I've gotten a few hens over the years that will lay eggs like that. Doesn't seem to be anything wrong with them except the egg is weaker at the crease and breaks easily.
I've read it can be a sign of a respiratory infection, especially if it's temporary.
If the hen lays them consistently than it's probably just something to do with her reproductive tract and how she personally forms eggs. It may be genetic, so I wouldn't hatch her eggs, but they should be fine for eating.