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Non Invasive Prenatal Testing in London (NIPT)

We combine advanced NIPT for Down’s syndrome with our expert ultrasound scan to check your baby’s health as early as possible. The best time to take NIPT is with a 10 Week Scan.

We have options of NIPT for DiGeorge and Noonan syndromes, cystic fibrosis, microdeletions and other conditions.

The best NIPT in London: Summary

We exclusively partner with NIPT test providers that have undergone thorough evaluation by our expert team, ensuring their lab performance meets our stringent standards.

  • Best NIPT for Down’s syndrome: PRENATALSAFE
  • Comprehensive NIPT: SMART TEST
  • Cost-effective NIPT: UNITY
  • Rh-negative mothers: UNITY
  • Cystic fibrosis NIPT: UNITY
  • DiGeorge syndrome NIPT: PANORAMA TEST
  • Microdeletions: SMART TEST
  • Discontinued in the UK: HARMONY TEST

SMART TEST: the most comprehensive NIPT package for trisomy 21 and RARE DISEASES

Panorama NIPT London

Our NIPT + Early Anomaly Scan always incorporates chromosomal anomaly and structural screening from as early as 10 weeks

NIPT at London Pregnancy Clinic

  • Most accurate Down’s syndrome screening tests currently available

  • Advanced structural and chromosomal screening tests from 10 weeks: at least 3 chromosomal conditions (by NIPT) + at least 10 severe structural anomalies (by scan)

  • Choose between a Panorama NIPT £590 (from 9 weeks) and a PrenatalSAFE £540 or Unity NIPT £490 (10 weeks)

  • SMART TEST: We offer the most cutting-edge NIPT screening options, capable of detecting up to 100 different rare diseases, such as Di George, Turner, and Noonan syndromes, cystic fibrosis, microdeletions and other serious diseases

  • Scans and NIPT appointment with our fetal medicine specialists with extensive NHS and international experience.

  • PrenatalSAFE NIPT results in 2-4 working days 

  • Same day, evening, and weekend appointments

  • Optional accurate gender reveal included in the price 

  • Latest 3D/4D ultrasound technology

  • Scan report, videos and images sent straight to your smartphone

  • 5* rated service on Google, Trustpilot & Doctify

NIPT Testing Explained

What is NIPT (Non-Invasive Prenatal Screening)?

Non-invasive prenatal screening is an advanced screening test predominantly for 3 chromosomal anomalies:

  • Down’s Syndrome (Trisomy 21 – >99% detection rate)
  • Edward’s Syndrome (Trisomy 18 – 97.4% detection rate)
  • Patau’s Syndrome (Trisomy 13 – 93.8% detection rate)

Harmony NIPT published the figures above which represent detection rates.

The test is highly accurate with false positive rates <0.1% for all 3 trisomies. Detection and false positive rates are calculated at a risk cut-off of 1/100. The test can also detect the fetal sex with >99% accuracy.

10 weeks is the best time to perform NIPT

10 weeks is the best time for your NIPT because:

  1. You prefer to be reassured regarding Down’s syndrome as early as possible
  2. We perform your earliest fetal structural anomaly scan at 10 weeks which will exclude severe not-chromosomal defects
  3. In case of no-call NIPT results of the test you have plenty of time to to retake the test and have alternative screening for Down’s syndrome by Combined Test
  4. In case of high-chance NIPT results you can perform CVS (invasive test) to confirm or exclude the chromosomal problem at earliest possibility (usually at 11-12 weeks).
  5. In case of an abnormal finding in our 10 Week Scan, we will assist you in an urgent referral to Fetal Medicine Unit without wasting your time or money for inappropriate NIPT. It is well-recognised that NIPT is unsuitable test in the case of structural fetal anomaly
  6. It is possible to perform Panorama Test from 9 weeks, however in this case structural assessment of the baby can be limited
Tests available at London Pregnancy Clinic

‘PrenatalSafe NIPT’, developed by European NIPT leader Eurofins employs cutting-edge genomics technology and a proprietary test algorithm, ensuring reliable screening for common chromosomal anomalies like Down’s syndrome (trisomy 21), Edwards syndrome (trisomy 18), and Patau syndrome (trisomy 13). PrenatalSafe stands out due to its minimal maternal blood requirement (just one tube) and impressively low no-call rates (less than 2%). This makes PrenatalSafe an extremely effective blood test for Down syndrome. It’s uniquely effective in situations involving ‘vanished’ twins where other NIPT options may not apply. Additionally, PrenatalSafe offers high accuracy in optional fetal gender determination.

PrenatalSafe is our top choice for NIPT in London, driven by its utilisation of advanced technology, minimal no-call results, and a swift turnaround time, thanks to its UK-based lab facility. We recommend PrenatalSafe if you want to complete a Down syndrome baby scan.

‘Panorama AI’ is a test developed by Natera (US), a pioneer in the field. New upgraded Panorama AI algorithm uses a combination of artificial intelligence (AI) with Natera’s proprietary genetic methodology to improve both accuracy and the positive predictive value for an extended range of genetic conditions. Panorama NIPT is our best choice for DiGeorge (22q del) screening and for twin pregnancies. It also works from 9 weeks of gestation.

‘UNITY’ (coming soon) is the principal new concept NIPT which has been recently developed by BillionToOne Inc in California and now getting major attention in US. We are proud that we are the first clinic in London to offer this NIPT in the UK. As a new player on the market, Unity offers a cost-effective option for basic screening of Down syndrome and other common chromosomal abnormalities. UNITY Carrier Screen offers a screen for a range of genetic disorders, including cystic fibrosis (CF), spinal muscular atrophy (SMA), sickle cell disease, and other fetal red cell genetic disorders. 

‘Harmony test‘ was a brand name for Roche’s NIPT. The test was developed by start-up Ariosa (US) more than 10 years ago. The analysis was performed in London by TDL Genetics. This service was terminated by TDL due to problems with the test performance.

Please find a comparison table between the tests below. 

How is the test performed?

Our fetal medicine doctor will initially conduct an anatomical examination of the baby to check for structural anomalies and take some measurements for the NIPT test. 

Once the clinician is satisfied with the baby’s normal structural examination, they will proceed with a consultation about NIPT to answer your questions about every aspect of the test. 

Finally, our friendly phlebotomist will take the mother’s blood sample from the arm – just like any routine blood test you may have done elsewhere.

Our staff then process the maternal blood samples and will send them to the lab soon after your appointment. Now all there’s left to do is to wait for a call from us!

Why do I need to have an ultrasound scan with NIPT?

Ultrasound is a vital part of fetal screening. The laboratory requires a confirmation of viability and gestational age by the clinic submitting each NIPT

NIPT is a highly effective screening test for 3 chromosomal anomalies plus some other genetic conditions (panorama only), however it is unable to screen for structural anomalies such as heart or brain defects which are more common and often more serious than Down’s syndrome.

Here at London Pregnancy Clinic, we specialise in early detection of fetal anomalies, the fetal heart and the fetal brain. We can detect some severe fetal anomalies as early as at 10 weeks. Visit our scans page to find out which scan you will be having along with NIPT. Generally, we believe that our 10-week scan is the best option.

If you choose to have a panorama test at 9 weeks, we will also perform an expert structural scan for your baby (embryo), however this scan will be understandably limited due to small size and developmental immaturity of the baby.

10 Structural Anomalies we Screen for at 10 weeks

With our expertise and technology, we can screen for structural anomalies from 10 weeks (approximate prevalence in the first trimester):

  • Acrania (1:1,000)
  • Alobar Holoprosencephaly (1:1,300)
  • Spina Bifida (1:2,000)
  • Absence of arms, hands, legs or feet (1:2,000)
  • Encephalocele (1:5,000)
  • Exomphalos (Omphalocele) with liver (1:3,500)
  • Amniotic Band Anomaly (1:7,000)
  • Body Stalk Anomaly (1:7,500)
  • Sirenomelia (1:60,000)
  • Conjoined Twins (1% of monochorionic twins)

In comparison, the prevalence of the chromosomal conditions screened for by NIPT:

  • Down’s Syndrome (1:700)
  • Edward’s Syndrome (1:1400)
  • Patau’s Syndrome (1:5000)

If you take the test at 12+ weeks we are able to screen by ultrasound for >100 structural fetal anomalies, however we may lose few advantages of early NIPT.

Harmony NIPT Scan

10 Weeks Scan & NIPT

The best selection of advanced NIPT and ultrasound packages in London



Prenatal SAFE

Panorama AI

Panorama AI
Most advanced NIPT

Smart Test®

Smart TEST®
As early as…
  • 10 weeks

  • 9 weeks

  • 10 weeks

Turnaround (Working Days)
  • 2-4

  • 5-7

  • 7-22

Lab Location
  • UK

  • US

  • UK+EU

No Call Results
  • 0.5%

  • 1%

  • 0.5%

Redraw Rate
  • 2%

  • 3%

  • 2%

Down, Edwards, & Patau Syndrome
Di George Syndrome (22q del)
Turner Syndrome (45X)
  • *

Sex chromosomes aneuploidies
All chromosomes
Chromosomal deletions & duplications
  • 5 (+£200)

  • 9

Inherited monogenic disorders 
Important Genetic syndromes
Comprehensive anomaly Ultrasound screening
Fetal echocardiography
Fetal sex reveal (optional)
Scan & NIPT price
  • £540

  • £590

  •  from £1690 **

  • £790 for Microdeletions

  • **introduction offer

Best overall NIPT
Weeks 6-9


PrenatalSafe uses advanced genomics technology and a unique test algorithm. This NIPT offers secure performance when conducting a Down syndrome pregnancy test. In addition to Down’s (trisomy 21), this is a specialist test for Edwards (trisomy 18), and Patau (trisomy 13) syndromes, with the option to determine fetal sex.

Currently, we consider PrenatalSAFE as the best option for NIPT in London, because it is convenient, requires only one blood tube, and offers quick, reliable results with a very low no-call rate (0.5%).

Read more…

With 22q del
Week 10 & 11

Panorama AI

Panorama NIPT is a globally renowned advanced NIPT with a strong reputation for Down’s syndrome screening. Its standout feature is the validated capability to screen for Di George syndrome (22q11 microdeletion syndrome or 22q del), a chromosomal disorder impacting heart development and potentially causing intellectual disability, behavioural issues, and other abnormalities. This syndrome, affecting 1 in 2000 babies, is the second most common chromosomal condition after Down’s syndrome. 

Panorama AI however has a long turnaround time of up to 2 weeks due to international shipping to US-based lab.

Read more…

Cost-effective NIPT
Weeks 12 – 16


UNITY Aneuploidy Screen is a new player in the NIPT market, and it offers very competitive pricing, making it the best cost-effective option for secure screening of Down’s syndrome and other common chromosomal abnormalities.

For expectant mothers with Rh negative blood group, UNITY Rh is particularly valuable as it can identify the fetal Rh blood group.

UNITY Carrier Screen stands out among other NIPTs as it can screen for a range of severe genetic disorders, including cystic fibrosis (CF), spinal muscular atrophy (SMA), sickle cell disease, and other fetal red cell genetic disorders.

Read more…

Comprehensive NIPT
Weeks 20-25

Smart Test

SMART TEST represents the unique and most advanced option of expert scan and extended NIPT package available. SMART TEST screens for:

  • 22 chromosomal anomalies (including Down’s syndrome)
  • 9 clinically significant NIPT microdeletions (including microdeletion DiGeorge syndrome)
  • 44 different genetic diseases (including Noonan syndrome)
  • 5 inherited single-gene disorders (including cystic fibrosis genetic testing)
  • Sex chromosome anomalies (including NIPT test for Turner syndrome)
  • Majority of severe structural anomalies (including spina bifida)
  • Majority of severe heart defects (including transposition of great arteries)

Read more…

Cancelled NIPT
Weeks 26 – 29

Harmony Test / TDL NIPT

Introduced by TDL (The Doctors Lab) a decade ago, the Harmony Test initially gained recognition in London. However, its reputation has been significantly damaged by notable occurrences of inconclusive results, constant delays in NIPT results reporting, an unacceptable failure rate and mistakes in fetal sexing. These lab challenges caused significant emotional distress for expectant parents.

In an unexpected move on August 29, 2023, TDL announced the discontinuation of the Harmony Test on September 13, 2023, and a shift to an alternative NIPT method based on a different technology used by other NHS providers.

Read more…

NIPT for special conditions (advanced or extended NIPT panels)

The perception of NIPT, also known as a pregnancy DNA test, among professionals and patients has traditionally centred around its basic screening capabilities, primarily targeting Down syndrome, Edwards syndrome, and Patau syndrome. This was indeed the case in 2011 when the first commercially available NIPT tests were introduced. However, over the past decade, remarkable advancements in human genomics have emerged, leading to the availability of highly advanced NIPT alternatives.

As the leading NIPT provider in London, the London Pregnancy Clinic has taken the initiative to review of all commercially available advanced NIPT options. Our aim is to meticulously select the most optimal options for each specific condition, ensuring the best possible care for expectant mothers and their babies.

Please note that most extended NIPT options are available only for singleton pregnancies.

Below is a list of diseases and conditions for which we offer extended NIPT options.

Rh negative mothers


UNITY can identify the fetal Rh blood group starting from 10 weeks of pregnancy. This information is essential for determining whether Anti-D injection, a preventive treatment, is needed. This makes UNITY a unique choice for Rh negative mothers.

Rare diseases

Smart Test

Rare diseases are a leading cause of infant mortality and lifelong disability.

SMART TEST uses the most advanced ultrasound and genomic technology to screen for more than 100 rare diseases and anomalies.

Increased NT

Smart test

Increased NT (nuchal translucency thickness) is associated with various chromosomal and genetic conditions and fetal structural anomalies. SMART TEST is specially designed for early assessment of fetuses with increased NT. Please note that SMART TEST can not completely replace invasive testing.

DiGeorge syndrome

Panorama AI

Di George syndrome is caused by the absence of a specific segment of chromosome 22, leading to a severe condition that often impacts heart development and can be linked to varying degrees of intellectual disability, significant behavioural issues, and other abnormalities. An extensive international study confirmed that the Panorama test can effectively detect over 80% of fetuses with 22q deletion syndrome.

Fetal anomalies

Smart Test

In cases of fetal anomalies, diagnosing genetic conditions typically requires invasive tests like CVS or amniocentesis. Nevertheless, for parents who are reluctant to undergo these tests due to concerns about the risk of miscarriage, the SMART TEST offers a viable alternative option. Please note SMART TEST provides information about probability (not diagnosis).

Heart Defects

Smart Test

When it comes to fetal heart defects, the conventional approach to diagnose associated genetic conditions involves invasive procedures such as CVS or amniocentesis. However, for parents who are hesitant to undergo these tests due to fears of miscarriage, the SMART TEST provides a valid alternative. It’s important to note that the SMART TEST offers probability information rather than a definitive diagnosis.

Cystic fibrosis (CF)

UNITY complete

Cystic fibrosis (CF) is a genetic disorder characterized by the production of thick mucus that can affect the respiratory and digestive systems, leading to various serious health issues. While NHS runs a national screening program for CF, it is conducted after birth when the baby is already born with CF. UNITY offers the option for prenatal screening, enabling parents to obtain essential information about their baby’s health during pregnancy.

Spinal muscular atrophy

UNITY complete

Spinal Muscular Atrophy (SMA) is a rare genetic disorder that causes muscle weakness and atrophy due to problems with motor neurons in the spinal cord. The severity of SMA can vary, however, severe forms can resulted in significant disabilities and even death. CMA results from mutations in the SMN1 gene. UNITY’s sgNIPT Reflex technology provides prenatal screening for CMA.

Sickle cell anemia

UNITY complete

Sickle cell anaemia (SC) is a genetic blood disorder characterized by abnormally shaped red blood cells, leading to pain, anaemia, and other serious health problems. A mutation in the haemoglobin gene causes SC and is particularly common in people with an African or Caribbean family background.

UNITY’s sgNIPT Reflex technology provides non invasive prenatal screening for sickle cell anaemia.


UNITY complete

Thalassemia alpha and beta are inherited blood disorders characterized by abnormal haemoglobin production. Mutations in the haemoglobin gene lead to these conditions.

UNITY’s sgNIPT Reflex technology offers non-invasive prenatal screening for thalassemias. Please note that UNITY is a screening, not a diagnostic test. It provides information about the likelihood or risk of certain genetic conditions but does not provide a definitive diagnosis.


Panorama Ai

Panorama AI is the only test that can distinguish between identical (monozygotic) and non-identical (dizygotic) twins with a high level of accuracy. It is capable of detecting individual fetal fraction for dizygotic twins which is crucial for accurate Down’s syndrome screening for each individual twin. Panorama NIPT also can determine fetal sex for both babies. 

Vanishing twin


PrenatalSafe is effective in situations involving the vanishing twin syndrome.

Panorama test has NOT been validated for this situation.

You will need to delay the NIPT for five weeks to reduce the chance of false positive results associated with vanishing twin syndrome.

Sex chromosome aneuploidy (SCA)


The prenatal detection of Sex Chromosome Aneuploidies (SCAs) is more controversial than autosomal trisomies due to the broad range of possible physical and developmental issues associated with SCAs. Currently NHS does not support screening for SCA. NIPT for SCA is also less accurate and can increase the chance of false-positive results.

Turner syndrome

Optional for all NIPT panels

Turner syndrome is a sex chromosome aneuploidy (SCA) that occurs in females when one of the X chromosomes is missing. This condition can lead to various physical and developmental abnormalities, including short stature, heart defects, and infertility. Unfortunately, NIPT for Turner syndrome has a relatively high chance of false positive results (positive predicted value only 30%).


Panorama AI

Panorama is the only noninvasive method that can identify triploidy.

In most cases, triploidy can be indicated by our expert ultrasound scans due to its distinct ultrasound characteristics that are detectable during the first trimester.



Microdeletions are genetic abnormalities where a small part of a chromosome is missing. They can cause various health conditions and developmental disorders, depending on which genes are affected. SMART TEST screens for 9 common and clinically significant microdeletions. Panorama AI screens for 5 microdeletions. 

Frequently Asked Questions

Your questions answered

Understanding the statistics behind NIPT

It’s important for us that you understand the terminology we use for screening tests:

Detection rate is defined as the fraction of all patients who have the disease and are called positive by the screening test.

Positive Predictive Value or PPV is the proportion of the ‘true positives’ as a proportion of all positive results. As a practical example, the majority of NIPT tests have at least 90% PPV for Down’s Syndrome, meaning that 90% of the fetuses identified as ‘High Probability’ will statistically have the condition. However, the limitation of the test is that in 10% of the cases, it will result in a ‘false positive’ meaning that the test will return a ‘High Probability’ result for a fetus that doesn’t have Down’s Syndrome.

That’s why, for every High Probability result we would refer the patient for a diagnostic test such as CVS or Amniocentesis to verify the results.

In the past there has been confusion about certain aspects of NIPT – please see this notice. If any of the above still unclear to you, please get in touch with us via email or phone and our friendly stuff will be happy to run you through the characteristics of the test.

We wrote a special blog post about understanding the statistics of the NIPT test,  if you would like to find out more, click here.

What is NIPT? What is the Harmony test? What is Panorama NIPT?

Non-invasive prenatal testing (NIPT) or alternatively non-invasive prenatal screening (NIPS) is a screening method for determining the chance that a baby will be born with Down’s syndrome or other chromosomal anomalies. NIPT is based on the assessment of small DNA fragments from a baby’s placenta (named ‘cell-free DNA’ or ‘cfDNA’) that are disseminated in the blood of every pregnant mother. Placental cfDNA is usually identical to the DNA of the baby and testing it provides an opportunity for early detection of particular chromosomal anomalies without harming the baby.

The Harmony Test was a well-known NIPT brand by Ariosa/Roche. The Harmony Prenatal test was a trade name of the cfDNA test. We had the experience of using Harmony for many years. The Harmony Test performed by TDL in London in the last years suffered from a high rate of test failure and inconclusive results. Many our patients were unsatisfied by the test performance. In a dramatic move at the end of August 2023, TDL announced the termination of the test performance in a very short warning period of just two weeks.

Panorama AI NIPT (non-invasive prenatal screening) is an advanced NIPT, based on state-of-the-art algorithms, it has lower sample failure rate comparing with the harmony test and its price is more affordable for the future parents. The limitation of panorama NIPT is its long results reporting time (up to 10 working days) which is a result of sample shipping to US based Lab. 

Although cfDNA is a relatively new genetic test, it has been proven to be superior to any other screening tests for Down’s syndrome, including the combined screening test (CST) used by the NHS. However, NIPT can detect a relatively small proportion (about 15%) of all fetal anomalies, because the vast majority of fetal anomalies are physical (structural) and not chromosomal.

NIPT is a screening test, meaning that NIPT cannot give a definitive answer about whether a baby has Down’s syndrome or other tested chromosomal conditions. If the results are positive (high chance) follow-up invasive testing is needed to get a definite diagnosis. Any invasive testing carries a small risk of miscarriage.

Do you offer Illumina VeriSeq™ NIPT Solution v2?

During September 2023, The Doctor’s Laboratory (TDL Genetics) who had the exclusive rights for performing the Harmony Test NIPT in the UK, announced that it had ceased offering the test. 

As an alternative, the laboratory opted to offer VeriSeq™ NIPT Solution v2 which has been used by other laboratories in the UK for a couple of years. At London Pregnancy Clinic, we chose to use PrenatalSAFE, that uses the same apparatus as Illumina’s NIPT test, but has better validation data and more experience with using the technology.  

Why choose PrenatalSafe NIPT?
  • Advanced genetic technology
  • Whole-Genome Sequencing (WGS)
  • Proved performance for Down’s syndrome screening
  • Less no-call results (<2%)
  • Fast results: 3-5 working days
Why choose Panorama AI?
  • Advanced genetic and artificial intelligence (AI) technology
  • Available from 9 weeks
  • Di George Syndrome (22q del) screening
  • Triplody screening
  • Less no call results (1.4%)
  • Better fetal fraction cutoff (2.8%)
  • Option of additional microdeletions screening (for an additional fee)
  • Option of additional single-gene mutations across 30 genes screening by Vistara NIPT (for an additional fee)
  • Cheaper option at £200 (vs £240)

22q deletion (del) syndrome or Di George syndrome is a genetic condition, which is caused by a small, missing or “deleted” piece of the 22nd chromosome. Unfortunately, that missing piece can affect every system in the human body including the heart (heart defects in 75% babies), palate, immune system, hormones, kidneys and others. It also can affect mental health and is associated with learning and behavioural differences, anxiety, and other mental health issues like schizophrenia (in 25% of adults).

Panorama AI can detect >80% of the fetuses with 22q del with a positive predictive value of 53%. Early detection of 22q del can lead to earlier interventions and better outcomes for affected individuals. For instance, in our clinic, we can perform early fetal echocardiography from 12 weeks to exclude severe heart anomaly associated with 22q del.

For more information, please visit

What are the limitations of Panorama Test?
  • Longer turnaround time: up to 10 working days. This is due to the time taken to transfer the samples to the US based lab.
  • Application of extended diagnostic panels (sex chromosomes, triploidy, 22q del, microdeletions) increase the chances for false positive and inconclusive results. The positive or inconclusive results of the test in some cases do NOT covered by NHS and you may require private genetic counselling and possible private invasive test (CVS or amniocentesis) for your own expense.

Currently NIPT is not routinely offered by the NHS.

The nuchal translucency (NT) thickness measurements scan was developed in the 1990s, and at the time was the best screening option for Down’s syndrome offering about 62% accuracy and a 5% false positive rate. The NHS now offers the ‘combined test’ at 11-14 weeks which includes a nuchal translucency scan along with a blood test (for PAPP-A and HCG proteins) with improved the accuracy of 81% and false positive rate of 4.5%.

NIPT was first introduced in 2011 and was shown to have superior accuracy to the combined test with a 99.99% detection rate and sub 0.1% false negatives. Please note, we still recommend following through with your NHS antenatal appointments, they are important for the continuity of your pregnancy care.

Which chromosomal conditions does the PrenatalSafe Test (instead of Harmony Test) at London Pregnancy Clinic cover?

We offer NIPT for the following:

  • Down’s syndrome (T21)
  • Edwards syndrome (T18)
  • Patau syndrome (T13)
  • fetal sexing

    Some biotechnological companies/manufacturers of NIPT, including Panorama AI and UNITY, which London Pregnancy Clinic offers, have launched commercially available products aiming to screen for sex chromosome abnormalities, microdeletions (including 22q del) and/or single-gene disorders.

    Although the tests are technologically advanced, the peer-reviewed validation data for those tests is patchy, and the accuracy is inferior to the tests for T21, T18 and T13.

    In the UK, the NHS considers the use of those tests controversial and, as such, unlikely to accept a ‘high probability’ or ‘inconclusive’ test results as a referral for further invasive testing or genetic counselling.

    If you choose to have those advanced options, we will guide you and arrange private genetic counselling in the case of high-chance NIPT results. Please note that this can incur additional expenses. 

    Why 10 weeks is the best time to perform NIPT?

    We recommend taking the NIPT along with our comprehensive early anomaly scan (10-week scan) as soon as possible – 10 weeks. Early detection of either chromosomal or structural anomalies allows more time in terms of pregnancy management for those conditions. If your sample fails, you have plenty time for redraw.

    If you’re unsure about the age of your pregnancy, we strongly recommend performing a viability scan with us at around 7-8 weeks of your gestation. The viability scan will date your pregnancy and we can arrange the earliest possible appointment for your NIPT.

    If you’d prefer not to have the viability scan, please allow a couple of days after the 10-week mark to avoid repeat appointments for drawing the bloods. You can also miss all the advantages of the 10-week scan, because your baby will be too young to have a proper early anomaly scan. 

    In theory, NIPT is available from 9-40 weeks, but it is strongly recommended to take the test in the first trimester, as the pregnancy management options in the second trimester can be very limited. 

    Can I do NIPT at 9 weeks?

    Yes, you can. Panorama AI works from 9 weeks. Please note that in this case, structural assessment of the baby by ultrasound can be limited and we will be unable to screen for some very serious conditions like holoprosencephaly or spina bifida. If you wish to have NIPT before 10 weeks, please consider a scan from 9 weeks 4 days.

    How are the NIPT results communicated?

    Following your ultrasound scan appointment, you will receive a detail scan report from our doctors, as a hard copy and a PDF version sent to you via our secure cloud system Tricefy.

    As soon as we receive your NIPT test results from the laboratory, our clinician reviews the test results and signs them off. One of our friendly clinical staff will then contact you via a phone call to interpret the test results. We will then send you a soft copy of the test results via Tricefy.

    Who is NOT eligible for a non-invasive prenatal screening (NIPT)?

    The majority of NIPT are  NOT validated and cannot be used in pregnancies with:

    • a history of or active malignancy
    • a pregnancy with triplets, quadruplets or higher order
    • a history of bone marrow or organ transplants
    • mosaicism for the parents
    • maternal aneuploidy (chromosomal abnormality)
    • in women under the age of 18

    Please note that IVF pregnancies are eligible for a NIPT

    What is the processing time for the NIPT blood test?

    Turnaround time of the harmony test in London is about 3-5 working days in 95% of the cases. For panorama, the tests are sent over to the US and can take up to 5-9 working days.

    From our clinic the sample is securely collected by a specialist medical courier service.

    See the below information about the harmony test no-call results and redrawing the blood sample (no additional cost.)

    What are the advantages of NIPT?

    The main advantages of NIPT are related to Down’s syndrome (T21) screening.

    They are:

    • early testing from 10 weeks
    • high negative predictive value for T21
    • high detection rate for T21
    • low false-positive rate for T21
    What are the limitations of NIPT?

    As any screening test NIPT has some disadvantages.

    Here there are the most significant NIPT limitations:

    • relative high cost of the cfDNA test (Harmony Test)
    • whilst a very sensitive screening test, it is not diagnostic
    • cannot detect ANY physical (structural) anomaly
    • very limited effectiveness for the babies that have increased nuchal translucency (NT) thickness or physical (structural) anomaly
    • processing time of up to a week (or longer in 5% of the cases) or even 10 days for Invitae NIPS
    • failure to return a result in up to 5% of women (‘no-call’ results) which is more common for Harmony Test
    I have never heard about PrenatalSafe NIPT, should I choose it?

    Currently, we consider PrenatalSafe as the best option for NIPT in London, because it provides advanced technology, low no-call results, and a short turnaround time (the lab is UK based). PrenatalSafe can be considered the best replacement for the outdated Harmony Test.


    • advanced technology
    • reliable screening for Down’s syndrome
    • uses a small amount of maternal blood
    • short turnaround time
    • low no-call rates
    • works for vanishing twin syndrome
    • highly reputable in Europe


    • Limited experience using the test in London
    I have never heard about Panorama NIPT, should I choose it?

    The main advantages of the brand-new panorama AI algorithm comparing with other NIPT providers are:

    • £200 test cost. This transparent price solution makes our combination of expert ultrasound scan and NIPT to be the most advanced and cost-effective option for early reassurance of the parents
    • Fewer no-call results (1.4%) than other NIPT providers
    • Low fetal fraction cull-off (only 2.8%)
    • Extended diagnostic panel: option to screen for Di George Syndrome ( 22q del), Turner syndrome, triploidy and other conditions for an additional fee. 

     The main disadvantages of Panorama Test are:

    • Longer turnaround time of 7-10 working days because of blood sample transfer to North America-based Natera Laboratory.
    • Higher chance for false-positive and inconclusive results.
    What if my NIPT results show high chance for a chromosomal anomaly?

    In case the NIPT result shows a high chance for Down syndrome or other conditions, our doctor will contact you and explain the further steps we advise to take. We will most likely arrange a referral to your NHS fetal medicine unit for further counselling and possible diagnostic test such as CVS or amniocentesis.

    Alternatively, we can refer you to a private fetal medicine consultant (consultation cost is not included in our service).

    We will also offer early fetal echocardiography for free (regular cost of the examination £320) for all our patients with high chance NIPT for trisomy 21, Di George syndrome, trisomy 18, trisomy 13 and Turner syndrome.

    What are the reasons for NIPT false positive results?

    Although our NIPT options are very accurate, some positive high chance for Downs syndrome results are false and the baby does not in fact have trisomy 21.

    Biological factors with the potential to cause discordance between cfDNA results and the baby’s genetic status include uncommon conditions like confined placental mosaicism, fetal mosaicism, maternal chromosome changes, and the presence of an unrecognised, nonviable (or viable) twin.

    What do NIPT no-call results mean?

    Most pregnant women receive complete results from cfDNA testing, indicating either a high or low probability for aneuploidy.

    In about 3% of cases (much more common with a harmony test) we will need to contact you without giving you a test result and ask you to come in for an additional sample of blood or to give us more information about your pregnancy or medical history. There will be no extra cost for an additional mother’s blood test.

    It is because in small proportion of blood specimens submitted after 10 weeks gestation there is an insufficient amount of the baby’s cfDNA. This situation is called low fetal fraction. The chance to have low fetal fraction is getting higher with increased maternal body weight. There are other rare factors making NITP results inconclusive.

    In the case of a harmony test no-call result, we will discuss options of alternative screening and/or referral for diagnostic testing if you either decline a second attempt at NIPT or do not receive a result after two attempts.

    Our NIPT Refund Policy

    The harmony scan can only be done from a gestational age of 10 weeks, while panorama NIPT can be done from 9 weeks. TDL/Natera do not accept any blood samples for patients below that gestational age. We recommend waiting until a gestational age of 10 weeks + 2 days (9+4 for panorama) to perform the harmony/panorama scan to avoid having to come in more than once.

    In case you booked for a panorama/harmony scan, but the ultrasound scan indicated a GA below 9/10 weeks (respectively), we will have to rearrange for you to come in at a later date for an additional cost of £50 to cover for our staffing cost.

    In the case of no-call results from the test (about 3% of the cases), we will be happy to schedule in another time to draw another blood sample free of charge. In case of a second no-call result, we will refund the harmony test portion of the appointment charge as per below. If, upon discussion with our clinician, you decide that the harmony test is not the right decision for you, we will refund the harmony test proportion of the appointment and will only charge for the scan.

    In the case of inconclusive results for Downs syndrome or trisomies 18 or 13, we are committed to refunding the harmony test cost.

    Because the harmony test is being undertaken by a third party, TDL (The Doctors Laboratory), we will contact them to arrange the refund. The refund will be for the harmony test only (we cannot compensate the cost of ultrasound) and will be processed in a few business days.

    There is no reimbursement for inconclusive fetal sex results. In those rare cases we will offer you an anatomy and gender scan for a reduced cost and will discuss the findings and need for further referrals.

    Should I delay the NIPT for 12-14 weeks and perform it after my NHS NT Scan?

    No, we think it is outdated approach and the best way is to perform both the 10 week anomaly scan and NIPT at 9-10-11 weeks. The benefit of this approach is that the tests are performed as early as technically possible.

    Understandably it will be impossible to visualise some fetal structures and organs at 10 weeks and some structural anomalies will be undiagnosed at this very early stage. Keeping this in mind, we recommend performing our early fetal scan at 15-16 weeks for further reassurance and exclusion of majority severe structural anomalies.

    Learn more about our early pregnancy scans.

    I have a pregnancy with a vanishing twin, can I do NIPT?

    Vanishing twin is a situation with twin pregnancies when the embryo or fetus in one of the sacs fails to develop or dies at the early stages of pregnancy. Interpretation of NIPT in the case of a vanishing twin phenomenon is complicated due to contamination of the sample by DNA of a non-developing twin pregnancy.

    Our advanced NIPTs: PrenatalSafe and UNITY can be used in this situation.

    Delaying the NIPT by five weeks is a recommended approach to reduce the chances of false-positive results associated with the vanishing twin syndrome.

    Do you want to know more about your options of NIPT?

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