A MRI scan taken at the Magnetic Image Resonance scanner at Imperial College, London, shows twins fighting inside the womb.
The scan was taken in order to understand more about a condition called twin-to-twin transfusion syndrome (TTTS). The latter is a serious condition in which one twin takes blood from the other twin, who is called the "donor" twin.
"One of the problems with the imbalances of blood flow is that if you get a sudden shift of blood from one twin to the other, that can cause brain injury," Dr Marisa Taylor-Clarke, who used the scan to study 24 sets of twins with TTTS, told Reuters. "So it can cause stroke or hemorrhage in one or both of the twins' brains. MRI can pick up signs of brain injury much earlier and in much greater detail than ultrasound can at the moment."
In this particular video, the smaller fetus is seen jostling for space and punching the bigger sibling, who dies not react at first. However the latter then knees the smaller fetus to retain its space.
The video is believed to have been taken at 20 weeks of pregnancy, but the identity of the mother or the sex of the fetuses is not known.