When Do Babies' Eyes Change Color?

Heard your cutie's peepers may go from blue to brown? Find out why and when your baby's eyes will change color, and how genetics influence baby's physical development.

6 Fun Facts About Baby's Eye Color

In addition to questions about when baby will sit up, crawl, and walk, many parents ask their doctor about the baby's eye color. Will his light eyes stay that way? Will he end up with his dad's baby blues? Or will he take after Mom, the brown-eyed girl? Why does your child have darker eyes than his siblings? And why does a baby's eye color change anyway? Here's what you need to know about why and when your baby's true eye color will make its entrance.

beautiful baby BananaStock/ Jupiter
Why Does Eye Color Change?

When babies are born, especially fair-skinned ones, they have light-colored eyes because they have very little melanin in their eyes. Melanin is a type of pigment that gives color to the eyes, skin, and hair. "The amount of melanin in the iris, the colored part of the eye, determines what color a person's eyes will be," says Douglas Fredrick, M.D., a pediatric ophthalmologist at Stanford Children's Health in Palo Alto, California. Genetics control how much melanin (or pigment) a person will have in her body. The DNA your baby receives from you and your partner determines if her eyes will be blue, brown, green, or another color. She may be born with blue eyes (the eyes sometimes don't produce much -- if any -- melanin while the baby is in the womb), but after birth, light stimulates the production of melanin, which is why the eye color may darken or change over time. It's important to understand that it's not the color of the pigment that causes the change. There is no blue, gray, green, or hazel pigment in the eye, Dr. Fredrick says. The only pigment we have in the eye is brown, and it's the amount of that pigment that determines whether a person's eyes will be light or dark, he explains.

Science aside, it may seem like a simple equation: One brown-eyed parent plus one brown-eyed parent should equal one brown-eyed baby, right? Not necessarily. There are multiple genes in the body that contribute to eye color, Dr. Fredrick says. Even if a baby's parents both have brown eyes, it's possible for the baby to end up with blue ones if the parents have the genes for blue eyes somewhere in their genetic makeup. How can a parent with one eye color have genes for a different eye color? Through their grandparents, of course. A baby's eye color depends not only on the eye color of Mom and Dad, but of the grandparents too, says Jean Moorjani, M.D., a pediatrician at Arnold Palmer Hospital for Children in Orlando. So if you and your partner both have brown eyes and your little girl has green, Grandpa or Grandma may be the reason.

Even if you've seen eye color charts or calculators, don't think any predictions are set in stone. "Nobody, the doctor included, can predict what color the eyes will be once the baby gets older," Dr. Fredrick says. And what your baby eats or does, and how much or how little you expose her to light, doesn't matter either. It's all up to genetics and nothing more. But if your baby was born with brown eyes, it means she already has the amount of melanin assigned by her genetic code, which means her eye color won't change.

When Does Eye Color Change?

Typically, you'll see the biggest change in the first 6 to 9 months of life, Dr. Moorjani says. Over several weeks or months, you may notice your baby's eyes getting darker. The change is so gradual that you may not notice until, one day, the baby wakes up and surprises you with a different eye color! By 12 months, most babies will have their permanent eye color, although Dr. Fredrick says that some children's eye color may still change up until age 6, though this occurrence is rare and the change won't happen overnight.

Red Flags and Other Concerns

Generally, your baby's color will change without affecting his vision or any other eye issues. But if only one eye changes color (which is very rare) or if you notice cloudiness in your baby's eye, contact the pediatrician or pediatric ophthalmologist.

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