As if you needed another reason to quit smoking — especially during pregnancy — consider that women who puff while pregnant may hobble their babies’ coordination and physical control. The effect may be most pronounced in boys, according to research published in the Journal of Epidemiology and Community Health, because of the connection between nicotine and testosterone. (More on Time.com: AHA: Don’t Be Fooled, Smokeless Tobacco Isn’t Exactly Safe)
“Nicotine can influence development of the brain and interacts with testosterone particularly during the fetal stage, and this could make boys extra susceptible to fetal nicotine exposure,” says Matz Larsson, researcher in medicine and consultant physician at Örebro University Hospital in Sweden.
Larsson and Scott Montgomery, a professor at Örebro, analyzed figures collected from more than 13,000 children participating in the National Child Development Study. The children were all born in Great Britain in the same week in March 1958.
When they turned 11, the children’s physical control and coordination were assessed. They were told to pick up 20 matches using both their left and right hands. They also had to tick up to 200 squares and copy a simple figure. (More on Time.com: Why It’s Harder For Older Women to Have Healthy Babies)
The children born to mothers who’d smoked at least nine cigarettes a day while pregnant had a harder time completing the tasks. “Our findings suggest that women who smoke during pregnancy run the risk of harming the child’s motor ability,” says Matz Larsson. Nicotine influences acetylcholine, a neurotransmitter that acts as a messenger during fetal brain development. But the nicotine could also be contributing to fetal malnutrition, says Larsson.
Tack that on to the laundry list of other woes related to smoking during pregnancy, including lower birth weights, poor fetal growth and increased risk of premature delivery. The U.S. Public Health Service estimates if pregnant women stopped smoking, there would be an 11% reduction in U.S. stillbirths and a 5% reduction in newborn deaths.
For the 10% of women who smoke while pregnant, this is yet another reason to toss out those cigarettes.
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