How smoking harms the unborn baby
Babies born to mothers who smoke:

* are more likely to be born prematurely and with a low birth weight (below 2.5kg or 5lb 8oz).
* have a birth weight on average 200g (7oz) less than those born to non-smokers. This effect increases proportionally - the more the mother smokes, the less the child weighs.
* have organs that are smaller on average than babies born to non-smokers.
* have poorer lung function.
* are twice as likely to die from cot death. There seems to be a direct link between cot death and parents smoking.
* are ill more frequently. Babies born to women who smoked 15 cigarettes or more a day during pregnancy are taken into hospital twice as often during the first eight months of life.
* get painful diseases such as inflammation of the middle ear and asthmatic bronchitis more frequently in early childhood.
* are more likely to become smokers themselves in later years.

Sources:
http://www.netdoctor.co.uk/health_advice/facts/pregnantsmoking.htm

Tatarov Anton