We have some Wyandottes and they all lay rather elongated eggs. The only problem I can think of is hatching from those eggs Chickenfan. I read you shouldn't hatch elongated eggs and later realised that it might be because they form double air sacs?
I had a thought that it may be due to some constriction in the oviduct Chickenfan. In which case that might be bad news. She's not unusually fat is she, because that constricts the oviduct as well and usually stops them laying altogether?