Squint in Babies: What Is Normal, and When to Have Their Eyes Checked

In the family photo, one of your two-month-old's eyes drifts towards the nose. The next day, nothing. Should you worry? A squint in a baby of a few weeks is very often passing. But beyond a certain age, that same wandering gaze becomes a sign to take seriously, because a child's sight is built during the first years of life and a neglected eye can lose its abilities.

Here is how to tell what is normal from what is not, at what age to have the eyes checked, and what amblyopia, glasses and the eye patch involve.

Is it normal for a baby to squint?

Yes, in the first weeks, when it comes and goes. At birth, the eye muscles and the brain have not yet learned to coordinate the two eyes. The UK's NHS states that an intermittent squint is common before 3 months and generally not a problem.

Eye tracking, meaning the ability to follow an object with both eyes, settles in around 4 months, La Revue du Praticien reminds us. To encourage it, nothing beats your face, face-to-face games and a few high-contrast stimulation toys; you will find more ideas in our play and stimulation activities from 0 to 12 months.

To check whether the eyes are well aligned, the doctor has a simple test: they shine a light into the baby's eyes and look at the small reflection of the light, which should sit in the same place in both pupils, explain the Merck Manuals. That is why an impression of squint, even on a simple photo, deserves to be mentioned rather than settled at home.

When does a squint become a warning sign?

As soon as it is constant, at any age, or persists after 4 months, even if it only shows up at times. La Revue du Praticien considers any squint, constant or intermittent, abnormal after 4 months. The NHS, for its part, advises seeing a doctor if the squint is constant, or continues after 3 months.

Other signs should lead to an eye examination:

• a white reflection in the pupil, instead of the usual black or red one, sometimes noticed in a photo;
• a cloudy cornea, or an abnormally large eye;
• rapid, involuntary eye movements (nystagmus), a gaze that wanders or is fixed upwards;
• a red eye, or one that waters all the time;
• a child who tilts or turns their head to look, or who closes one eye;
• later on, a child who bumps into things, squints or gets very close to pictures.

The white reflection deserves a special mention. La Revue du Praticien classes it as a medical and surgical emergency: it can reveal a congenital cataract or a retinoblastoma, a rare eye cancer in young children. The NHS also recommends having any squint in a child seen by a doctor, notably to rule out that disease.

What is amblyopia, or "lazy eye"?

It is reduced vision in one eye, because the brain has learned to ignore it. When the two eyes do not look in the same direction, the brain receives two different images. To avoid double vision, it "switches off" the image from the eye that turns. Over time, that eye does not develop normal vision.

According to the MSD Manuals, amblyopia affects about 2 to 3% of children and usually sets in before age 2. A squint is not the only cause: a big difference in prescription between the two eyes, or an obstacle such as a cataract, can also bring it on.

What matters here is time. Vision is built mostly during the first three years and this development is complete around age 8; beyond that age, note the Merck Manuals, treatment hardly works any more. Without treatment, nearly half of the children who squint lose some vision in the affected eye. The earlier amblyopia is treated, the greater the chances of full recovery. La Revue du Praticien thus judges that screening at age 6 comes too late for optimal treatment.

How are squint and amblyopia treated?

Treatment follows a logical order, described by the MSD Manuals and the NHS:

1. Correct the eyesight with glasses, when a problem such as long-sightedness is involved. In some children, glasses are enough to straighten the eye.
2. Make the weak eye work, by covering the good eye for a few hours a day with a patch (occlusion) or, sometimes, by blurring its vision with a prescribed eye drop.
3. Operate on the eye muscles, if the squint persists despite glasses, once the vision of both eyes has been rebalanced. According to the Merck Manuals, the operation succeeds in more than 80% of cases, and about one child in five needs a second procedure.

The NHS also mentions eye exercises and, in some cases, injections into the muscles, whose effect is temporary. The choice is up to the eye specialist.

When should you have your child's eyesight checked?

In France, the health record book schedules an eye examination before day 8, then at 2, 4 and 9 months, amblyopia screening around age 2, an examination around age 3-4 and check-ups afterwards throughout school, according to La Revue du Praticien. The MSD Manuals add that a child of 3 or 4 who cannot manage a vision test with pictures or letters should see a specialist.

In Morocco, to our knowledge, there is no public schedule as detailed for the eyes. The simplest approach is to ask the paediatrician to check vision at every follow-up visit, and to write the examinations in the health record book. What the paediatrician does, and what falls to the eye specialist, is explained in our article on choosing a paediatrician.

For milestones in how your baby's gaze develops month by month, see also your baby at 3 months.

Screens and eyesight: what should you know?

Screens are not described as a cause of infant squint. They mainly raise the question of short-sightedness, which is rising among European children according to La Revue du Praticien. Its advice matches that of paediatricians: before age 3, avoid rooms where the television is on; at any age, no screen in the bedroom, not to calm the child, not during meals, not before sleep. All the guidelines are in our article on screens and young children.