percept™ NIPT Testing
percept™ is an Australian non-invasive prenatal test (NIPT) offered by Victorian Clinical Genetics Services (VCGS). This is a screening test for identifying pregnancies at increased chance of having a chromosome condition such as Down syndrome, Edwards syndrome and Patau syndrome.
The NIPT test involves a simple blood draw from the pregnant person. During pregnancy, a small amount of the baby's DNA circulates in the mother's bloodstream. NIPT analyzes this fetal DNA to detect any abnormalities. Since NIPT is a screening test, a positive result doesn't necessarily mean the fetus has the condition in question; it indicates an increased risk.
If NIPT results indicate a higher risk, further confirmatory testing such as Amniocentesis or CVS may be recommended.
5 Things to know about percept NIPT
percept NIPT is a screening test that can tell you the chance your pregnancy may have a chromosome condition.
percept NIPT gives high chance or low chance results. Most women/couples receive a low chance result.
Some women/couples receive high chance results. Further testing will be offered to clarify the result. This is because a high chance result does not mean the baby definitely has the condition.
percept NIPT does not identify all genetic or chromosome conditions.
It is not 100% diagnostic, so it is really a screening test.
It has a better detection rate than any other screening test.
How can I access NIPT through Melbourne Ultrasound for Women?
Screening can be performed any time from 10 weeks of pregnancy. Results are available in 3-5 business days (from when the laboratory receives the sample).
Your doctor can provide you with the request forms and discuss these tests with you.
Alternatively they may give you a referral to see us at 10 weeks to have an ultrasound and provide you with a request form.
At 10 weeks we will do an ultrasound to check that your pregnancy is progressing normally, exclude multiple pregnancies and confirm your dates before you have the NIPT test done.
We do not have pathology collection available at our clinic so you will need to locate your nearest pathology for blood collection.
A list of VCGS pathology locations can be found below:
Why has my doctor asked me to do an Ultrasound before my NIPT test?
Knowing the accurate gestational age of the pregnancy is crucial for interpreting the NIPT results accurately.
An ultrasound can provide an estimate of how far along you are, helping the healthcare provider select the appropriate test parameters.
An ultrasound can confirm the viability of the pregnancy, ensuring that there is a developing fetus with a heartbeat. This is important because NIPT relies on analyzing fetal DNA in the mother's bloodstream, so it's essential to ensure there's a viable pregnancy before proceeding with the test.
FAQs
How does NIPT work?
As a baby grows, the placenta releases small fragments of DNA known as ‘cell-free fetal DNA’ (cfDNA) into the mother's bloodstream. This cfDNA from the placenta can be sequenced.
If the baby has a chromosome condition, there will be an increase or decrease in the amount of this cfDNA sequence. For example, if the baby has Down syndrome, (an extra copy of chromosome 21), there will be an increase in the amount of cfDNA sequence from chromosome 21.
What do my results mean?
percept screening results are reported as:
Low risk
Most results will be low risk. This means it is very unlikely the pregnancy is affected by one of the specific conditions screened for. There is always the chance that the result is a ‘false negative’, but this is very rare. Low risk does not mean ‘no risk’. Other conditions not identified by NIPT may be present.
High risk (increased chance)
A high risk result does not mean the pregnancy is definitely affected by a particular condition. It means there is an increased chance. There is always a chance that the screening result is a ‘false positive’. Diagnostic testing will be offered to confirm the result or to reassure that the pregnancy is not affected.
No result
percept test failure rates are very low (<0.2%). They sometimes occur if there is not enough cfDNA to test, or if the sample was poor quality. In this case, the laboratory will request a repeat sample for testing at no additional charge.
Is NIPT different to Maternal Serum Screening?
NIPT is a more accurate type of screening test for Down syndrome than maternal serum screening (MSS). NIPT also looks for a much wider range of chromosome conditions than MSS.
However, NIPT is more expensive and is not covered by Medicare or private health insurance. MSS is a very good screening test which is less expensive and partially covered by Medicare.
Some women choose to have MSS as their first test and then follow up with NIPT only if they receive a ‘screen positive’ result from MSS. Many women choose just to have NIPT.
If you have NIPT as the first test, you do not need MSS as well. We recommend all women have a 12 week ultrasound scan to provide information about the structural development of the baby.
Do I still need other prenatal screening if I choose NIPT?
NIPT is one tool in prenatal screening, but it doesn't replace other important tests like ultrasounds. Depending on your healthcare provider's recommendations and your risk factors, additional screenings might still be advised.
When will I get my results?
percept results are usually available from within 3-5 working days after your sample arrives at VCGS (not from when it was collected).
We will send you an SMS when the result has arrived at our practice.
Should there be any complications with your results our Doctor will contact you on the mobile number you have provided.
What happens if my result is High Risk?
Receiving a high chance result does not mean your pregnancy definitely has a chromosome condition; it means there is an increased chance. For all high chance results, a VCGS genetic counsellor will contact your referring doctor to discuss further testing options, such as diagnostic testing (using a CVS or amniocentesis).
Remember, screening tests do not provide a definitive (yes or no) answer. Diagnostic testing is the only way to confirm the presence of a chromosome condition or to reassure a pregnancy is not affected.
Ultrasound monitoring may also be offered to check for physical abnormalities that can be common markers for chromosomal abnormalities.