A recent study suggests that children whose mothers smoked during pregnancy have lower high-density lipoprotein (HDL) levels, also known as the “good” cholesterol. This raises children’s risk of suffering from heart attack and stroke later in their life.

The study, which was carried out by Australian researchers, has 405 participants at the age of 8 and in good physical shape. The researchers discovered that those children whose mothers smoked during pregnancy had good cholesterol levels of about 1.3mmol/L, which is below the normal level of 1.5mmol/L observed in children born to non-smoking mothers.

David Celermajer, a cardiology professor at the University of Sydney and lead author of the study, said in a journal news release that the results of the study suggest that smoking during pregnancy marks a set of unhealthy characteristics on children while they are still developing in the mother’s womb. He said the characteristics last for a minimum of eight years and longer.

Published in the European Heart Journal on June 21, the study reports that the result was independent of whether the kids were exposed to cigarette smoke after birth. It suggested that prenatal exposure still had the greatest impact on subsequent effect.

Celermajer and his colleagues noted that the rates of maternal smoking are still high. In most Western Nations, there are about 15 percent smoking pregnant women. This means the results of their study could be beneficial in the efforts to prevent heart problems.

Children whose mothers have smoked during pregnancy should be observed carefully for other heart risk factors such as high blood pressure, smoking and high levels of LDL or “bad” type of cholesterol, Celermajer said.