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How to express breast milk

By Anna Studman

Expressing breast milk can take some getting used to. Find out why it's worth it, different ways you can do it, and how to store breast milk.

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Why express breast milk?

There are several reasons to express milk, including:

  • Your baby can still be fed breast milk when you're not there – for example, if you go out or return to work. Read our guide on returning to work.
  • If your baby is ill or premature, they may not be able to feed from your breast at first.
  • It allows dads to get involved in the feeding process.
  • Expressing milk can relieve uncomfortably full breasts.
  • If you're breastfeeding, expressing milk helps to maintain your milk supply.
  • If you're not able to breastfeed, your baby still gets the benefits of breast milk.

Browse our breast pump reviews to find the breast pump that's best for you. 

How to express milk

Hand expressing milk

Some mums find it easier to express milk by hand rather than using a breast pump, while others find it tricky to get the hang of. It's down to your individual preference – here are some tips from the NHS to help you get started:

  • Wash your hands thoroughly with soap and warm water.
  • Squeeze gently using your thumb and the rest of your fingers in a C-shape.
  • Gradually build up a rhythm – change breast or shift position when the milk flow slows down or stops.

Manual breast pumps

Alternatively, a manual breast pump makes expressing milk a quicker, easier process for some mums. They're lightweight, low cost and quiet – but can be tiring to use for long periods. Discover the pros and cons of manual breast pumps in more detail.

Electric breast pumps

Electric breast pumps are generally more powerful and durable than manual breast pumps – but, unless you buy a battery-operated one, you'll need access to a plug socket. Find out exactly how an electric breast pump works, and see if it’s the right choice for you.

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Hospital-grade breast pumps

Hospital-grade breast pumps from companies, such as Medela or Ameda, are larger, more powerful machines. If you have to stay in hospital for longer than usual, you may use one there. Once you're home, you can hire one on a monthly basis from the NHS or the National Childbirth Trust (NCT), a UK parenting charity.

Does expressing milk hurt?

Expressing or pumping breast milk shouldn't be painful, but it can be uncomfortable until you become used to it. Some women find expressing milk helps to relieve the discomfort caused by overly full breasts. If you do experience any pain on your nipple when expressing using a breast pump, check that you're using the right size of nipple shield.

The NHS offers expressing milk and breastfeeding advice, as do the NCT and La Leche League, a support network for breastfeeding mums.

How should I store breast milk?

Breast milk can be expressed in advance and then stored in a fridge or in a freezer. Any collection container needs to be sterilised thoroughly, and once the milk has been expressed it should be transferred to the fridge or freezer as soon as possible.

The NHS and NCT say breast milk is safe for up to five days, if stored in a fridge at less than 4°C, or three days at a slightly higher temperature (or if you're unsure of the temperature of the fridge). Breast milk can be frozen for up to two weeks in the freezer compartment of a fridge, or six months in a freezer at minus 18°C.

Many breast pumps come with guides to milk storage in their instructions. For more information on expressing, storing and defrosting frozen breast milk, visit the NCT website or the NHS expressing breast milk guide.


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