The judges were told that the 20-year-old woman - suffering complications following the still birth of her baby - remained in a 'critical but stable' condition. She is not a Jehovah's Witness.
Full reasons for the decision will be given next week. The case is the first in English courts to question the circumstances in which an adult can express a 'constitutional right to die'.
Although Lord Donaldson, Master of the Rolls, and Lords Justice Butler-Sloss and Staughton gave no hint on which grounds they were prepared in effect to overrule the woman's written refusal of blood, their judgment is expected to contain guidelines that doctors should follow when faced with patients' refusals of life-saving treatment.
The judges were being asked to declare her treatment lawful and in the woman's best interest, after claims that her mother exerted an undue influence over her when she was in turmoil and vulnerable. They were also asked to rule that her refusal of blood was invalid because doctors had not informed her of potential dangers and misled her as to the availability of alternatives.
The courts were called on to intervene by the father of the woman - identified only as 'T' - when her condition in hospital deteriorated and she needed a life-saving transfusion.
The father, who is divorced from her mother, does not share his former wife's religion, which forbids any medical use of blood, including transfusions, even when it can result in death. Last week he won a High Court ruling that his daughter could be treated and she was given two units of blood.
Mr Justice Ward then ruled that her refusal of blood, given when she was not at risk, did not cover the unforeseen emergency which caused her condition to deteriorate. He was critical of the mother, saying: 'The pressure of her mother, the very presence of her mother, the mother's fervent belief in the sin of blood transfusion, the patient's desire to please her mother despite their troubled relationship: all this contributed to the focus of attention being drawn to blood transfusion before anyone else had ever contemplated its need.'
He said there was no evidence that the convictions of 'T' were so deep-seated or fundamental so as to constitute 'an immutable decision as to her way of life - or her way of death'.
But his ruling was challenged on behalf of 'T' by David Venables, the Official Solicitor, who was called in to represent her interests when she became unconscious.
James Munby QC, for Mr Venables, argued that 'T's wish not to have blood transfusions had to come first. He said: 'The concept of self-determination entitles the patient to act in a way which others, even society at large, might think to be misguided, irrational, absurd or even worse.'
After yesterday's ruling, Mr Venables said he would wait for the full judgment before deciding whether to take the case to the House of Lords. He said: 'The judges have concluded that Mr Justice Ward, in overriding what seemed to be the woman's wishes, in the particular circumstances of this case was correct. But equally, if you look at Mr Justice Ward's judgment, it does not knock down the principle that people have the right to refuse treatment.'Reuse content