Double Yolk in Chicken Eggs

I’ve noticed that some chicken eggs have two yolks in them. How does this happen and does it say anything about egg quality?

It happens again and again that a hen’s egg contains two yolks. However, this says nothing about the quality or production conditions of the egg. The development of double yolks usually depends on the age of the laying hens. In young animals, the process of egg formation must first settle down hormonally. They repeatedly lay eggs in which two yolk balls have migrated from the ovary into the fallopian tube, where they have been “packaged” into a single egg.

Since eggs with two yolks are usually larger, experience has shown that double-yolk eggs are more common in packs of L or XL eggs. Even those who buy eggs directly from the farmer or at the weekly market from smaller producers are more likely to get the double-yolk variant. The egg batches here often come from hens of the same age group or the eggs with two yolks were not sorted out in advance for further industrial processing.