A study published in PLOS ONE, suggests that fetuses actually practice their facial expression while in utero.
MedicalXpress noted that the study, which was an eight year project applied FACS, a facial action coding system, used to study adult facial expressions, to the unborn fetuses throughout their development.
The findings were that unborn babies practice making expressions such as crying and smiling as well as pain-like mannerisms, identified by simultaneously furrowing the brow, wrinkling the nose and raising the lip while still in the womb.
The facial images were taken from 4D scans of healthy fetuses. It was noted that smiling happens earlier on in the pregnancy and more complex expressions such as pain which involves multiple muscles evolve around 36 weeks.
Lead Researcher and senior lecturer in developmental psychology at Durham University, Dr Nadja Reissland, noted, “At the moment there is no link between these expressions and emotions”.
However, researchers do believe that rehearsing these facial expressions in utero allows a new born baby to be able to communicate pain or distress to their parents as soon as they are born, which is a necessary life skill.