Passive smoking in pregnancy

If you share a home with a smoker then you'll be breathing in over 4,000 toxic chemicals which are released into the atmosphere both by the burning tip of a cigarette (known as sidestream smoke) and by the smoker exhaling cigarette smoke around you (known as mainstream smoke).

These include:

• tar
• carbon monoxide
• benzene
• ammonia
• formaldehyde
• hydrogen cyanide

Harm to you and your child's health

Several major reviews of the evidence have been produced since 2000, confirming that passive smoking can lead to a range of health problems. It's been estimated that 17,000 children under the age of five are admitted to hospital every year in the UK as a result of illnesses resulting from passive smoking.

Harm starts in the womb

Your unborn child is already at risk from passive smoking. If you're exposed to cigarette smoke while pregnant then there's an increased risk of:

• miscarriage
• ectopic pregnancy
• premature birth
• bleeding and placental problems
• your child being born underweight, which in turn increases the risk of a variety of conditions, from infection to feeding problems
• your baby having a small head circumference

Once your baby is born passive smoking increases the risk of:

• sudden infant death syndrome (cot death)
• poor lung function and respiratory problems, including asthma, bronchitis and pneumonia
• infections of the middle ear (glue ear)
• potential harm to learning and behavioural development, including disorders such as attention deficit/hyperactivity disorder (ADHD)
• meningococcal infections
• childhood cancers and leukaemia
• respiratory disease when they are an adult

Adults are at risk too

Adults exposed to passive smoking are, of course, also at risk from all the problems associated with tobacco smoke. For example, the risk of lung cancer among non-smokers living with smokers is increased by up to 30 per cent. The risk of heart disease may also increase by the same amount.

Avoid smoking in the home

If a smoker really wants to quit, then they stand a better than average chance of being successful. But for the best chance, they need to be part of a proper ‘quit smoking’ programme which will include counselling, or psychological support, as well as nicotine replacement treatments such as gum or patches. With this sort of programme they have about a one in three chance of giving up. GPs will refer them to their local quit smoking clinic, often within their own health centre or surgery, where they can get free help on the NHS.

If someone is unable to quit, smoking outside the home, in the garden or at work is a better option. If they must smoke in the house, restrict it to one room away from the baby and never breathe cigarette smoke on to a child.

Action on Smoking & Health (ASH) can provide a very detailed summary of the evidence against passive smoking at www.ash.org.uk.