Scientists at Otago University have discovered that smoking by women during pregnancy damages DNA in their placenta.
It has long been known that women who smoke are more likely to have children with lower birth weights and a higher risk of serious complications and scientists at Otago University have now discovered why that happens.
They found women who smoked had severely damaged DNA in the cells that transfer nutrients and hormones from the placenta to the baby.The mechanisms which normally repair damaged DNA were also affected.
The researchers say women who quit smoking at least four weeks before giving birth had less damage. Their next step will be to investigate whether smoking also damages DNA inside the cells of unborn babies.