I have given transfusions to children of Jehovah's Witness children. Virtually all of the parents consented tacitly by not opposing the court orders we obtained in order to give the transfusions. I never felt bad about that until I visited a web site which refers to JW teaching on the subject as "moronic"
That made me more uncomfortable than you might think, given that I believe they are misinterpreting the scripture.
Because I can see a battle coming. If ever there is any successful treatment from embryonic stem cell research, I would refuse that treatment. I would refuse to allow my child to have that treatment - even if it meant that my child would almost certainly die. I believe very strongly that life begins at conception and that destroying embryos for research purposes is a great moral evil.
I still think that the Jehovah's Witnesses are misinterpreting the scripture. If a child's life is in danger, and if we can get a court order for a transfusion, I'll still give it. I will have a great deal more sympathy for those parents, though.