Egg abnormalities and deformed chicken eggs occur with almost every breed of hen at some point in her egg laying career. Eggs laid by non-commercially bred hens vary considerably in size, shape, and color.
My oldest chicken is eight years old. She still manages to pop out a handful of eggs a year, but they’re usually wrinkled and a bit misshapen with thin shells. She certainly isn’t winning any awards for egg production and we can’t rely on her for breakfast any longer!