Is It True That All Babies Are Born with Blue Eyes?

There are a lot of myths out there about predicting the physical characteristics of your unborn baby, from sex to height to hair color. And while most of the myths can easily be debunked with science, eye color remains a bit mysterious. It turns out that predicting a baby's eye color is a little more complicated than determining which parent has a blue eye gene and which has brown.

To make matters even more fascinating, some babies are born with an eye color that is temporary and slowly changes over the course of several months, which may be where the myth that all babies are born with blue eyes comes from.

We talked to the experts to find out how eyes get their color and why some babies are born with blue eyes that change to a different color over time.

What Is Eye Color?

Eye color refers to the color of one's iris. It is a physical trait determined by several factors, including genetics. Shades can vary on a spectrum. Eyes can be light blue, for example, or lapis or aqua. And the most common eye color is brown.

"Eye color is the pigment within the eye's iris, which lies below the cornea. This pigment, or melanin, is produced by melanocytes, cells that are also responsible for the color of a person's skin and hair," says Leah Alexander, M.D., FAAP, a board-certified pediatrician in New Jersey and medical consultant for Moms Love Best.

But interestingly, the iris has five layers, and it's only the top layer that gives us the color of our eyes, explains Bobby Saenz, O.D., MS, FAAO, clinic director LASIK San Antonio and Professor at Rosenberg School of Optometry. "This layer is called the anterior border layer. In the anterior border layer, we have melanin, which is where we get eye color from."

There are six categories of eye color, and each of them can range from light to dark. These include:

• Amber
• Blue
• Green
• Hazel
• Grey
• Brown

People with irises that have little to no melanin can appear to have red, pink, or violet eyes. This is a condition known as albinism.

How Is Eye Color Determined?

According to the American Academy of Ophthalmology (AAO), your eye color is as unique as your fingerprint—and it doesn't necessarily come from your parents. The AAO explains that although a baby gets its genetic makeup from two parents, that doesn't mean it is easy to predict eye color. Scientists have long studied brown, blue, and green to understand how these common eye colors get passed through a family tree, but there is little to explain how a baby could get blue eyes when the parents each have brown. And that might be because it has less to do with what eye color a parent has than how much pigmentation they are passing on.

"Eye color is determined by the overall amount of melanin that the melanocytes produce throughout the body," says Dr. Alexander. "For example, people who have darker skin typically have brown or darker eye colors. It is also based on the amount of brown pigment within the iris. Lighter eye colors such as blue, green, or hazel have some brown pigment, just less. Eye color is also affected by how light reflects off of melanin within the iris. This is the case in individuals with green eyes. Because there are many variations in the amount of melanin, each person's eye color is unique."

Here's another fun twist in the science of eye color: "Blue eyes and brown eyes both have the same colored melanin," says Dr. Saenz.

What Color Eyes Are Babies Born With?

If eye color is dependent on how much melanin is in the iris, why does it seem like most babies have blue eyes when they're born and then change a few weeks or months later?

"We have to get a little technical to answer this question," says Dr. Saenz. "The cells that determine eye color come from the neural crest cells and migrate into the iris late in gestation and postnatally, so that means our eye color cells take about six to nine months to get where they are traveling to. This migration process is thought to be controlled by the sympathetic nervous system."

Researchers discovered this incredible migration process in 1993 when they used an electron microscope to study the eyes of a patient with Horner's syndrome, which changed the patient's eye color from brown to blue.

This slow change in eye color is likely where the myth that all babies are born with blue comes from—the truth is that babies are born with their lifelong eye color, but in some babies, it may take a few months for that color to show fully.

When Does Baby's Eye Color Change—If It Changes at All?

Only around 10 to 20% of babies' eye color changes. If your baby was born with blue eyes, but you and your partner have brown eyes, you might be wondering what kinds of tricks nature is up to. But don't worry; in all likelihood, your baby's eyes will slowly change into their lifelong color within six months.

"All three of my kids were born with blue-ish eyes. Everyone would ask, 'Where are the blue eyes coming from? Who has blue eyes in your family?'" Dr. Saenz shares. "I would just say, 'Oh, we will see how they turn out.' But deep down, I knew the sympathetic nervous systemic was going to kick in, and their eyes would turn brown. All three of my kids are over nine months old and all of them have brown-ish eyes."

Is There Any Way to Predict What Color Your Baby's Eyes Will Be?

It can be fun to try and predict your baby's physical characteristics, like hair and eye color, but those predictions might not hold much weight.

"In the past, genetic assessments were performed. Attempts were made to predict the eye color of future children based on that of the parents and grandparents," says Dr. Alexander. "However, recent research has shown that this strategy does not account for the roles of ethnicity, variations in the amount of melanin, and other hereditary factors. In addition, eye color can change during the first three years of life. Therefore, predicting eye color can be challenging."

Still, many of us remember playing with Punnet squares in 7th-grade biology to try and crack the code of family genetics. "There is a good chance in 7th grade, when you were first learning about genetics, especially Mendelian genetics, you learned brown eyes are dominant and blue eyes are recessive. The simple model works most of the time," says Dr. Saenz. "If both parents have brown eyes, there is a zero to 25% chance their kids will have blue eyes. For most of us, though, it's 0%. If both parents have blue eyes, then it's almost a 100% chance that their kids will have blue eyes. Now if one parent has blue eyes and the other has brown eyes, then there is a zero to 50% chance of the child having blue eyes."

The Bottom Line

Dreaming about what your baby's eye color will be is super fun, even if it is hard to predict. And while science is still learning about the cool intricacies of how eye color works, what we do know is that your baby's eye color will depend on factors such as genetics and how much melanin they've inherited. We also know that up to 20% of babies will experience their eyes changing color in their first six months of life.

"If a baby is born with an unusual eye color, this warrants an evaluation by an ophthalmologist," says Dr. Alexander. "For example, pink eyes signify albinism and may coexist with fair skin and hair. Cloudiness of the iris could indicate the presence of a cataract which could impair the development of normal vision. In addition, if only one eye changes its color over time or seems to lose color, this could be a sign of a condition that could result in vision loss."

Talk to your health care provider if you have questions or concerns about your baby's eye and vision health.