Once your baby is born, you can’t wait to see the shape of his nose, his little mouth and those adorable cheeks, as well as the color of his hair and eyes. You observe all of these unique features and debate about who he looks more like.
One of the most fascinating things about your newborn is definitely the color of his eyes. Babies, especially fair-skinned ones, usually have light-colored eyes when they are born. However, the color of their eyes may change several times within the first year.
So, you must wonder – what is responsible for the transformation in your little one’s eye color? Why and how the color changes depends on the amount of melanin in the iris, which is determined mainly by the genes inherited from each parent.
What Role Does Melanin Play In Baby’s Eye Color?
Melanin is the pigment that is responsible for giving the color to our skin, hair and eyes. And just as sunlight turns the skin darker, it does the same to eye color.
The cells that create melanin respond to light. When babies are born, they have light-colored eyes because they have spent the whole time in the dark inside the womb and they have very little melanin in their eyes. But when a baby’s eyes are exposed to light, melanin production is stimulated and that eventually leads to the eye color darkening or changing over time.
It's important to understand that it's not the color of the pigment that causes the change of color. The only pigment we have in the eye is brown – it’s the amount of that pigment in the iris that determines what color the eyes will be. Consequently, a small amount of melanin will turn a baby’s eye color to blue, green, or hazel; while a lot of melanin will result in brown or black eyes.
When Does Eye Color Change?
Typically, the most dramatic change occurs between the ages of 6 and 9 months. By this time, the iris has usually stored a sufficient amount of melanin so that it is obvious what the final eye color of your child will be. By their first birthday, most babies will have their permanent eye color, although you may notice subtle changes by your child’s third birthday.
These changes always go from light to dark, and not the other way around. So, for example, if your child already has brown eyes, they can only turn darker – don’t expect them to suddenly turn back to blue. What’s more, in about 10% of the population, changes in the eye color can continue all the way up to adulthood.
What Role Do Genetics Play In Baby’s Eye Color?
In general, the color of babies’ eyes depends on the genes they inherit from both parents. However, this process is not that simple because it includes multiple genes working together. And a baby’s eye color does not only depend on the parents’ eye color, but it also depends on whether their genes are dominant or recessive, and whether they are carrying matching genes from their parents (for example, both copies are for brown eyes) or the two copies of genes differ (one for brown and one for blue eyes). This makes it hard to predict the exact color and shade of your baby’s eyes.
But there are some probabilities you can take into consideration. Brown and green are dominant eye colors, while blue is a recessive eye color. So, if both parents have brown eyes, the baby will most likely have brown eyes as well. However, if one of the grandparents has blue eyes, there is a probability that the baby ends up having blue eyes, despite the parents’ eye colors.
Finally, nobody, not even the doctor, can predict with certainty what color a baby’s eyes will be. It's all up to genetics and nothing more. So, enjoy that first wonderful year with your little one as you discover all the small changes in his dazzling eyes.