How often should i sterilize baby bottles

4-minute read

It’s essential to properly wash and sterilise the feeding equipment when you’re bottle feeding. You'll need to clean and sterilise each bottle, teat and screw cap after every feed. It’s important that you continue sterilising everything until your baby is 12 months' old.

Why is it important to clean and sterilise my baby’s bottles?

Babies have immature immune systems so they aren’t strong enough to fight off a range of infections. One important way to support them in staying healthy is to reduce the chances of their getting sick in the first place.

Milk is the perfect medium in which bacteria can grow. This is why it’s important to sterilise all feeding equipment and keep formula cold until just before feeding your baby.

What equipment needs cleaning and how often?

You need to clean and sterilise all bottle parts, teats and screw caps.

1. Separate all parts of the bottle and pull the teat out of its screw cap.
2. Use hot water and dishwashing detergent.
3. Clean all areas of the bottle with a bottle brush, including the thread where the cap screws on.
4. Remove any milk still sitting in the teat or the hole with a teat brush.
5. Squeeze hot, soapy water through the teat hole, then do the same with clean water to rinse the teat.
6. Make sure to rinse the bottles and equipment well.

Get a new bottle brush once the bristles are worn. They need to be stiff enough to remove all the milky residue from the inside of the bottle.

How to sterilise feeding equipment

Even if bottles and teats look clean, they might still carry germs to your baby so it’s essential to sterilise your feeding equipment properly.

There are 3 ways to do this: boiling, steam sterilisation and chemical sterilisation.

If you’re breastfeeding and only need to sterilise a bottle occasionally, the boiling method may be good enough. It’s also cheaper than buying a steam steriliser. If you’re expressing and/or bottle feeding, then a steam steriliser might be the best option.

The boiling method

1. Put all parts of the cleaned bottle, including teats, in a large saucepan.
2. Cover the equipment with tap water.
3. Make sure all air bubbles are out of the bottles and that they are fully submerged under the water.
4. Bring the water to the boil.
5. Boil for 5 minutes.
6. Let the feeding equipment cool in the saucepan before taking it out.
7. Place all the feeding equipment in a clean container and put it in the fridge. Make sure the container is covered firmly with a lid.
8. You can store everything in the fridge for up to 24 hours.

The steam sterilisation method

Steam sterilisers are popular because they work quickly, are cheap to use and are very effective. They heat water to boiling point and the steam kills the bacteria. Some steam sterilisers are designed to operate in a microwave.

1. Place the clean bottles and feeding equipment in the steriliser.
2. Make sure there’s enough room between each bottle, teat and screw cap for the steam to circulate around all surfaces.
3. Follow the manufacturer’s directions about how much water to add.
4. Turn on and push the button to start. If you’re using a microwave steriliser, place the steriliser in the microwave and turn on for the correct time.
5. Wait until the sterilisation cycle has finished and the light goes off.
6. Store all sterilised feeding equipment in a clean, lidded container in the fridge.
7. Sterilise all equipment again if you haven’t used it within 24 hours.

The chemical sterilisation method

Be careful when using chemical sterilisation. Many methods use bleach, which can also bleach clothing and surfaces, and irritate the skin, if spilt.

Antibacterial chemical sterilisation solutions are available in liquid and tablet form. They need to be prepared exactly as directed on the container.

1. Make sure you have a container that’s large enough to hold your baby’s bottles and feeding equipment.
2. Use the recommended amount of tap water to prepare the sterilising solution.
3. Submerge all bottles and feeding equipment in the solution. Make sure there are no bubbles left in the bottles.
4. Leave the equipment in the solution for the recommended time – there’s no need to rinse the solution off after sterilisation.
5. Throw out the solution after 24 hours and wash out the container before preparing a new batch.

Wash your hands before handling sterilised feeding equipment

Make sure you wash and dry your hands before you handle sterilised bottles and teats. It’s easy to contaminate equipment just by touching it with unclean hands.

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Last reviewed: September 2020