Infant Eye Development


Newborn babies and their eyes

Soon after your baby is born, your doctor will examine their eyes to rule out signs of congenital cataracts or other serious neonatal eye problems. It is very rare for there to be any problem with a newborn’s vision. However, they must be detected and treated early to minimise their impact on your child’s vision development.

Babies’ eyes appear to be very large because normal infant development proceeds from the head down and newborn babies’ eyes are already about 70% of their adult size. They will continue to grow and develop for the first two years of life.

New babies and light

Your new baby’s eyes are not very sensitive to light in the first month. A one-month-old cannot detect light as easily as adults do – they need 50 times more light to see that light is present. So your new baby’s sleep will not be disturbed if you leave some light on in the room where they sleep.

Focus takes time

In the first week of life, babies don’t see in sharp focus and only in shades of gray. This is because nerve cells in their retina and brain that control vision are not fully developed. Also, a newborn infant’s eyes don’t have the ability to focus on near objects. So you needn’t worry if your baby doesn’t seem to be focusing on objects, including your face. It just takes time.

Colours

Infants start to develop the ability to see in colour very quickly. At one week after birth, they can see red, orange, yellow and green. But it takes a little longer for them to be able to see blue and violet. This is because blue light has shorter wavelengths, and fewer color receptors exist in the human retina for blue light.

Babies prefer mother’s face

Even with this limited vision, within a few days after birth babies prefer looking at an image of their mother’s face to that of a stranger. Researchers believe this preference depends on large, high-contrast stimuli, like the boundary of the mother’s hairline to her face. Studies showed that if these boundaries were masked with a scarf or bathing cap, the infants’ preference of looking at their mother’s face went away.

Eyes take time to work together

Don’t be too concerned if your baby’s eyes sometimes don’t appear to be working together as a team early on. One eye may occasionally drift inward or outward from proper alignment. This is normal. But if you see a large and constant misalignment of their eyes, tell your GP or eye care practitioner right away.

Baby’s eyesight milestones

It takes several months for your baby’s vision to develop fully. By the time a baby is two-three months old their eyesight has significantly advanced. Their focus has improved and their eyes start to work together better. By the time your baby is three months old they should be following moving objects and starting to reach for things they see.

At three months

By three months old babies are learning how to move their gaze from one object to another without having to move their head. At this age their eyes are becoming more sensitive to light and you may want to dim the lights a bit more for naps and bedtime.

At four-six months old

During these months, babies’ vision advances so that they can see more clearly and move their eyes more quickly and accurately to follow moving objects.

At this stage, babies’ eye-hand coordination improves so they can quickly find and pick up objects and accurately things to their mouth.

At six months

By the time your baby is six months old their vision should have improved from about 20/400 at birth to approximately 20/25. They can now see colours as well as an adult.

Six months old is a good time for your baby to have their first eye examination. Even though your baby doesn’t know the letters on a wall chart, your eye doctor can still:

  • Test their sight
  • Detect nearsightedness
  • Detect farsightedness and astigmatism
  • See how well a baby’s eyes work together.

If you have your baby’s eyes examined at six months old, the practitioner will also check the health of your baby’s eyes and look for anything that might interfere with normal and continuing vision development.

From seven-12 months old

Your child is probably starting to crawl and is better at judging distances and more accurate at grasping and throwing objects. This is an important developmental time for your child. They are developing more awareness of their overall body and learning how to coordinate their vision with their body movements.

It is perfectly normal for your baby’s eyes to change colour during these months. Most babies are born with blue eyes because darker pigments in the iris aren’t completely developed at birth. Over time, more dark pigment is produced in the iris, which will often change your child’s eye color from blue to brown, green, gray or a mixture of colours.

Eye alignment problems or ‘squint’

Be sure to pay close attention to how well your baby’s eyes work together as a team. ‘Strabismus’ is the term for a misalignment of the eyes or a ‘squint’. It is important that it is detected and treated early so the vision in both eyes develops properly. Left untreated, strabismus can lead to amblyopia or ‘lazy eye’. Most babies with strabismus can be treated with glasses if the condition is diagnosed early, whereas more complicated treatment may be required if your child is not diagnosed until they are older.

So, although it takes a few months for an infant’s eyes to work properly together, if you feel one of your baby’s eyes is misaligned constantly or does not move in synch with the other eye, contact your pediatrician or eye doctor as soon as possible.

Vision problems of premature babies

The average length of a normal pregnancy is 40 weeks (280 days). Babies born before 37 weeks of gestation are at greater risk of eye problems than full-term babies, and the earlier the baby is born the greater the risk.

Retinopathy of prematurity (ROP)

Premature babies are at risk of developing ROP. This is when the normal tissue in the retina is replaced with fibrous tissue and blood vessels. ROP can cause:

  • Scarring of the retina
  • Poor vision
  • Retinal detachment.

In severe cases, ROP can cause blindness.

All premature babies are at risk of ROP. If the baby is very small, they are more at risk especially if they need to be in a high-oxygen environment immediately after birth.

If your baby is born prematurely, your obstetrician will usually refer you to a pediatric ophthalmologist so they can do an internal eye exam to rule out ROP.

Nystagmus

This is when both your babies eyes involuntarily move back and forth. In most cases, nystagmus causes the eyes to drift slowly in one direction and then ‘jump’ back in the other direction. The eyes usually move from side to side, but they can move diagonally or around in a circle too.

Babies can be born with nystagmus, or it can develop weeks or months later. Babies at risk are those whose optic nerve has not completely developed, or who have albinism (babies born without enough pigment to protect their skin and eyes) and congenital cataracts. The bigger the eye movements are, the more likely the baby’s vision and visual development will be affected.

If your baby shows signs of nystagmus, your GP will refer you to a paediatric ophthalmologist or other eye doctor immediately.