BERLIN (Deutsche Presse-Agentur) -- Mothers who smoke not only damage their children during pregnancy but can also negatively affect their development in the breast-feeding phase. Nicotine and other dangerous substances contained in tobacco enter breast milk and then the child's system, according to a new report from the German Cancer Research Centre.

The report says the babies of mothers who smoke absorb about seven micrograms of nicotine per kilogram of body weight a day. That is the equivalent absorption rate of an adult who smokes one cigarette a day with a nicotine content level of 0.7 milligrams. Nicotine can also get into the breast milk of non-smoking mothers if they live with a smoker.

It has been observed that if a mother smokes heavily during breast-feeding her baby may appear restless, may vomit, can suffer from colic and weigh too little, according to the report. It may also affect the child's sleep pattern.

Smoking can also negatively affect the level of breast milk produced by the mother and also lead to poor breast-feeding habits. Mothers who smoke have less breast milk than non-smokers, they breast-feed less often and are more likely to stop breast-feeding early the more they smoke.

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