Scans showing movements in a fetus whose mother is a smoker (top) and a fetus whose mother is a non-smoker (below). Source: Durham University

RESEARCHERS IN THE UK have suggested the harmful effects of smoking during pregnancy may be seen in the facial movements of the unborn babies.

A study conducted by researchers at Durham and Lancaster universities observed 4-d ultrasound scans of 20 fetuses, looking at mouth and touch movements, with scans taken at four intervals between 24 and 36 weeks of pregnancy.

Four belonged to mothers who smoked an average of 14 cigarettes a day and the remaining mothers were non-smokers. All babies were healthy when born.

However during their development, researchers found fetuses whose mothers were smokers showed a significantly higher rate of mouth movements than the normal declining rate of movements expected in a fetus during pregnancy.

They have suggested that the reason for this might be that the fetal central nervous system, which controls movements in general and facial movements in particular, did not develop at the same rate and in the same manner as in fetuses of mothers who did not smoke.

Source: Durham University

There was also a bigger delay in the reduction of facial touching by fetuses whose mothers smoked, but researchers said this was less significant.

Like previous studies, this one also showed that maternal stress and depression have a significant impact on fetal movements, but that the increase in mouth and touch movements was even higher in babies whose mothers smoked.

“Technology means we can now see what was previously hidden, revealing how smoking affects the development of the fetus in ways we did not realise,” commented co-author, Professor Brian Francis of Lancaster University. “This is yet further evidence of the negative effects of smoking in pregnancy.”

The research is published in the journal Acta Paediatrica.

Read: Women smoke to ‘deal with stress of pregnancy’>

Read: How to get pregnant women to quit smoking? Pay them>