Chorionic villus sampling test (CVS)

The test involves removing and testing a small sample of cells from your placenta (the organ linking your blood supply to your unborn baby's). Your consultant will do this using ultrasound guidance.

A sample of placental tissue is taken using a needle inserted through your abdominal wall or with a pair of fine forceps (like tongs) through your cervix. The tissue collected is then tested for DNA (genetic or chromosomal) abnormalities. Your preliminary results are usually available within two to three working days with a full report available within two to three weeks.

Your consultant will let you know how best to prepare for this test.

You will be able to leave and carry on with your day immediately following the test. The initial results should be available within three working days and this will tell you whether a major chromosome condition such as Down's, Edwards' or Patau's syndrome, has been discovered.

Rarer conditions may take two to three weeks to be diagnosed. If the test shows that your baby has a genetic or chromosome condition, your consultant will discuss the results with you. They will also let you know all of the options open to you.