Exposure of children to tobacco smoke has always been associated with increased risks of asthma and allergies. A news study presents data supporting that smoking during pregnancy or short after the birth of a child indeed increase the baby's chances of developing allergy and asthma.

The study showed that children of mothers who had smoked while pregnant ran double the risk of developing asthma before the age of four. There was also a clear correlation between the number of cigarettes smoked and the risk of developing asthma.

In addition the study also showed that four-year olds who were exposed to tobacco smoke when they were two months old had IgE antibodies (allergy antibodies) against one or more allergens in the blood more often than their coevals from non-smoking homes. The strongest correlation was observed for antibodies against cat allergens, which were twice as common in these children.