Pregnancy information

Expressing breast milk

Expressing milk means squeezing milk out of your breast so you can store it and feed it to your baby later.

You might want to express milk if :

  • you have to be away from your baby, for example, because your baby is in special care or because you're going back to work
  • your breasts feel uncomfortable full (engorged)
  • your baby isn't able to suck well but you still want to give them breast milk
  • your partner is going to help with feeding your baby
  • you want to boost your milk supply

How do I do express milk?

You can express milk by hand or with a breast pump. How often you express milk, and how much you express, will depend on why you are doing it.

Sometimes it takes a little while for milk to start flowing.  Try to choose a time when you feel relaxed.  Having your baby (or a photo of them) nearby may help your milk flow.

You may find it easier to express in the morning, when your breasts can sometimes feel fuller.

Expressing breastmilk by hand

You may find it easier to express milk by hand than to use a pump, especially in the first few days. It also means you won't have to buy or borrow a pump, or rely on an electricity supply.

Hand expressing allows you to encourage milk to flow from a particular part of the breast.  This may be useful, for example, if one of the milk ducts in your breast becomes blocked.

Hold a sterilised feeding bottle or container below your breast to catch the milk as it flows.

The following suggestions may help:

  • Before you start, wash your hands thoroughly with soap and warm water.
  • Have something clean ready to collect the milk in.
  • Some mothers find gently massaging their breasts before expressing helps their milk to let down.
  • Cup your breast with one hand then, with your other hand, form a "C" shape with your forefinger and thumb.
  • Squeeze gently, keeping your finger and thumb near the darker area around your nipple (areola) but not on it (don't squeeze the nipple itself as you could make it sore). This shouldn't hurt.
  • Release the pressure, then repeat, building up a rhythm. Try not to slide your fingers over the skin.
  • Drops should start to appear, and then your milk usually starts to flow.
  • If no drops appear, try moving your finger and thumb slightly, but still avoid the darker area.
  • When the flow slows down, move your fingers round to a different section of your breast, and repeat.
  • When the flow from one breast has slowed, swap to the other breast. Keep changing breasts until your milk drips very slowly or stops altogether.

Expressing milk with a breast pump

There are two different types of breast pump: manual (hand-operated) and electric.

Different pumps suit different women, so ask for advice or see if you can try one before you buy.

Manual pumps are cheaper but may not be as quick as an electric one.

You may be able to hire an electric pump. Your midwife, health visitor or a local breastfeeding supporter can give you details of pump hire services near you.

The suction strength can be altered on some electric pumps. Build up slowly. Setting the strength to high straightaway may be painful or damage your nipple.

You may also be able to get different funnel sizes to fit your nipples. The pump should never cause bruising or catch your nipple as it is sucked into the funnel.

Always make sure that the pump and container are clean and sterilised before you use them.

Storing breast milk

You can store breast milk in a sterilised container or in special breast milk storage bags:

  • in the fridge for up to five days at 4C or lower (you can buy cheap fridge thermometers online) – if you're not sure of the temperature of your fridge, or it is higher than 4C, use it within 3 days
  • for two weeks in the ice compartment of a fridge
  • for up to six months in a freezer, if it's -18C or lower

Breast milk that's been cooled in the fridge can be carried in a cool bag with ice packs for up to 24 hours.

Storing breast milk in small quantities will help to avoid waste. If you're freezing it, make sure you label and date it first. 

Defrosting frozen breast milk

Breast milk that's been frozen is still good for your baby and is better than formula milk.

It's best to defrost frozen milk slowly in the fridge before giving it to your baby. If you need to use it straightaway you can defrost it by putting it in a jug of warm water or holding it under running warm water.

Once it's defrosted, use it straightaway. Don't re-freeze milk that has been defrosted.

Warming breast milk

You can feed expressed milk straight from the fridge if your baby is happy to drink it cold. Or you can warm the milk to body temperature by placing the bottle in lukewarm water.

Don't use a microwave to heat up or defrost breast milk as it can cause hot spots, which can burn your baby's mouth.

Breast milk if your baby is in hospital

If you're expressing and storing breast milk because your baby is premature or ill, ask the hospital staff caring for your baby for advice on how to store it.

Read more information about breastfeeding a premature or ill baby.

Having difficulty expressing?

If you are finding it difficult or uncomfortable to express your breast milk:

  • Ask your midwife or health visitor for help. They can also tell you about other breastfeeding support available near you.
  • Call the National Breastfeeding Helpline on 0300 100 0212 (9.30am-9.30pm daily).  

Last Updated: 13/06/2023 11:39:14
The information on this page has been adapted by NHS Wales from original content supplied by NHS UK NHS website nhs.uk