Retinopathy of Prematurity (ROP)

Introduction

If your baby was born early or with a low birth weight, you may have heard the term retinopathy of prematurity, or ROP, from the neonatal team. It can be frightening to learn that your baby’s eyes need to be checked or treated, especially while you are still adjusting to life in the neonatal intensive care unit (NICU) or settling in at home with a small, fragile newborn.

This article is written for parents and families who are navigating ROP — whether your baby is being screened for the first time, has been diagnosed with a particular stage of ROP, has just had treatment, or is now in long-term follow-up. The aim is to explain what ROP is, why it happens, how it is found and treated, and what the journey ahead may look like for your child’s vision.

ROP is one of the most studied conditions in neonatal ophthalmology, and outcomes have improved substantially in recent decades. With careful screening and timely treatment when needed, most babies with ROP do not lose vision. Understanding the condition can help you ask informed questions and feel like an active partner in your baby’s care.

What Is Retinopathy of Prematurity?

In a full-term baby, these retinal blood vessels finish growing just before birth. In a baby born prematurely, vessel growth is incomplete. After birth, in the very different environment outside the womb, these vessels may grow abnormally instead of completing their normal pattern. The medical name for this abnormal vessel growth in premature babies is retinopathy of prematurity, or ROP.

In mild ROP, the abnormal vessels eventually mature on their own and the retina develops normally. In more severe ROP, the abnormal vessels can pull on the retina, cause bleeding, or in the worst cases, lead to retinal detachment — where the retina separates from the back of the eye. Retinal detachment in an infant can cause permanent vision loss if not treated.

ROP is described using a standard system called the International Classification of Retinopathy of Prematurity (ICROP), now in its third edition (ICROP3). This system lets eye doctors around the world describe what they see in the same language. The next sections explain that system in parent-friendly terms.

Why ROP Happens: Causes and Risk Factors

The main cause of ROP is prematurity itself. The earlier and smaller a baby is at birth, the higher the risk. Two factors carry the most weight:

• Gestational age at birth — how many weeks of pregnancy were completed. Babies born before 32 weeks are at greatest risk, and risk is highest in babies born before 28 weeks.
• Birth weight — babies weighing less than about 1500 grams (1.5 kg) at birth are at higher risk, with the risk rising as birth weight falls.

Beyond prematurity, several factors during the early newborn period can influence the risk and severity of ROP:

• Oxygen exposure. Premature babies often need extra oxygen to support their lungs. Both too much and too little oxygen can affect retinal vessel development. NICU teams monitor oxygen levels carefully to balance the needs of the lungs, brain, and eyes.
• Infections (sepsis) in the newborn period.
• Slow weight gain in the first weeks of life.
• Other illnesses of prematurity such as breathing problems requiring ventilation, intraventricular haemorrhage (bleeding in the brain), or necrotising enterocolitis (a serious bowel problem).
• Blood transfusions in some studies.

It is important to understand that ROP is not caused by anything a parent did or did not do. It is a consequence of being born too early, before the eyes had finished developing. In countries including India, ROP is recognised as an important cause of avoidable childhood blindness, and the focus of public health programmes is on making sure every at-risk baby is screened and treated in time.

A pattern noted by clinicians and the World Health Organization is that in many middle-income settings, including parts of India, ROP can also occur in slightly larger and more mature babies than is typical in high-income countries. This is one reason that local screening criteria in India are often broader than the criteria used in some Western countries.

Screening for ROP

Because early ROP causes no outward signs — a baby’s eyes look normal from the outside — screening is the only way to find it. Screening is done by an ophthalmologist (eye doctor) with training in examining infant eyes.

Who Is Screened

Screening criteria are set by national guidelines and may differ slightly between countries. In India, screening is generally offered to:

• Babies born at or before 34 weeks of gestation, or
• Babies with a birth weight of 2000 grams or less, or
• Larger or more mature babies who had a stormy NICU course (prolonged oxygen, sepsis, multiple transfusions, etc.) at the discretion of the treating team.

Joint guidance from the American Academy of Pediatrics, the American Academy of Ophthalmology, and the American Association for Pediatric Ophthalmology and Strabismus uses similar but somewhat narrower criteria in high-income settings. Your neonatal team will follow the criteria that apply locally.

When the First Examination Happens

The first eye exam is usually done between 4 and 6 weeks after birth, or between 30 and 31 weeks of corrected age (gestational age plus weeks of life), whichever comes later. This timing is chosen because ROP rarely needs treatment before this point, but waiting longer risks missing important findings.

What the Exam Involves

Before the exam, dilating eye drops are placed to widen the pupils so the doctor can see the retina. The drops may be put in more than once. A tiny instrument called a lid speculum gently holds the eyelids open, and the doctor uses an indirect ophthalmoscope (a head-mounted light with a magnifying lens) to look at the back of each eye. Sometimes a small wire-like instrument is used to gently move the eye for a complete view.

The exam typically takes only a few minutes per eye but can be uncomfortable for the baby. Babies may cry, hold their breath, or have temporary changes in heart rate or oxygen during the exam. The NICU team monitors the baby throughout. Sugar water (oral sucrose) and gentle swaddling are commonly used to comfort the baby. The discomfort is short-lived.

In some centres, a special wide-field camera (such as a RetCam) is used to take photographs of the retina. Telemedicine programmes — where images are taken locally and reviewed by an ROP expert elsewhere — have expanded screening reach, particularly in regions with few specialists.

How Often Screening Continues

One exam is rarely enough. Depending on what is found, the ophthalmologist will schedule the next exam in anywhere from a few days to a few weeks. Screening continues until:

• The retinal vessels are fully mature, or
• ROP has reached a stage where it is regressing safely on its own, or
• Treatment has been carried out and the result is stable.

It is essential that parents keep every scheduled appointment. ROP can progress rapidly, sometimes within a week, and a missed exam can mean a missed treatment window.

Stages and Zones: Understanding the Diagnosis

• Zone I is the innermost circle, around the centre of the retina. ROP in zone I is the most serious because it threatens central vision.
• Zone II is a middle ring extending further out.
• Zone III is the outermost crescent, furthest from the centre. ROP here is generally less worrying.

Stages

Stages describe how abnormal the vessel growth is at the boundary between vascularised and non-vascularised retina:

• Stage 1 — a thin line is visible between the developed and undeveloped retina.
• Stage 2 — the line has become a raised ridge.
• Stage 3 — abnormal blood vessels are growing from the ridge into the gel of the eye (the vitreous).
• Stage 4 — the retina is partially detached. Stage 4A spares the central vision area; stage 4B involves it.
• Stage 5 — the retina is completely detached.

Plus Disease

“Plus disease” describes abnormal widening and twisting of the blood vessels at the back of the eye. It is a sign that the disease is active and progressing. “Pre-plus” is a milder degree of the same change. The presence of plus disease often tips the balance towards treatment.

Aggressive ROP

A particularly rapid and severe form, previously called aggressive posterior ROP (AP-ROP) and now simply aggressive ROP (A-ROP) under ICROP3, can develop without progressing through the typical stages. It needs urgent treatment.

Putting It Together

Your child’s ophthalmologist will combine zone, stage, and the presence or absence of plus disease into a description for each eye and use this to decide whether to continue observation or move to treatment. Many cases of mild ROP — especially in zone III or stages 1 and 2 without plus disease — resolve on their own without any treatment.

When ROP Needs Treatment

Most babies who are screened do not need treatment. When ROP does need treatment, it is because the findings cross a threshold known to carry a high risk of progression to retinal detachment without intervention.

Treatment is generally considered in situations such as:

• Zone I ROP at any stage with plus disease
• Zone I, stage 3 ROP with or without plus disease
• Zone II, stage 2 or 3 ROP with plus disease
• Aggressive ROP

This framework comes from a landmark clinical trial known as the Early Treatment for ROP (ETROP) study and is reflected in current American Academy of Ophthalmology and AAP guidance. Treatment timing matters — once the criteria are met, intervention is typically planned within 48 to 72 hours.

The treating ophthalmologist will explain which findings apply to your baby and why a particular plan is being suggested. Asking questions is welcomed; the more you understand, the better partner you can be in care.

Treatments for ROP

There are three main categories of treatment: laser therapy, anti-VEGF injections, and surgery. The choice depends on the stage and zone of ROP, the baby’s overall condition, and the resources and expertise available.

Laser Photocoagulation

Laser treatment has been the standard treatment for advanced ROP for several decades and remains widely used. A focused laser beam is applied to the peripheral retina — the parts that have not yet developed normal blood vessels. By treating this undeveloped tissue, the laser reduces the signals that drive abnormal vessel growth, allowing the disease to regress.

Laser is usually done in the NICU or operating theatre under sedation or general anaesthesia, depending on the baby’s condition and the centre’s protocol. It typically takes 30 to 60 minutes per eye. The treated peripheral retina becomes permanently non-functional, but this area is responsible only for the very edge of vision — central vision used for seeing faces, reading, and detail is preserved.

After laser, the ROP usually regresses over several weeks. Follow-up exams continue to make sure the disease is settling and not recurring.

Anti-VEGF Injections

Vascular endothelial growth factor (VEGF) is a protein that drives abnormal blood vessel growth in ROP. Medications that block VEGF — called anti-VEGF drugs, including bevacizumab, ranibizumab, and aflibercept — can be injected into the eye to slow this process. The injection is given through the white part of the eye with a very fine needle, after numbing and sterilising the surface.

Anti-VEGF treatment has several advantages compared with laser in certain situations:

• It is quicker to administer.
• It does not destroy peripheral retina, which may matter for the very young eye.
• It can reach into zone I disease more easily than laser.

It also has considerations:

• ROP can recur after the medication wears off, sometimes weeks or months later. Babies treated with anti-VEGF therefore need longer follow-up than babies treated with laser.
• Because the medication enters the bloodstream in small amounts, questions remain about possible effects on developing tissues elsewhere in the body. Studies are ongoing.
• The choice of drug, dose, and follow-up schedule varies between centres.

Major societies including the American Academy of Ophthalmology recognise both laser and anti-VEGF as accepted options, with the choice tailored to each baby. In some situations — particularly aggressive ROP in zone I — anti-VEGF is often favoured. In others, laser remains the preferred approach. Your ophthalmologist will explain which option is being recommended for your baby and why.

Surgery for Retinal Detachment

If ROP progresses to retinal detachment (stage 4 or 5), surgery may be considered to try to reattach the retina. The two main procedures are:

• Scleral buckling — a small silicone band is placed around the outside of the eye to indent the wall of the eye inward, helping the retina settle back into place.
• Vitrectomy — the vitreous gel inside the eye is removed, along with scar tissue pulling on the retina, allowing the retina to reattach.

Surgery for stage 4 ROP can have reasonable outcomes, particularly when the central retina is still attached (stage 4A). Surgery for stage 5 (total detachment) is much more difficult, and even when the retina can be reattached anatomically, useful vision may not return. The goal in advanced cases may be to preserve some level of light perception or simply to prevent further complications such as eye shrinkage.

The decision to operate at this stage is complex and depends on the surgeon’s experience, the structure of the eye, and a careful discussion of realistic expectations with the family.

Preparing Your Baby for Treatment

If your baby needs ROP treatment, the medical team will guide you through the practical preparation. Common steps include:

• Pausing feeds for a set number of hours before sedation or anaesthesia, to keep the airway safe.
• Routine pre-treatment checks of breathing, heart rate, and oxygen.
• Dilating eye drops applied an hour or so before treatment.
• A discussion with the anaesthesia or neonatal team about how the baby’s breathing will be supported during the procedure.

You will be asked to sign a consent form. Take the time you need to ask questions: what is being done, what the alternatives are, what risks are involved, and what to expect afterwards. If anything is unclear, ask again.

After Treatment: Immediate Recovery

After laser or injection treatment, your baby will be monitored in the NICU or recovery area. Common short-term effects include:

• Mild redness or swelling of the eyelids for a day or two.
• A short period of sleepiness from sedation.
• Temporary changes in feeding, often returning to normal within a day.
• Eye drops, such as antibiotics or anti-inflammatories, may be prescribed for a short period.

For surgery, the recovery is longer and depends on the type of operation. The surgical team will give detailed instructions about positioning, eye drops, and follow-up.

Risks and Complications of Treatment

All medical treatments carry some risk. The risks of treating ROP are weighed against the risks of leaving severe ROP untreated, which include progression to retinal detachment and blindness.

Possible risks of laser treatment include:

• Loss of some peripheral (side) vision, which is usually subtle and not noticeable to the child.
• A higher chance of being short-sighted (myopic) later in life.
• Rarely, bleeding inside the eye, cataract, or changes to the iris.
• Risks associated with sedation or general anaesthesia.

Possible risks of anti-VEGF injection include:

• Infection inside the eye (endophthalmitis), which is rare but serious.
• Late recurrence of ROP, requiring re-treatment.
• Potential systemic effects, still being studied.

Possible risks of retinal detachment surgery include:

• Incomplete reattachment of the retina.
• Bleeding, infection, or cataract.
• Need for further operations.

The team will discuss the specific risks that apply to your baby’s situation. Despite these risks, modern ROP treatment has dramatically reduced the rates of severe vision loss compared with the era before effective treatment existed.

What Happens If ROP Is Not Treated

Mild ROP — the majority of cases — resolves on its own without any treatment, and vision develops normally.

Severe ROP that meets treatment criteria but is not treated carries a high risk of progressing to retinal detachment and severe vision loss or blindness. In parts of the world without organised screening, ROP remains a leading cause of childhood blindness. The strong evidence behind screening programmes and the timely use of laser or anti-VEGF treatment is the reason these services have been expanded across India and many other countries.

Long-Term Follow-Up and Vision Outcomes

• Refractive errors — particularly short-sightedness (myopia), which is more common in children who had ROP, even if treatment was not needed. Glasses correct this.
• Strabismus — a misalignment of the eyes (squint), which may need glasses, patching, or surgery.
• Amblyopia — sometimes called “lazy eye,” where the brain favours one eye and vision in the other does not develop fully. Early detection and patching can improve outcomes.
• Cataract or glaucoma — less common but possible.
• Late retinal detachment — rare but can occur years later, particularly in eyes that had severe ROP.

A typical follow-up plan after ROP includes eye exams at intervals over the first few years of life, then periodic checks through childhood. The exact schedule depends on what stage of ROP your baby had and how it was treated. The ophthalmologist will lay out the plan, and it is important to attend every visit, even if your child seems to be seeing well.

Vision outcomes after ROP vary widely. Many children who had treated ROP grow up with good, functional vision — sometimes needing glasses, sometimes not. A smaller number have moderate visual impairment, and a small minority have severe vision loss, more often when ROP reached the most advanced stages or could not be treated in time. Your child’s ophthalmologist can give you the most realistic picture for your child as they grow.

Supporting Your Child’s Development

Vision is one of the most important senses for early learning. Even babies with normal eyes after prematurity benefit from supportive early development, and babies who had ROP — whether mild or severe — deserve particular attention to how their visual world is unfolding.

Practical points that families often find helpful:

• Attend all follow-up appointments — with the ophthalmologist, the paediatrician, and any developmental specialists.
• Watch for signs of vision concerns — not making eye contact by a few months of corrected age, not following objects, holding objects very close, persistent eye turning, or unusual head positions.
• If glasses are prescribed, make wearing them part of daily routine from the start. Children adapt quickly when glasses become normal.
• If amblyopia treatment is recommended, follow patching or eye-drop schedules carefully. The brain’s ability to learn to use a weaker eye is greatest in the first years of life.
• Consider early intervention services if your child has moderate or severe visual impairment. Vision specialists, occupational therapists, and early education programmes can help children with low vision develop other senses and skills.

Premature babies, with or without ROP, are at higher risk of certain developmental differences. Regular paediatric and developmental follow-up gives the best chance to identify and support any concerns early.

Living with the Diagnosis: Family Considerations

The NICU and the months after a premature birth are exhausting. Adding an ROP diagnosis to that experience can feel overwhelming. A few thoughts that families have shared:

• The information comes in waves. You will not absorb everything at the first conversation. Ask the team to repeat or write things down. Keep a small notebook for each appointment.
• One conversation at a time. Try to focus on the next decision rather than the entire future. ROP usually unfolds over weeks of NICU care, with multiple checkpoints.
• You are not the cause. ROP is a consequence of prematurity, not of anything a parent did. This is worth repeating to yourself, especially on hard days.
• Look after yourselves. Sleep, food, and the support of family or other parents of premature babies all matter. Parent support groups, including those organised through some NICUs, can be a source of practical wisdom.
• Build a relationship with the eye doctor. Long-term ROP follow-up often spans years. Finding a paediatric ophthalmologist with experience in premature babies, whose communication style works for your family, makes the journey easier.

Choosing Care for Your Baby

ROP care involves a team: neonatologists who manage the NICU course, ophthalmologists who screen and treat, and sometimes anaesthetists, retinal surgeons, and developmental specialists. When evaluating where your child will receive care, useful things to look for include:

• An ophthalmologist with training and ongoing experience in paediatric retinal disease and ROP screening.
• A NICU with an established ROP screening protocol that follows current national guidelines.
• Access to both laser and anti-VEGF treatment if needed.
• Access to retinal surgery in case advanced disease occurs.
• Clear arrangements for follow-up after NICU discharge, including reminders for appointments.
• Willingness to answer your questions in plain language.

Meeting the ophthalmologist before treatment, if circumstances allow, can help build trust. If a second opinion would help you feel confident in the plan, asking for one is reasonable; experienced teams welcome this.

Frequently Asked Questions

My baby’s eyes look completely normal. Could they still have ROP?

Yes. Early and even moderate ROP causes no outward change in how the eyes look. The pupil reacts to light normally, and the baby’s gaze can appear typical. ROP is only visible when the retina is examined directly with a special light and lens. This is why all premature babies who meet the screening criteria are checked, regardless of how their eyes look.

Is the screening eye exam painful for my baby?

The exam is uncomfortable rather than painful. The dilating drops sting briefly, and holding the eyelids open is unpleasant for the baby. Most babies cry during the exam and settle quickly afterwards. NICU teams use sugar water (oral sucrose), gentle wrapping, and pacifiers to comfort the baby. The benefit of finding treatable ROP greatly outweighs the brief distress of the exam.

If my baby’s ROP regresses without treatment, are the eyes completely safe?

Mostly, but follow-up still matters. Children who had any degree of ROP — even mild — have a somewhat higher chance of needing glasses, of developing strabismus, or of having amblyopia later in childhood. Regular eye check-ups during childhood help catch and treat these in time.

Will my child be able to see normally after laser or injection treatment?

Many children treated for ROP develop good, functional vision, sometimes with the help of glasses. Outcomes depend on the stage at which treatment was needed and how well the eye responded. Children treated at earlier stages generally have better visual outcomes than those treated when the disease was very advanced. The ophthalmologist who has followed your child can give the most accurate picture.

Why does my baby need more than one eye exam? Isn’t one enough?

ROP changes over time. A baby whose eyes look fine at the first exam may develop ROP later, and a baby with mild ROP can either regress or progress. Repeated exams allow the doctor to track the direction of change and act at the right moment. Missing an exam in the active phase can mean missing the treatment window.

Can ROP come back after treatment?

Yes, particularly after anti-VEGF injections. The medication blocks abnormal vessel growth for a time, but if the underlying retinal vessel development has not caught up by the time the medication wears off, ROP can recur. This is the reason for prolonged follow-up. Recurrence can be treated, often successfully.

Does ROP affect only the eyes, or other parts of the body too?

ROP itself is a disease of the eye. However, the underlying prematurity that caused ROP can also affect other organs, particularly the lungs and the developing brain. This is why premature babies need broader developmental follow-up alongside their eye care.

How long will my child need to see an eye doctor?

Most children with a history of ROP — whether treated or not — benefit from periodic eye examinations through childhood and into the teenage years. Some will need lifelong follow-up if there are residual changes in the retina. The ophthalmologist will set a schedule based on your child’s specific situation.

My baby needs treatment far from home. Can the eyes wait until we travel?

This depends entirely on the stage and zone of disease. Some ROP requires treatment within 48 to 72 hours of meeting criteria, and any delay can change the outcome. Other situations allow more time. The treating ophthalmologist is the right person to advise on what kind of timeline applies. If travel is being arranged, share the urgency with the team so that planning can match the medical priority.

Will my child be told they had ROP when they are older?

It is helpful for children to know their medical history as they grow, including any eye conditions in infancy. As your child becomes a teenager and then an adult, this information will guide their own eye care, including whether they need more frequent retinal checks. Keep records of treatments received, including the type, dates, and follow-up findings.

Conclusion

Retinopathy of prematurity is a condition that has changed dramatically in the era of careful screening and effective treatment. Most premature babies who are screened do not need treatment at all, and most who do are treated successfully. For families, the path through ROP can feel uncertain, but it is also one of the clearest examples in medicine of how attentive, timely care protects the future of a child.

Whether your baby is being screened for the first time, has just received treatment, or is now in long-term follow-up, the principles are the same: keep every appointment, ask the questions you need to ask, and partner with the team caring for your child’s eyes. With that partnership and the steady progress of paediatric eye care, the outlook for children with ROP today is brighter than it has ever been.