Breastfeeding
Going back to work and breastfeeding
Which breastfeeding breaks you are entitled to under § 170 of the Slovak Labour Code, how to use them for expressing, how to prepare and how to store milk at work.
3 min read
Expressing and storing breast milk
Expressed milk gives you freedom: someone else can do a feed, you can go back to work or just go out for a few hours. To keep it safe, you need to know a few simple rules about cleanliness and timings.
By hand or with a pump
| Hand expressing | Manual pump | Electric pump | |
|---|---|---|---|
| For | the first days, colostrum, relief when your breasts are full | occasional expressing | regular expressing, going back to work |
| Pros | needs nothing, works anywhere3 | cheaper, quiet, light4 | faster, less effort4 |
| Cons | takes practice | slower, tires your hand | cost, noise, more parts to wash |
Hand expressing in brief
The NHS describes the steps: wash your hands, have a clean container ready, gently massage the breast from the armpit towards the nipple, place your fingers in a C shape a little way back from the areola, and rhythmically press and release. Drops appear after a while, and then milk may start to flow.3 Ask a midwife or lactation consultant to show you.
A pump
The NHS advises having the pump and all its parts clean and sterile before use, and with an electric pump starting on the lowest setting and turning it up once milk begins to flow.4 Make sure the breast shield (flange) is the right size; it should not hurt.
Cleanliness
- Wash your hands with soap and warm water before expressing.3
- Wash and sterilise the pump parts and containers following the manufacturer’s instructions.4
- Store the milk in clean food-grade containers or breast milk bags with a tight seal.1
How long milk keeps
| Where | Freshly expressed milk | Thawed milk |
|---|---|---|
| Room temperature (up to 25 °C) | up to 4 hours1 | once at room temperature or warmed, within 2 hours1 |
| Fridge (4 °C or colder) | up to 4 days1 | within 24 hours of fully thawing1 |
| Freezer (−18 °C or colder) | best within 6 months, acceptable up to 121 | do not refreeze1 |
The CDC gives temperatures in degrees Fahrenheit (77 °F, 40 °F, 0 °F); we have converted and rounded them. The CDC recommends checking the fridge and freezer temperature with a thermometer.2
Practical rules
- Do not store milk in the door of the fridge or freezer; the temperature is more stable further in.1
- If you won’t use it within 4 days, freeze it as soon as possible.1
- Label it with the date you expressed it; the age of frozen milk counts from when it was first frozen.2
- Freeze in smaller portions, so you don’t have to pour leftovers away.2
- When travelling, milk keeps for up to 24 hours in a cool bag with ice packs; at your destination, use it straight away, put it in the fridge or freeze it.1
Thawing and warming
The CDC gives these ways to thaw milk: overnight in the fridge, in warm or lukewarm water, or under lukewarm running water.1 Use milk thawed in the fridge within 24 hours. Once milk has been warmed or brought to room temperature, use it within 2 hours. Throw away what is left after a feed within 2 hours of the end of the feed.1,2
The CDC recommends not warming milk in a microwave, because it heats unevenly.1
Power cuts
The CDC says that a full freezer kept closed keeps food safe for about 48 hours, a half-full one for about 24 hours, and a closed fridge for about 4 hours.2 Keep the doors shut during a power cut.
Next
Frequently asked questions
Can I add freshly expressed milk to milk that has already been chilled?
The sources we rely on do not go into this in detail in the recommendations cited, so we will not guess. The safe course is to store each expressing session in a separate container and label it with the date.
Can I use leftover milk from a bottle at the next feed?
The CDC says that milk your baby has not finished should be used within 2 hours of the end of the feed; after that it should be thrown away.
Where this comes from
The numbers in the text refer to these sources. The links go to the publishers’ own pages; we simply cite them.
- CDC (USA):Breast Milk Storage and PreparationStorage times, thawing, warming.
- CDC (USA):Breast Milk Storage – Questions and AnswersLeftovers within 2 hours, fridge and freezer temperatures, power cuts.
- NHS (United Kingdom):Expressing and storing breast milkHand expressing, cleanliness and sterilising.
- NHS Start for Life:Expressing breast milk with a pump
We last checked these sources on 13 October 2026.
Further along the path
Breastfeeding
Breastfeeding – a guide to the first weeks
The first feed, how often to breastfeed a newborn, signs of a good latch, how many wet nappies to expect, when your milk comes in and when to get help. Based on the WHO and the NHS.
In-depth guide 5 min read
Clothes
Nursing tops and vests
Short sleeves, long sleeves, a vest under a hoodie or a shirt for work. How to choose a nursing top that opens with one hand and stands up to frequent washing.
2 min read