Why are Babies Born with Blue Eyes?

Most babies in the United States are born with blue eyes. Interestingly, only 1 in 5 Caucasian adults grow up to have baby blues. So, why are babies born with blue eyes? It has to do with the amount of melanin they have and how much it increases after birth. This is different for each baby. 

What is Melanin? 

Melanin is a pigment that darkens the eyes, hair and skin. When babies are born, they don’t have melanin in their irises yet. However, they develop more melanin in their first weeks and months of life. This is why you’ll see the blue eyes change. 

A small amount of melanin in the eyes makes them appear blue. A medium amount makes them appear green or hazel, and a lot of melanin makes the eyes brown. Eye color typically isn’t set until 1 or 2 years old because this is when the melanin has reached its peak. 

Eye Color and Genetics 

Having blue eyes at birth has nothing to do with genetics. Many babies, even those of non-white ethnicities, are born with blue eyes. However, genetics play a role in what eye color the baby will end up with. But, it’s not quite as cut-and-dry as you might have learned in science class. 

-Two blue-eyed parents are likely to have a blue-eyed child, but it won’t happen every time.

-Two brown-eyed parents are likely to have a child with brown eyes, but again, this won’t happen every time.

-If one of the grandparents has blue eyes, the baby’s chances of having blue eyes increase.

-If one parent has brown eyes and the other has blue eyes, the child has a 50/50 chance on either eye color.

Most of the Time, Blue Eyes Darken 

When a baby is born with blue eyes, it has to do with the fact that very little melanin has built up. Over the first few days, weeks and months of life, the baby’s melanin will increase and affect eye color. Whether the baby’s eyes stay blue depends on genetics, such as having a parent or grandparent with blue eyes. 

If, however, your child has two different eye colors, they could have a condition called heterochromia iridis. This condition is rare and usually nothing serious. It’s typically a color quirk that was caused when the eyes were formed. Still, it’s important to get it checked out by a retina specialist in NYC. 

No matter what color a baby’s eyes turn out to be, we can all agree that their health matters most!