Researchers from the the University of Durham have captured fetuses yawning in the womb using 4D ultrasound scans. 4D is the term for a 3D image of the foetus moving in real-time.
For a long time, some scientists have argued that fetuses simply open their mouth and do not yawn.
With these new scans, British researchers say they can tell the difference, and that more than half of the 15 fetuses recorded on video were yawning. Yawning, in turn, provides clues about the health of an unborn baby.
The findings were published Wednesday, Nov. 21, in the journal PLOS One.
The footage below was caught by Dr. Wolfgang Moroder and shows a foetus at 30 weeks.
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