Created using a 4D ultrasound scan, the image above appears to show a baby leaning over to kiss her twin sister.
The new 4D scan uses the same frequency of sound waves as in a normal ultrasound. But the sound waves are directed from many more angles, producing a 'real-time' video of the foetus as it moves and allowing scientists to say the images are in four dimensions.
This advanced technology has allowed scientists to capture the development of foetuses like never before, including twins and triplets jostling for space in the womb while grasping each other's hands and even faces.
The images have also allowed scientists to create life-size silicone models and astonishing computer-generated images of the multiple foetuses.
View more images here.