Here's another reason to stop smoking when pregnant! The Aarhus University study has been published in the American Journal of Epidemiology. We found that children of mothers who had smoked more than ten cigarettes a day during pregnancy on average entered puberty three to six months earlier than the children of non-smokers says Nis Brix who is one of the researchers behind the study. Early puberty can be associated with an increased risk of a number of diseases as an adult such as obesity diabetes cardiovascular diseases and certain types of cancer said Nis Brix. Brix hopes that the study's