There are two common myths about babies' eyes. One: that they're born with their
eyes already fully grown. And two: that all babies are born with blue eyes that
change color over time. Neither of these is true but like many enduring myths
it's easy to see where the misunderstanding comes from.
Babies' eyes do grow after they're born. There are usually two growth periods.
One in the first few years of life and the second during puberty. But the eyes don't
grow as much, in proportion, as other parts of the body. At birth, a baby may
only be one-quarter of its adult height. But the eyes at birth are often already
more than two thirds of their adult size. This makes the eyes appear larger
compared to the rest of the body and makes their growth much less noticeable.
As for babies being born with blue eyes that change color -- that is common but
it's a myth that all babies are born with blue eyes. Some babies are born with
darker eyes. Those babies with blue eyes typically have less melanin skin pigment.
Melanin continues to develop after birth and it can turn the blue eyes brown or hazel.
Often this change happens in the first year, but it can continue for a few
more years in some children.