".To be told your baby has a cyst or cysts in its brain is scary. In fact, a choroid plexus cyst is just a collection of fluid in the part of the brain which makes the fluid that cushions the brain and spinal cord. The 'cyst' is just a small build-up of fluid as it moves through the connecting tubes. As the baby grows, so the tubes get bigger and the fluid moves on. Cpcs are almost always gone by 24 weeks and do no harm to the baby's brain.
Cpcs look like black spots in the hemispheres of the brain and were first seen in the 1980s. They caused a scare initially because many babies with edward's syndrome were found to have cpcs. However, research has shown that edward's babies also have other abnormalities, such as strawberry-shaped heads (see image 1, below), overlapping fingers and abnormal feet, heart, kidney or abdominal problems.
It is now known that one per cent of all babies have one or more cpcs in early pregnancy (see image 2, below). In the absence of other markers (isolated cpcs) they are insignificant and sonographers in many hospitals do not even mention them any more. "