Scientists have more proof that smoking by a pregnant woman can harm her developing baby. This time it’s an international study led by University of Iowa pediatrician Jeff Murray. Murray says this project looked at whether genes and the environment work together to cause a defect called cleft lip and palate, and they found doing the study that smoking by the mother greatly increased the risk of developing that defect.
Murray’s team looked at pregnant women who smoke fifteen or more cigarettes a day and says they are 20-times more likely to give birth to a baby with a cleft palate deformity. Murray says they don’t know the specific biological mechanism isn’t yet understood. He says smoke does contain many toxic byproducts and Murray says if the fetus isn’t able to break down the byproducts, it puts them at increased risk for developing the cleft.
The smoke’s not the only factor at fault, though — Doctor Murray says the defect showed up in fetuses that had a certain genetic makeup.
He says there’s a genetic basis for which of the affected babies were unable to break down the toxic chemicals in their mothers’ blood.
The study by Doctor Murray and researchers in Denmark is published in the American Journal of Human Genetics.