Carbon monoxide (CO) is a colourless, odourless and tasteless poisonous gas.

CO is found in exhaust fumes, faulty gas appliances, coal/wood fires, oil burning appliances and cigarette smoke.

Breathing in CO during pregnancy limits the amount of oxygen and nutrients getting to your baby.

This increases the risk of stillbirth, low birth weight, premature birth, and miscarriage.

You will be asked to blow into a CO monitor at various points throughout your pregnancy to ensure your baby is getting the oxygen they need.

Readings above 4ppm (parts per million) show you have a more harmful level of CO in your body, which may be from smoking, breathing in someone else’s smoke or a faulty gas appliance, so we’ll work with you to plan how to bring your reading down.

If you smoke, just let us know – we know it can be hard to stop and no-one is judging you. We will refer you to our specially trained Tobacco Dependency Treatment Team, who are here to support you with free medication and behavioural therapy. This will help to manage any cravings and keep you comfortable, whilst also improving your baby’s health.

They will also help anyone who lives in your house to quit if they want to support you and stop smoking at the same time.

CO levels are affected directly by smoking, passive smoking (if someone in your house or car smokes) exhaust fumes and poorly ventilated household appliances.

Swap and Stop Stories

Sarah Wise | Consultant Midwife

The NHS Tobacco Dependency Treatment advisors are a huge help to the maternity team and service users. If you smoke, the very best thing you can do for you and your baby is to swap to a safer form of nicotine or ideally quit compl …

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