What is coloboma?

A coloboma is caused when a baby's eyes do not develop properly during pregnancy. The eyes develop between the fourth and anything up to the fifteenth week of pregnancy, though development is usually completed at around eight weeks. This condition occurs in about 1 in 10,000 births.

Coloboma can affect one eye (unilateral) or both eyes (bilateral). Coloboma can affect a number of different parts of the eye. Coloboma does not mean that there is a hole in the eye, but that certain structures or parts within the eye did not fully form.

More information can be found on our coloboma web page.

We also have a coloboma factsheet:

For more information about coloboma and other eye conditions please contact our Helpline:

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