Scientists captured high definition images of fetuses in the womb to observe the differences in prenatal development behavior in smokers vs. non-smokers.
The small pilot study involved 20 pregnant women, 16 non-smokers and four smokers, and all were given ultrasounds to monitor fetal activities at 24, 28, 32, and 36 weeks.
Fetuses of smoking mothers touched their faces and had an activity with their mouth more intense than those of non-smoking mothers, according to the study authors.
In the early stages of pregnancy, fetuses touched themselves and moved within the womb, but their movement decreased in intensity in later stages, said lead researcher Nadja Reissland of Durham University in the United Kingdom.
She added that all fetuses had a healthy birth weight but the images showed that smoking affected “fine grain behaviors.”
“Normal fetal behavior shows fewer movements but the images suggest that fetuses in smokers are less mature in their behavior,” Reissland told USA TODAY Network.
The rates of smoking among pregnant women have fallen in the U.S., yet 13.8% of pregnant women still smoke, according to CDC.
Reissland says she wants to replicate the results in a larger study with 60 smokers and 60 non-smokers. She hopes the study will one day be a common practice to show mothers and families the effects of smoking on fetuses in the womb.
“Some research on smell and fetuses can smell different smells and are attracted to smells in the womb so they could be already getting used to the smell of tobacco,” Reissland says.
The findings were published in journal Acta Paediatrica.