Women who smoke while pregnant risk doing long-term damage to the hearts of their unborn children, animal studies suggest.

Reuters reported May 1 that researchers found that rats given nicotine during pregnancy and shortly after giving birth had offspring that suffered impaired coronary blood flow at age three months.

"Our study shows that prenatal ... nicotine has significant impact on cardiac function of adult offspring," said researcher Lubo Zhang of the Center for Perinatal Biology at Loma Linda University. "The finding supports a very exciting area of research called 'fetal programming of cardiovascular disease.' This occurs not only with nicotine but with many other insults that may occur during fetal development."

Both male and female rats demonstrated heart damage when exposed to nicotine in utero, but the effect on females was more pronounced.

The research was presented at the recent Experimental Biology 2007 meeting, sponsored by the American Physiological Society.