It's not exactly bombshell news that smoking during pregnancy probably means bad news for the baby, but the CDC estimates that about 14% of pregnant women in the US still light up anyway. Researchers hope their new study shrinks that number even more, reports USA Today. Using high-definition images of fetuses, they found that those inside smokers touched their faces and moved their mouths significantly more than those in non-smokers. That kind of movement isn't a good sign, because healthy fetuses generally stop such activity over time. The study, then, suggests that "mothers who smoke may delay the development of their babies’ central nervous systems," explains the Independent.
The researchers compared fetuses in 20 women, four of whom smoked, and took four sets of 4D ultrasound scans between 24 and 36 weeks. "Normal fetal behavior shows fewer movements, but the images suggest that fetuses in smokers are less mature in their behavior," says lead researcher Nadja Reissland of the UK's Durham University. The team will next use a larger sample of women to see if they can replicate the findings. Researchers also found increased movement in fetuses of women who were stressed or depressed while pregnant, but the association wasn't as strong as with smokers, reports Medical News Today. (Click to read about the bizarre case in which a girl was born pregnant.)