JW belief regarding blood:
Ge 9:4
But flesh with the life thereof, which is the blood thereof, shall ye not eat.
Le 17:14
4For it is the life of all flesh; the blood of it is for the life thereof: therefore I said unto the children of Israel, Ye shall eat the blood of no manner of flesh: for the life of all flesh is the blood thereof: whosoever eateth it shall be cut off.
&
Le 7:26-27
26Moreover ye shall eat no manner of blood, whether it be of fowl or of beast, in any of your dwellings. 27Whatsoever soul it be that eateth any manner of blood, even that soul shall be cut off from his people.
Ac 15:28, 29
28For it seemed good to the Holy Ghost, and to us, to lay upon you no greater burden than these necessary things;
29That ye abstain from meats offered to idols, and from blood, and from things strangled, and from fornication: from which if ye keep yourselves, ye shall do well. Fare ye well.
&
Acts 21:25
25As touching the Gentiles which believe, we have written and concluded that they observe no such thing, save only that they keep themselves from things offered to idols, and from blood, and from strangled, and from fornication.
As you can see, these passages clearly
forbid blood transfusions to save human lives

(I am being sarcastic, if you haven't guessed)
JWs, Jews, and Muslims are all the same! (You can throw in all cults for that matter)