Retinopathy of Prematurity


Retinopathy of prematurity (ROP) is an eye disease that occurs in a small percentage of premature babies where abnormal blood vessels grow on the retina — the light-sensitive layer of cells lining the back of the eye that help us see. The image shows examples of normal and abnormal blood vessel growth.

ROP occurs more frequently in smaller babies with very low birth weight or of an earlier gestational age. For instance, a 28-week premature baby has a greater risk of developing ROP than a 32-week premature baby.

In some cases, the abnormal blood vessels may shrink and go away without treatment. In other cases, the vessels may continue to develop and serious eye and vision problems may occur, such as:


There are no symptoms of ROP and infants must be screened by an ophthalmologist.


Doctors do not know for certain what causes ROP. Blood vessels in the eye normally finish developing in the last few weeks before birth. Premature infants, however, leave the protective uterus before blood vessels of the eye have had a chance to fully develop.

The infants are then exposed to elements, such as medication, high levels of oxygen, and light and temperature changes. These factors may interfere with the normal development of blood vessels in the eye and cause ROP.

Other factors that may have an effect on ROP development include:

  • ‍Low birth weight
  • Low gestational age
  • Use of supplemental oxygen after birth
  • Vitamin E deficiency
  • Race (Caucasians are more at risk than African-Americans)
  • Anemia
  • Respiratory complications


Premature babies should be screened for ROP and all other at-risk illnesses shortly following birth. An ophthalmologist can diagnose ROP during an examination of the baby's eyes in a hospital's neonatal intensive care unit or nursery.

Sometimes ROP may not be detected until several weeks after birth. Therefore, premature babies at risk for ROP should also have their eyes examined by an ophthalmologist four to six weeks following birth.

If ROP is diagnosed, the exams should continue regularly until the abnormal blood vessel growth goes away on its own or is adequately treated by the ophthalmologist.


At first, an ophthalmologist may monitor ROP to see if it goes away on its own. If abnormal blood vessels continue to grow, the infant’s eyes must be treated.

The ophthalmologist may treat ROP in one or more of the following ways:

  • ‍Laser treatment
  • Freezing treatment (cryotherapy)
  • Medication eye injections

With laser treatment, the ophthalmologist uses a laser to burn away the edge of the retina. With freezing treatment (cryotherapy), the surgeon uses a freezing cold instrument to destroy part of the retina. Both of these treatments target very specific parts of the retina to try to stop abnormal blood vessel growth.

Research is also underway on medications for ROP. These drugs are injected (given as shots) into the eye to stop unwanted blood vessel growth.

As babies with ROP grow, they need to be checked regularly by an ophthalmologist for vision problems. Having ROP can lead to being nearsighted, or having a detached retina, lazy eye or misaligned eyes. It also increases the risk of having glaucoma. These problems may be treated by:

  • ‍Wearing eyeglasses
  • Taking eye drops
  • Putting a patch on one eye
  • Having eye surgery
American Academy of Ophthalmology