I've not tried this on a quilt, but I can speak from experience that hydrogen peroxide works wonders if you need to get blood out of your carpet!
I suppose I should tell you why I know this, huh? Ten years ago my daughter had her tonsils out. A few days later some of the stitches came loose. She woke up in the middle of the night spitting up blood. After pounding on our bedroom door at 5 AM to tell us she was spitting up blood, she nearly passed out. By the time I grabbed my robe and got to her there was blood all over my living room carpet and our front entry. My hubby had to carry her to the car for me to rush her to the ER. He stayed behind to clean up the blood. By the time I got home that night, he had every drop of blood cleaned up with the hydrogen peroxide! My daughter was 17 when this happened and had lost so much blood that she needed a transfusion of 2 units before they could take her into emergency surgery to re-stitch her throat. Her BP had dropped down to about 60/39.
Probably not my favorite way to learn how well hydrogen peroxide works.