The twins were delivered by caesarean section at London's University College Hospital last Wednesday with a combined weight of 4.8kg. They were joined from the breastbone to the top of the navel and had a shared liver but separate hearts.
The operation to separate them was carried out as an emergency when on Tuesday morning doctors found their shared intestine was blocked, a condition which could have killed them both. The 11-hour operation went according to plan but sadly Hope died shortly afterwards with her parents by her bedside.
"Doctors had hoped to wait until the twins were older and stronger to operate, but Prof Pierro said his team had to begin surgery on Tuesday because of a "sudden deterioration" in the children's health".
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