CO monitoring in pregnancy 

Carbon monoxide (CO) is produced when tobacco products are burnt. It is found in inhaled, exhaled and passive smoke. CO can also be produced by exhaust fumes or emitted from malfunctioning or poorly ventilated fossil or wood fuelled heating and cooking appliances.

Exposure to CO is especially dangerous during pregnancy because it deprives the baby of oxygen, slows its growth and development, and increases the risk of miscarriage, stillbirth and sudden infant death.

Your CO levels will be taken throughout your pregnancy at each routine antenatal appointment. You will be asked to blow into a hand-held machine, called a CO monitor.

The CO monitoring machine will measure the level of CO in your body, the more you have inhaled the higher the reading will be.

Yorkshire SmokeFree has produced a video on the effect of smoking and carbon monoxide in pregnancy and using a carbon monoxide monitor.