The findings are the first to show that it is possible to explore visual perception and cognition in babies before they are born, researchers said.
"We have shown the foetus can distinguish between different shapes, preferring to track face-like over non- face-like shapes," said Vincent Reid of Lancaster University in the UK.
"This preference has been recognised in babies for many decades, but until now exploring foetal vision has not been attempted," said Reid.
Scientists had also realised that it is possible for light to penetrate through human tissue and into the uterus, where a foetus could see it.
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The researchers tested the responses of 39 foetuses to face-like patterns of light presented to them in both upright and inverted orientations.
The projected light moved across their field of vision while researchers watched the foetuses' reactions using 4D ultrasound.
Those ultrasound movies showed that the developing babies turned their heads to look more often at face-like stimuli that were upright than those that were presented to them upside down.
"If this was the case, we would have seen no difference in how they responded to the upright and upside-down versions of the stimuli. But it turned out that they responded in a way that was very similar to infants," he said.
The findings suggest that babies' preference for faces begins in the womb. There is no learning or experience after birth required.
The findings also confirm that foetuses have enough light to see and have visual experiences in the womb. However, Reid said that he discourages pregnant mothers from shining bright lights into their bellies.