What Causes Wrinkly Eggs?

You’re collecting your hens’ eggs for the day when you notice something you’ve never seen before: a wrinkly egg. While not particularly common, wrinkled eggs can occur especially from older layers. Understandably, chicken owners will have plenty of questions about these wrinkly eggs and what causes them. Thankfully, we have answers.

Infectious Bronchitiswrinkly eggs

Infectious bronchitis is a viral disease that causes respiratory disease and kidney damage and can be fatal for chickens. It can also cause your hen to lay wrinkled eggs even years after the infection. This is because infectious bronchitis can cause oviduct infection in adult hents, which in turn produces wrinkled eggshells. Plus, since hens can carry this disease for life, they can produce wrinkled eggs years after they were first infected.

Thankfully, you can prevent this from happening by getting your flock vaccinated against infectious bronchitis.


Your hen has never had infectious bronchitis, yet it is still producing wrinkly eggs. If this is the case, then the wrinkled eggshell was likely caused by stress. If the hen is startled or stressed while laying (such as by a thunderstorm or predator), the shell can end up with a ridged or wrinkled surface. Heat stress can also cause wrinkly eggs, as well as poor nutrition.


When a human ages, wrinkles show up on our faces. When a hen ages, those wrinkles can show up on their eggs. As a hen gets older, the albumen (or whites) of their eggs will become thinner. This makes it more difficult for the shell to encase the egg, resulting in bumps and ridges.

While wrinkled eggs are not pretty to look at, they are nevertheless safe to eat, provided the shells are not cracked or broken. For futher questions on wrinkly eggs and chicken care, contact Chickens for Backyards today!