What is chorion villus sampling?
CVS is a diagnostic test carried out during early pregnancy to detect chromosomal and genetic conditions such as:
- Down syndrome (Trisomy 21)
- Edwards syndrome (Trisomy 18)
- Patau syndrome (Trisomy 13)
- Other genetic disorders, including single-gene conditions (e.g. sickle cell disease, thalassaemia, cystic fibrosis)
This test is usually recommended if:
- You’ve had a high-chance result from the NIPT or nuchal scan
- There is a known genetic condition in your family
- You want a definitive answer early in pregnancy
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What happens during a CVS?
CVS is usually performed between 11 and 14 weeks of pregnancy. The procedure involves taking a small sample of tissue (chorionic villi) from the placenta using a thin needle inserted through the abdomen. This is done under continuous ultrasound guidance.
The procedure takes just a few minutes and is performed by one of our highly experienced fetal medicine specialists.
Is CVS safe?
CVS is generally safe, but as with any invasive procedure, there is a small risk of miscarriage. At The Fetal Medicine Centre, we use the latest ultrasound technology and specialist techniques to minimise this risk as much as possible.
Our doctors will discuss the benefits and risks with you in full before you decide to consent and proceed.
How long do CVS results take?
There are two types of results:
- Rapid test (QF-PCR) – available in 2–3 working days. This looks for the most common chromosomal conditions (trisomy 21, 18, and 13).
- Full karyotype or microarray – available in 10–14 working days. This provides a detailed analysis of all chromosomes and can detect rarer conditions or deletions/duplications.
We will talk you through which type of analysis is most appropriate for your circumstances.
What is the cost of CVS?
Please refer to our Fees & Services page for current pricing, or contact our team directly for more information.
