Having the test
Having a NIPT is easy. It requires a simple blood draw, which can be done as soon as you have reached 10 weeks' gestation.
Four simple steps
- Visit your doctor to discuss NIPT and decide whether it is right for you. Your doctor will provide you with a completed request form for the test
- Visit sonicgenetics.com.au/payment to arrange payment for your NIPT and book a blood collection at your nearest collection centre
- Once 10 weeks gestation is completed or later, have the simple blood test
- Results will be sent to your doctor within 3 - 8 business days from the date your sample arrives at one of our accredited Australian testing laboratories
We recommend that prior to having NIPT, the woman has an ultrasound to confirm the gestation of the pregnancy, the number of fetuses and that the pregnancy is viable. Please note that NIPT is not a test of fetal viability as a demised fetus will continue to release DNA into the mother’s circulation.
NIPT cannot be used:
- if the pregnancy has three or more fetuses
- in the presence of a demised fetus
- if the mother has an abnormal number of chromosomes, bone marrow or organ transplant, or cancer.
NIPT delivers clear answers as early as the first trimester with a single blood draw
The result of your NIPT will be sent to your requesting doctor for review. Your doctor will be able to take you through your results and explain the full details of our report.
In at least 99% of women, the NIPT report provides a clear indication regarding the chance of specific chromosome conditions being present in the developing baby. Please note that NIPT is a screening test i.e. it is just one of the tests that your doctor will discuss with you in assessing the health of your pregnancy. Your NIPT result needs to be considered in conjunction with other test results. Your doctor may recommend other investigations.
If your report indicates that there is an increased probability of a specific chromosome condition, Sonic Genetics can provide genetic counselling free of charge for Australian-based patients that have prepaid Sonic Genetics for the NIPT. We would provide directions about accessing this service to your doctor.
Can NIPT ever be wrong?
There are rare occasions when the NIPT result does not accurately reflect the chromosomal status of the fetus.
In approximately 1:2,000 pregnancies, the cells of the outer placenta have an abnormal number of chromosomes compared to the developing fetus. This can potentially cause a false positive i.e. NIPT identifies a chromosome abnormality in the placental DNA floating in the mother’s plasma but the baby turns out to be fine. For this reason, an NIPT result that indicates a high probability of there being a chromosome condition must be confirmed by invasive genetic testing (CVS or amniocentesis) before making any major decision about the pregnancy.
Conversely, in up to 1% of fetuses which have a major chromosome condition, the placental chromosomes may be normal. NIPT may correctly report that there is no evidence of a chromosome condition in the mother’s blood sample, but the developing fetus actually has a chromosome condition i.e. a false negative result. For this reason, a “low risk” must be assessed with the results of other investigations arranged by your doctor.
These false positive and false negative results are due to the biological complexity of pregnancy, and occur with any form of NIPT. They do not reflect technical failings within the laboratory.
Does NIPT test for everything?
No. NIPT tests for the specific conditions nominated on the request form by your doctor. These are common conditions, but they are not the only conditions that may affect a developing fetus.
What if NIPT cannot make an assessment?
In up to 2% of patients, we may not be able to provide an assessment regarding every chromosome condition requested. There may be insufficient fetal DNA in the mother’s blood for NIPT to give an accurate result, or there may be uncommon yet benign variations in certain DNA sequences in mother or fetus that compromise the accuracy of the test. Depending on the underlying cause, we may recommend a re-collection with reanalysis (at no extra cost to you). In approximately half of those women who have a second collection, we are able to provide a definite result.
If we are unable to provide an assessment regarding the three common trisomies after one sample collection (or after two, if the laboratory requests a second collection), the credit card holder that paid for the test will be refunded in full upon request; please contact us on 1800 010 447.