Short-sightedness

My preschooler is already short-sighted: why so early, and what to check

The screening letter says minus, and she is only four. Why short-sightedness this young is unusual, what the eye doctor checks first, why an early start matters, and what the plan usually looks like.

by Dr Chan Li Yen · MBBS, MOphth (UM), Fellowship in Paediatric Ophthalmology & Strabismus

Dr Chan Li Yen, consultant paediatric ophthalmologist, MMC 43128, NSR 132980 · Eagle Eye Centre Kuala Lumpur, Petaling Jaya

12 min read · 2,188 words

Key takeaways

Short-sightedness is uncommon before school age. A 2026 review of 14 Malaysian studies found it in 2.54% of children aged 0 to 6, against 26.48% at 7 to 12.
Ask for the number to be measured with drops that relax the focusing muscle. A reading without drops can be partly focusing effort, and the drops settle which it is.
Starting young matters because the eye has more years to grow. In a Singapore study of 928 children, each year earlier that short-sightedness began raised the odds of high myopia at age 11 by 2.86 times. That shows a direction, not a forecast for one child.
Very high numbers in a young child are rare, under 1% in preschoolers, and are more often linked to prematurity, development or a body-wide condition, so the doctor looks at the whole eye and the whole child.
The usual plan is glasses if needed, daily time outdoors and regular rechecks. Evidence for myopia control under age 6 is thin, and it is a case-by-case talk with the eye doctor.

Your four-year-old squints at the television, or a kindergarten screening letter says to see an eye doctor, and the number that comes back has a minus sign in front of it. Almost every parent asks the same thing: how can she be short-sighted already?

This page is about that child. It sets out why short-sightedness (rabun jauh) this young is unusual, what I check first, why an early start matters, and what the plan usually looks like. Nothing here is a forecast for one child, and none of it is anyone's fault.

Why is my 4 or 5 year old short-sighted when most children are not until school age?

Because it is uncommon at this age, and the usual cause is the same as in older children: the eyeball has grown a little longer than it should. A 2026 review of 14 Malaysian studies found short-sightedness in 2.54% of children aged 0 to 6, against 26.48% at 7 to 12 and 42.71% at 13 to 18. The International Myopia Institute (IMI) describes the common pattern as starting after age 5 or 6.

So a preschooler with a minus number sits outside the usual pattern, and that is why she deserves a careful look rather than a quick pair of glasses. A short-sighted parent raises the odds, and both parents short-sighted: what it means for our child sets out the studies. Some early cases have another cause, which is why the next two sections matter. The action: bring the family's glasses history.

Is it really short-sightedness, or did the machine over-read?

Sometimes part of the number is the focusing muscle working too hard, and only a measurement with drops that relax it tells the two apart. The American Association for Pediatric Ophthalmology and Strabismus (AAPOS) says children need stronger drops than adults to measure their need for glasses, and that one kind of drop relaxes the eye's ability to focus.

That is why a reading from a school chart, a shop machine or a quick clinic test is a reason to look further, not a final answer. Pseudomyopia, when short-sightedness is a focusing spasm explains how a first number can shrink once the muscle is relaxed. The drops widen the pupil and blur near vision for a while: AAPOS says this usually lasts 4 to 24 hours, and children's eyes tend to stay wide longer. About those eye drops at the clinic covers the day. The action: if the first reading was taken without drops, have it repeated with drops before anything is decided.

Why does it matter that it started so young?

Because the eye has more years of growing ahead, and in studies children who became short-sighted younger tended to reach higher numbers. In Singapore, Chua and colleagues followed 928 short-sighted children, first seen at 7 to 9, until age 11. For each year younger the short-sightedness began, the odds of high myopia (minus 5.0 dioptres or worse) at 11 were 2.86 times higher. Age of onset alone predicted high myopia with a score of 0.85 (1.0 is perfect, 0.5 a coin toss).

Those children were already at primary school, so the figure shows a direction and not a forecast for a four-year-old. AAPOS puts it in one line: children who get short-sightedness early in life tend to need stronger prescriptions later. The IMI also cites a study of short-sighted preschoolers in China in which those with mild numbers, minus 0.5 to minus 2.0 dioptres, changed by 0.85 dioptres a year on average. That is a group average, and your child may not follow it.

What they do say is that a small number in a small child is not one to leave alone. Early does not mean high, and no study can say where one child will end up; at what age does short-sightedness stop getting worse covers the long road, and how fast is too fast covers the yearly change. The action: keep the date and the number from this first visit, so the next measurement has something to be compared with.

What else will the doctor check in a child this young?

Whether the eye is healthy and whether anything else explains the number. For a highly short-sighted young child, the IMI lists measurement with drops, sight in each eye, colour vision, eye movements, the length and curve of the eye, and a look at the back of the eye, along with questions about family, hearing, joints and general health.

The reason is in the figures. High myopia, minus 6.0 dioptres or worse, is rare in preschool children, under 1% in the IMI's 2023 report, and in them a cause is found far more often than in older children. A 2001 hospital survey found that 54% of highly short-sighted children under 10 were born premature, had developmental delay or had an underlying body-wide condition such as Marfan, Stickler, Noonan or Down syndrome. A UK community study found that 44% of children under 10 with myopia worse than minus 5.0 dioptres had an eye condition (25%) or a previously unrecognised general condition (18%).

Please read that in proportion. Those figures are for high myopia, which is under 1% at this age. How far the checking goes depends on the number, the eye and the child's history. The IMI says premature babies are at high risk of short-sightedness and need monitoring; eye checks after the NICU and eye checks through childhood in Down syndrome and genetic conditions cover those families. The action: bring the health book, the birth history, and the name of anyone in the family with very strong glasses or a retinal problem.

What does the plan usually look like for a preschooler?

Glasses if the number is enough to affect how she sees, daily time outdoors, ordinary care with near work, and regular rechecks, with myopia control a separate conversation. The IMI notes that in preschool children it is common practice not to correct lower levels of short-sightedness. It quotes American Academy of Ophthalmology advice that glasses are merited for myopia worse than minus 2.5 dioptres at ages 3 to under 4, and says such thresholds rest on professional experience, not trial data.

For a 4 or 5 year old with a milder number, whether glasses are worn all day, for distance only or not yet is a judgement about how she sees, how the two eyes compare and how she copes. If glasses are prescribed, glasses a toddler will keep on helps with the first weeks. Glasses do not push the number up: the IMI describes full correction in school-age children as aimed at clear distance sight and avoiding faster change.

Outdoor time has the best-studied evidence, with limits. A 2024 Cochrane review of 5 trials and 10,733 primary school children, mostly aged 6 to 9, found less change in refraction after 2 years in the outdoor groups, by 0.13 dioptres (moderate-certainty evidence), where the review had set 0.1 as a meaningful difference. A small gain, in older children; two hours outside: the cheapest myopia habit sizes it honestly. For screens, the studies are less clear than the advice: see what the studies show about screens.

AAPOS says most children with short-sightedness should have yearly eye examinations. A preschooler whose number is moving may be asked back sooner. The action: ask for the next visit date before you leave.

Can a child this young have myopia control, and does it work?

It can be discussed, but the evidence under age 6 is thin. The IMI notes that treatments to slow short-sightedness have generally been tested in children aged 6 to 16, and for young children with high myopia it asks for a case-by-case approach because of the lack of evidence.

The labelled ages differ by treatment. The American Academy of Ophthalmology lists low-dose atropine drops for children aged 5 to 18, special spectacle lenses for 6 to 12 and peripheral defocus contact lenses for 8 to 12. The LAMP trial in Hong Kong did enrol children aged 4 to 12 with short-sightedness of at least minus 1.0 dioptre, and its 0.05% drops slowed the change over a year. Its abstract gives no result for the youngest children alone, so there is no figure for a 4 year old that I can quote you.

For a child born early, the IMI says short-sightedness is not mainly a matter of a long eye, and evidence that the eye is lengthening should come before any slowing treatment. Cost, side effects and stopping are in atropine drops for myopia: what the numbers say, slowing myopia down and the guide to myopia control in Malaysia and ten questions to ask before you pay. Nothing sold as a cure is real; see eye drops that cure short-sightedness. The action: if control is offered to a preschooler, ask what evidence exists for her age, and what measurements will show whether it is working.

Book the eye examination now, not at the next routine slot, if your child…

Has a short-sighted reading from a school screening or a shop but has not had an examination with drops.
Has an eye that turns in or out, or seems to see less with one eye.
Was born early, or has hearing, joint or developmental concerns, and has not had a full eye examination since the minus number was found.
Cannot see the board or the television clearly even with the glasses.
Suddenly sees flashes of light, a shower of new floaters or a shadow across the sight: go the same day.

Common questions

Is it unusual for a 4 or 5 year old to be short-sighted?

Yes. A 2026 review of 14 Malaysian studies found short-sightedness in 2.54% of children aged 0 to 6, against 26.48% at 7 to 12 and 42.71% at 13 to 18. The International Myopia Institute describes the common pattern as starting after age 5 or 6, so a preschooler deserves a careful examination.

Will my child end up with high myopia because it started so early?

Not necessarily. In a Singapore study of 928 children followed from age 7 to 9 up to 11, each year younger at onset raised the odds of high myopia at 11 by 2.86 times. That describes a group, and those children were older than yours. Early onset is a reason for close follow-up, and no study can say where one child will end up.

Why does my preschooler need eye drops for the measurement?

Because the drops show the true power. AAPOS says children need stronger drops than adults to measure their need for glasses, and that one kind relaxes the eye's ability to focus. Without them, a child's focusing effort can make the eye read as more short-sighted than it is.

What else could explain short-sightedness at this age?

Rarely, another condition. The IMI's 2023 report says high myopia of minus 6.0 dioptres or worse is under 1% in preschool children. A 2001 hospital survey found 54% of highly short-sighted children under 10 were born premature, had developmental delay or had an underlying systemic disorder. Those figures are for high myopia, and the doctor decides how far to check for a lower number.

Does my child need glasses right away?

It depends on the number and on how she sees. The IMI notes that in preschool children it is common practice not to correct lower levels of short-sightedness. It quotes American Academy of Ophthalmology advice that glasses are merited for myopia worse than minus 2.5 dioptres at ages 3 to under 4, resting on experience and not trial data. The doctor decides for your child.

Can we start atropine drops now to slow it?

That is a decision for the eye doctor, and the evidence for a child this young is thin. The IMI says treatments have generally been tested in children aged 6 to 16. The American Academy of Ophthalmology lists low-dose atropine for ages 5 to 18. The LAMP trial enrolled children aged 4 to 12, but its abstract gives no result for the youngest alone.

Does time outdoors help a child who is already short-sighted?

A little. A 2024 Cochrane review of 5 trials in 10,733 primary school children, mostly aged 6 to 9, found less change in refraction after 2 years with more outdoor time, by 0.13 dioptres. It is a small gain, measured in older children, and it is free and good for any child.

How often will my child need to be seen?

AAPOS says most children with short-sightedness should have yearly eye examinations. A preschooler whose number is changing may be asked back sooner. Ask for the next visit date before you leave, and keep each number so the doctor can compare.

References

Malaysian Journal of Medical Sciences · Prevalence of Myopia in Children and Adolescents: A Systematic Review of Malaysian Prevalence Studies (Tan et al., 2026) · pubmed.ncbi.nlm.nih.gov
Ophthalmic and Physiological Optics · Age of onset of myopia predicts risk of high myopia in later childhood in myopic Singapore children (Chua et al., 2016) · pubmed.ncbi.nlm.nih.gov
Investigative Ophthalmology & Visual Science · IMI Management and Investigation of High Myopia in Infants and Young Children (Flitcroft et al., 2023) · pmc.ncbi.nlm.nih.gov
AAPOS · Dilating eye drops · aapos.org
AAPOS · Myopia and treatment of myopia in children · aapos.org
American Academy of Ophthalmology · Myopia control in children · www.aao.org
Cochrane Database of Systematic Reviews · Interventions to increase time spent outdoors for preventing incidence and progression of myopia in children (Kido et al., 2024) · pubmed.ncbi.nlm.nih.gov
Ophthalmology · Low-Concentration Atropine for Myopia Progression (LAMP) Study (Yam et al., 2019) · pubmed.ncbi.nlm.nih.gov

By Dr Chan Li Yen. General information only. It does not replace a consultation. If you are worried about your child's eyes or vision, please see an eye doctor.