In my earlier post ‘Happy twogether fourever? Developing Tolerance for uninvited guests’, I mentioned about the incredible case of Lydia Fairchild, who nearly had her children taken away from her because of failing repeated maternity tests.

In this report by ABC News, Fairchild recounts the nightmare of having to prove in court that she indeed was the biological mother of the children she had given birth to. Thanks to the resolve of her lawyer, who found a similar case that happened years earlier, Fairchild’s ordeal finally came to an end. But only after the discovery of the no less shocking news that she was actually her own twin, who was the – genetic – mother of her children.

Another baffling case of chimerism is that of an Indian man whose belly looked like it was about to explode, but who turned out to be ‘pregnant’ with his own twin who had been growing inside of him. The surgeon who operated on this man to remove what he thought must be an enormous tumor, got the shock of his life when he found a hand shaking his hand inside the man’s belly…

The documentary The twin within the twin deals with a very rare and dangerous condition called twin-twin transfusion syndrome or TTTS (unfortunately, the video is no longer available on youtube). In TTTS one of the twins is getting too little blood, whereas the other one is practically drowned in blood. Very often one, or both, of the twins die in the womb.

One of the reasons why pregnancies of twins are more risky than pregnancies of a single fetus, is that twins need to compete with each other for the blood and nourishment they get from their mother. A fight for life that often ends fatally for one of the twins, if you consider that apparently around one in eight of us actually started our lives as part of a twin.

(image: still from the documentary The twin within the twin)