Smoking While Pregnant Affects Baby's Motor Skills

Women who smoke during pregnancy risk affecting their child's coordination and physical control, says a new Swedish study, carried out by researchers at Örebro University.

The research followed over 13,000 children taking part in the National Child Development Study, all born in the United Kingdom, the same week in March 1958, and through their entire life.

Their mothers' smoking habits were also recorded and at the age of 11 years, the children underwent tests by a school doctor, to verify their physical control and coordination.

All children had to do simple tasks like picking up 20 matches against time, with their left and right hand, tick up to 200 squares against time and copy a simple figure.

Scientists noticed that children whose mothers smoked at least nine cigarettes a day while they were pregnant, had more difficulties succeeding the tests, especially if they had to use their non-dominant hand (the left hand for the majority).

Professor Scott Montgomery at Örebro University said that they also discovered that boys seemed to be more affected than girls.

“There is a link between nicotine and testosterone,” says Matz Larsson, researcher in medicine and consultant physician at Örebro University Hospital.

“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.”

There are several reasons behind the fact that women who smoke during pregnancy risk having a child with motor ability problems.

Larsson says that “nicotine interacts with acetylcholine, which is an important neurotransmitter and messenger when the brain is developing during the fetal stage, but it might also be the case that the mother's smoking leads to a form of fetal malnutrition.”

“We believe this is an interesting study as it is based on physical tests rather than cognitive, which are dependent on, for example, elements of learning,” adds Scott Montgomery.

This means that these results are less likely to be influenced by social and economic factors and even after checking for several other factors, the difference in motor abilities remained even.

This research sheds a light on the reason why neurological function in childhood is linked with adverse health outcomes in later life like obesity and type 2 diabetes, because these are also associated with maternal smoking during pregnancy.

This study is published in the Journal of Epidemiology and Community Health.