Chicken egg with no shell

Sometimes the older hens will struggle to make shells. When they lay one without a shell it's very hard on the birds. They often die soon after laying one like this.

There is no shell at all on this egg. Only the flexible membrane holds the contents together. I set eggs to hatch today so I had the egg candling light out and back lit this shot with it. I have no idea which one laid this egg and everyone appears in tip top condition just now. We have a glut of eggs.