrival. The milk's previous age and post-thawing limits still apply; do not refreeze fully thawed milk. If the time is unknown or cooling has been interrupted, do not judge suitability by smell alone.
Preparation checklist
Prepare for expressing and hygiene
- Wash your hands and prepare a clean space, working equipment and containers intended for breast milk or food.
- Check the pump instructions and fit; discuss pain or skin damage with a midwife or lactation professional.
- Wash parts that touch milk after every use; leave them to air-dry completely.
- Agree additional sanitising and safe storage of dry parts according to the local plan and the instructions.
Label and maintain suitable conditions
- Close the container securely; label it with the date and time of expression and any details the carer requires.
- Chill milk intended for later; monitor the appliance temperature and do not store milk in the fridge door.
- Choose portions for your needs and, when freezing, leave space for expansion according to the container's instructions.
- Cool fresh milk before combining portions; use the oldest portion's date and do not extend its storage time.
Plan transport and feeding
- Use an insulated bag with frozen ice packs; agree the journey time, how to keep milk cold and transfer to a fridge on arrival.
- Thaw in the fridge or warm water; do not use a microwave or heat directly on the hob.
- Note when the relevant time starts: complete thawing, warming or the end of a feed; the earlier limit applies.
- Do not refreeze fully thawed milk; do not give it to your baby if the time or conditions are uncertain.
Questions to discuss with a professional
- Which current guidance and exact conditions apply to our situation?
- How should we wash and additionally sanitise our equipment and organise cooling?
- Which time limits and labels should we agree with the person or provider receiving the milk?
Frequently asked questions
Why is the table labelled CDC?
It clearly identifies one set of recommendations for healthy, full-term babies at home. Other institutions give different limits. For example, the cited NHS page advises using thawed milk straight away and leftovers within 1 hour, while CDC gives different conditions. Do not combine these tables into one set of instructions.
Should we restart the clock after chilling or transport?
No. Keep the oldest portion's date and earlier restrictions. Where several limits apply, use the earlier deadline. Do not refreeze fully thawed milk.
Does the fridge replace washing pump parts?
No. Washing parts that touch milk after every use and complete drying remain essential. Refrigeration does not remove dirt or completely stop microbial growth.
Breast milk: CDC reference points
Source: CDC (USA), checked 07.11.2026. For healthy, full-term babies at home, with hygienic expression and conditions maintained. Does not replace a local or individual plan. The maximum times given are not storage targets.
- Freshly expressed, before feeding has started
- Up to 4 hours at 25°C or lower. Chill as soon as possible if keeping for later.
- Fresh milk in the fridge
- Up to 4 days at 4°C or lower; store inside the fridge, not in the door.
- Milk in the freezer
- At -18°C or lower: best used within 6 months; up to 12 months is acceptable according to CDC.
- Previously frozen, thawed in the fridge
- In the fridge at 4°C or lower: up to 24 hours from COMPLETE thawing. Do not count from removal from the freezer, and do not refreeze.
- After refrigeration: warmed or at room temperature
- Use within 2 hours of warming or reaching room temperature. Keep the earlier limit.
- Milk left in a bottle after a feed
- According to CDC, use within 2 hours of the END of the feed, taking earlier limits into account.
How to use this checklist
Tick the points you have discussed or prepared and add your own arrangements. Ticking a box does not confirm safety, health status or completion of a medical procedure. Revisit the checklist as your family's needs change.