FAQ: Non-invasive Prenatal Testing (NIPT)

FAQ: Non-invasive Prenatal Testing (NIPT)

January 20, 2021

Learn more about the NIPT test offered by Melio.

What is NIPT and what does it screen for?

Non-Invasive Prenatal Testing (NIPT) is a screening test that looks at the baby’s DNA in the mother’s bloodstream to identify if the baby is affected by certain chromosomal abnormalities. It's a very accurate test which only requires a small blood sample taken from the mother.

The test is analysed at Nottingham University Hospitals NHS Trust using the Vanadis® NIPT system from PerkinElmer. The Vanadis® NIPT system is a CE marked in vitro diagnostic product in accordance with European directive 98/79/EC.

Is the Vanadis NIPT test safe?

The test requires a blood sample taken from the mother’s arm and carries no risk to the mother or baby.

Which chromosomal abnormalities will NIPT detect?

The Vanadis NIPT test is a targeted test which will identify the chance that the baby is affected by Down’s, Edwards’ and Patau’s Syndromes. The test will not screen for all possible chromosomal conditions.

Down's Syndrome is a genetic condition caused by an individual having an additional copy of chromosome 21 (three copies of chromosome 21 are present instead of two). It is the most common chromosomal condition seen in children and adults. Down’s Syndrome is characterised by learning difficulties but can also be associated with an increased chance of other medical conditions. As it is a variable condition it is not possible to know how affected a baby will be as some adults are able to lead a fairly independent life although many need continued support.

Edwards' and Patau's Syndromes are very rare conditions. Edwards’ Syndrome is caused by an individual having an additional copy of chromosome 18 and Patau’s Syndrome is caused by an individual having an additional copy of chromosome 13. Both conditions are life-limiting and many affected babies die during pregnancy or shortly after birth.

How accurate is the Vanadis NIPT test?

The traditional serum screening test consists of a blood test and an ultrasound scan. This test is less sensitive than NIPT as it only detects 86% of babies with Down’s Syndrome and 80% of babies with Edwards’ and Patau’s Syndromes. The Vanadis® NIPT test sensitivity is shown in the table below.

The Vanadis® NIPT test can also determine the sex of your baby with 99.6% sensitivity. As fetal sex determination test option does not have a medical purpose, it does not meet the definition of an in vitro diagnostic device.

Who can have the Vanadis NIPT test?

The test is available to all women from 10 weeks of pregnancy for all single, twin and IVF pregnancies. The NIPT test is not suitable if you meet any of the following criteria

  • have cancer or chromosomal abnormalities including Trisomy 13, 18 and 21

  • have received an organ transplant or received stem cell therapy or immunotherapy within the last 12 months

  • have had a blood transfusion within the last 3 months

  • have a multiple pregnancy greater than twins

  • have a vanishing/demised twin pregnancy

How are results reported?

Low chance: this means that it is very unlikely that the baby is affected by Down’s, Edwards’ or Patau’s Syndrome.

Increased chance: this means that there is an increased chance that your baby is affected by Down’s, Edwards’ or Patau’s Syndrome. All increased chance results should be discussed with your midwife and confirmed by an invasive diagnostic test which could be chorionic villus sampling (CVS) or amniocentesis. Confirmation is required, as in a very small number of cases the DNA from the placenta may not represent the DNA of the baby. Your midwife will be able to support you so that an informed decision can be made.

Failed test: this means that a result has not been able to be produced. In a very small number of cases it is possible that there is not enough baby’s DNA in the mother’s blood to produce a result. The Vanadis NIPT test have a low failure rate at about 0.2%. This is considerably lower than most other NIPT tests on the market, which in some case can have a failure rate as high as 6.4%.

Inconclusive result: this means that the result is not clear and a result cannot be produced. This is unlikely to occur.

Two 10 mL samples of blood will be collected for each NIPT test. If a test produces a “failed” or “inconclusive result”, the second sample will be tested at no additional cost. If the second test does not produce a result (which is rare), another blood sample will be required. In these cases further payment will be required.

How can I get a test?

Melio offers the Vanadis® NIPT test to our customers in collaboration with the Clinical Pathology department at Nottingham University Hospitals NHS Trust. You can choose to either have an In Clinic test or an At Home test.

Here is how it works:

Buy the test

When you buy your NIPT test from Melio's website, you'll be asked to register an account with us. After purchase, you'll be asked to fill out a questionnaire with details about you and the pregnancy. If you have purchased an At Home test, you'll also be asked to fill in your address and preferred date and time for the blood draw.

Book your appointment

Once the purchase is completed, you'll receive an order confirmation email with your unique order code. If you are taking an In Clinic test, you will be asked to book an appointment for the blood draw at one of our partner clinics. If you are taking an At Home test, you will be contacted by phone to finalize the booking process after you have completed the questionnaire. Note that the test should be taken from 10 weeks of pregnancy, so take this into account when booking your time slot. You don't need to be fasting before this test, so you can choose at time slot at any time of the day.

Take the test

At the appointment, you will need to show your order code and a valid photo ID. You don't need to bring anything else, all supplies will be available at the clinic or sent to you in a test kit depending on the test that you choose. It's recommended to stay well hydrated before a blood draw, so drink an extra glass of water if you can.

At the appointment the phlebotomist may ask you a few more questions, including your height, current weight and how far along the pregnancy is.

Get you results

When the laboratory has analysed your sample, the results will be sent to Melio together with a detailed PDF report of the analysis performed. One of Melio's doctors will also review your results and post a personalised medical comment explaing the results in your Melio account.

When your results are ready, you'll receive an SMS notification to login to your Melio account to access the results. Results are normally delivered in 5-11 days.

About the laboratory

The Clinical Pathology department at Nottingham University Hospitals NHS Trust has run a successful antenatal screening service for Nottinghamshire, Lincolnshire and Sherwood Forest for over twenty-five years.

The laboratory is fully UKAS accredited (Number 8848) and is compliant with the NHS Fetal Anomaly Screening Programme Service Specification No. 16 and the NHS Fetal Anomaly Screening Programme Handbook for Laboratories (2018). The laboratory participates in external quality assurance and DQASS quality schemes.

The laboratory has a dedicated team of experienced clinical scientists who are fully trained and competency assessed. Laboratory representatives attend all national Fetal Anomaly Screening Programme and Down’s Quality Assurance Support Service (DQASS) training events.

The laboratory has utilised PerkinElmer equipment for over twenty years and was one of the first to adopt the Vanadis® technology for NIPT screening.

Further recommended resources

Antenatal Results and Choices (ARC): National charity offering non-directive information and support to parent before, during and after antenatal screening. www.arc-uk.org Helpline: 0845 077 2290 or 0207 713 7486 (Open Monday to Friday 10am – 5.30pm)

Down’s Syndrome Association: www.downs-syndrome.org.uk 0333 1212 300 (Open Monday to Friday 10am – 4pm)

Support Organisation for Trisomy 13/18 (SOFT): www.soft.org.uk

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