Contagious yawning begins in the WOMB, experts reveal - as foetuses are seen copying their mothers' mouth movements

There's nothing quite as contagious as a yawn – and it turns out even babies in the womb aren't immune. Experts have discovered foetuses'catch' yawns from their mothers and have been seen slowly opening and closing their mouths. As part of a study, they recorded the facial expressions of pregnant women while an ultrasound machine captured real-time images of their foetuses' faces. By comparing the two records, the researchers found that foetuses were more likely to yawn after their mothers did, with a delay of around 90 seconds. They said yawning may change the mother's breathing, chest pressure and diaphragm movements, which could provide physical cues the foetus detects.