Strange egg from my 2 year old Buff Orpington

[uh1hhuey]

So I checked my girls eggs yesterday and found this. Anyone understand how this happens, Looks crazy with that almost perfect line cut all the way around it.

Thanks

 

[sourland]

That's pretty neat. Sometimes 'wonky' eggs indicate an upcoming break in the laying cycle. Other times they indicate a reproductive tract problem, but generally they 'just happen'.