bloody, soft-shelled egg

I have what I think is an older white leghorn who hardly ever lays and when she does, it's soft-shelled and usually broken by the time I find it. This morning in the litter there was just a shell-less mass (looked like there was a thin membrane with it) with what looked like blood clots mixed in. Does this happen as older hens stop laying? I did a search but didn't really see anything about blood mixed in with the eggs….