Fetuses yawn in the womb, according to new research

We know that unborn babies hiccup, swallow and stretch in the womb but new observational research concludes that they also yawn. The 4D scans of 15 healthy fetuses, by Durham and Lancaster Universities, also suggest that yawning is a developmental process which could potentially give doctors another index of a fetus' health. The study is published today in the prestigious international academic journal, PLOS ONE. It was funded by the Economic and Social Research Council (ESRC). While some researchers have suggested that fetuses yawn, others have disagreed and claim it is simple mouth opening. But the new research clearly distinguished 'yawning' from 'non-yawn mouth opening' based on the duration of mouth opening. The researchers did this by using the 4D video footage to closely examine all events where a mouth stretch occurred in the fetus.