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Basic vs Extended NIPT

Basic vs Extended NIPT explained London Pregnancy Clinic.

Choosing the Best NIPT Clinic in London: A Comprehensive Guide for Expectant Parents

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Non-invasive prenatal testing (NIPT) has revolutionised prenatal screening by providing expectant parents with a highly accurate and safe method of detecting genetic conditions in the fetus. However, not all NIPTs are created equal. Understanding the difference between basic and extended NIPT is crucial for making informed decisions during pregnancy. In this article, we will explore the key distinctions between these two types of NIPT and the implications they have for prenatal care.

What is Basic NIPT?

Basic NIPT focuses primarily on detecting common chromosomal aneuploidies. These include:

  1. Trisomy 21 (Down syndrome): The most frequently occurring aneuploidy, characterised by an extra copy of chromosome 21. This condition is associated with a spectrum of developmental delays, intellectual disabilities, and physical features such as hypotonia, a flat facial profile, and a single palmar crease.
  2. Trisomy 18 (Edwards syndrome): Associated with severe developmental delays and physical abnormalities.
  3. Trisomy 13 (Patau syndrome): A rare but severe condition linked to profound developmental issues.
  4. Many basic NIPTs include sex chromosome aneuploidies, conditions that affect the number of X or Y chromosomes, such as Turner syndrome (45,X) and Klinefelter syndrome (47,XXY).

Basic NIPT typically provides results with high sensitivity and specificity for these conditions. Among the conditions tested, NIPT has the highest sensitivity and specificity for trisomy 21, and its diagnostic performance is lower for trisomy 18 and trisomy 13. However, sex chromosome aneuploidies are known to have a relatively low positive predictive value (PPV), which means they may result in a high false positive rate.

What is Extended NIPT?

Extended NIPT goes beyond the common aneuploidies to screen for additional genetic conditions. This comprehensive approach includes three distinct levels of genetic screening:

Aneuploidies

As with basic NIPT, extended screening includes common trisomies (Down, Edwards, and Patau syndromes) and sex chromosome aneuploidies, but it also assesses rarer autosomal aneuploidies affecting other chromosomes. Importantly, checking for additional syndromes does not compromise the performance of the test for trisomy 21 (Down syndrome).

Microdeletions

Microdeletions are variants of structural chromosomal anomalies. They involve the loss of small but critical segments of DNA within a chromosome. These missing segments can contain multiple important genes, leading to severe and sometimes life-altering conditions. Some microdeletions are more severe than Down syndrome (trisomy 21). Examples of microdeletion syndromes are:

  • 22q11.2 deletion syndrome (DiGeorge syndrome): Associated with heart defects, immune dysfunction, and developmental delays.
  • Cri-du-chat syndrome: Caused by a deletion on chromosome 5, leading to intellectual disability and distinctive physical features.
  • Prader-Willi and Angelman syndromes: Resulting from deletions on chromosome 15, with unique clinical presentations.

Single-Gene Disorders (monogenic syndromes)

Most genetic syndromes in children are related to monogenic (single-gene) disorders. These tests screen for mutations in individual genes that may cause de novo or hereditary conditions. Many of these single-gene disorders can be associated with physical and/or intellectual disabilities. Examples include:

  • Achondroplasia: A de novo mutation resulting in a common form of dwarfism.
  • Apert syndrome: A genetic condition characterised by craniosynostosis (premature fusion of skull bones), distinctive facial features, and fusion of fingers, often leading to functional and aesthetic challenges.
  • Noonan syndrome: A condition with features like heart defects, developmental delays, and distinct facial characteristics.
  • Cystic fibrosis: A hereditary condition affecting the respiratory and digestive systems.

Benefits of Extended NIPT

Extended NIPT provides a more detailed assessment of the fetus’s genetic health. It is particularly advantageous in the following scenarios:

  • High-risk pregnancies: For parents with a family history of genetic conditions, prior pregnancies affected by genetic disorders, advanced maternal and/or paternal age, or IVF pregnancies, extended screening can offer invaluable insights.
  • Unexplained ultrasound findings: When ultrasound findings or abnormalities suggest a potential genetic condition, extended NIPT can help clarify the diagnosis.
  • In cases of increased nuchal translucency (high NT), when parents prefer to avoid invasive diagnostic tests such as CVS or amniocentesis and opt for NIPT, it is essential to consider the limitations of basic NIPT. Basic NIPT does not screen for many genetic syndromes associated with increased NT. In such situations, extended NIPT can be a preferred option, as it includes screening for monogenic conditions like Noonan syndrome, Kabuki syndrome, severe skeletal dysplasias, and other syndromes, as well as microdeletions such as 22q11.2 deletion syndrome (DiGeorge syndrome).
  • An additional test after normal CVS or amniocentesis results for common trisomies (Down, Edwards, and Patau syndromes) and microdeletions/microduplications is often recommended. Unfortunately, for many parents, the standard invasive diagnostic test does not check for most genetic syndromes. To check for monogenic syndromes (single gene disorders), someone needs to have a test called exome or whole genome sequencing (WGS). Extended NIPT, looking for selected monogenic syndromes, will have an additional value in those cases. It cannot replace the exome but will screen for common and serious monogenic conditions.
  • Reproductive planning: Knowledge of single-gene disorders or microdeletions can inform reproductive decisions, such as choosing between continuing or terminating a pregnancy, planning for specialised care or interventions post-birth, and understanding the likelihood of recurrence in future pregnancies. This information also helps families prepare emotionally and financially for potential medical needs after birth.

Choosing Between Basic and Extended NIPT

While extended NIPT offers a broader scope of screening, it also comes with additional considerations:

  1. Cost: Extended NIPT is typically more expensive than basic NIPT, which may influence accessibility.
  2. Time-Consuming: Because of the complexity of the tests, some of the extended NIPTs can have much longer turnaround time.
  3. False Positives: Screening for microdeletions and sex chromosome aneuploidies may yield higher rates of false positives compared to basic NIPT, necessitating confirmatory diagnostic tests such as amniocentesis or chorionic villus sampling (CVS). Among the various conditions tested, extended NIPT shows the poorest performance for these two categories due to different biological and technical challenges.
  4. False-Negatives: All NIPTs are screening tests and can have false-negative results due to technological limitations and biological reasons. Many genetic conditions are associated with multiple genes, and these tests are designed to detect only known and relatively common pathogenic mutations, leaving rarer or unknown variants undetected.
  5. There is a small possibility of identifying a pathogenic single-gene variant (mutation) inherited from a parent. For example, a parent may carry a mild or subclinical form of a genetic disorder without being aware of it. Thorough genetic counselling is essential in such cases to evaluate the potential impact of this variant on the unborn child and to provide tailored advice for the family.
  6. Counselling Needs: The complexity of results from extended NIPT often requires detailed genetic counselling to help families understand the findings and their implications.
  7. Only highly advanced genomic laboratories can develop extended NIPT tests capable of detecting monogenic conditions and microdeletions. While these branded extended NIPTs are extensively evaluated and validated internally, they still lack independent validation. It is essential to mention that even basic NIPTs, such as the widely used TDL NIPT in London, have not been validated by external organisations, leaving the actual performance of these tests uncertain.

Genetic Labs and Their Brands of Extended NIPT

Fulgent Genetics (US), an accredited leader in clinical diagnostic genetic sequencing, provides the KNOVA test, which screens for a wide range of single-gene disorders and chromosomal anomalies. KNOVA features a meticulously curated panel of de novo genetic conditions designed to optimise diagnostic performance while minimising false-positive rates. Currently, KNOVA is regarded as one of the best choices for extended NIPT panels in the UK. At London Pregnancy Clinic we offer it as part of out state-of-the-art SMART Test NIPT screening method.

Natera’s (US) Panorama test, which includes screening for microdeletions, and the separate Vistara test, focuses on single-gene disorders. Natera was a pioneer in the development of extended NIPT; however, other companies now offer more comprehensive screening panels. Notably, the Panorama test for 22q11.2 deletion syndrome is the only extended NIPT validated by an independent study, demonstrating a detection rate of approximately 80% and a positive predictive value of about 50%.

Eurofins Genoma (Italy) offers the PrenatalSafe Complete Plus test, which screens for all aneuploidies, microdeletions, and selected monogenic disorders. A unique feature of this test is its ability to screen for cystic fibrosis and its applicability in cases of vanishing twin syndrome. However, PrenatalSafe Complete Plus has a limited monogenic disorders panel, a very long turnaround time, and is relatively expensive.

BGI Genomics (China) features the NIFTY Mono test, specialising in detecting monogenic conditions and other genetic anomalies. Nifty Mono offers probably the most comprehensive panel, screening for hundreds of chromosomal and genetic disorders. However, there are significant concerns regarding the use of patient data by BGI. In 2023, a group of MPs and peers in the UK submitted a letter to the Information Commissioner’s Office, requesting an investigation into privacy concerns surrounding BGI Group, particularly its NIFTY prenatal tests.

BillionToOne (US) offers the UNITY test, which uniquely combines carrier screening with fetal screening. UNITY screens for inherited single-gene disorders such as cystic fibrosis, sickle cell anaemia, and thalassemias, providing detailed insights into both parental and fetal genetic health. Notably, the UNITY and KNOVA panels are complementary, enabling enhanced diagnostic performance when used together. 

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Final Thoughts.

Choosing between basic and extended NIPT depends on individual circumstances, risk factors, and the level of detail desired in genetic screening. While basic NIPT provides robust detection of common aneuploidies, extended NIPT offers a deeper dive into genetic health by screening for microdeletions and single-gene disorders. It is anticipated that future developments in extended NIPT panels will increasingly focus on screening for monogenic (single-gene) disorders, given their clinical significance and the growing demand for more comprehensive prenatal testing options. Consulting with healthcare professionals and genetic counsellors can help families navigate these choices and ensure the best possible care for both the expectant mother and her baby.

When choosing a clinic for your NIPT, ensure they use advanced high-resolution ultrasound technology for the pre-test scan. High-quality imaging allows for a more accurate assessment of fetal health, which is crucial, particularly in the early stages of pregnancy (10-11 weeks). Avoid clinics with outdated or low-resolution scanners, as this can compromise the accuracy of the scan and potentially impact the performance of your NIPT.

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Genetic Counselling Services Launch

London Pregnancy Clinic genetic counselling services launch. Minimalist design symbolising carrier testing before conception, featuring a couple holding hands, a DNA strand, medical symbols, and a blooming flower with a calm and hopeful colour palette in soft pastels

Genetic Counselling Services Launch

Discover the importance of Genetic Counselling before and during pregnancy.

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London Pregnancy Clinic proudly announces the launch of our new genetic counselling services. These services focus on reproductive genetic carrier screening. Our goal is to provide vital information to individuals and couples about their genetic risks. This information helps them make informed reproductive decisions aligned with their values and beliefs.

  • London Pregnancy Clinic Team - Private registered genetic counsellor - Ailidh Watson - Experienced Women's Health Specialists in City of London

  • We are excited to introduce genetic counselling services at London Pregnancy Clinic. These services aim to help prospective parents understand their genetic risks. Genetic counselling is crucial in modern prenatal care. It offers both pre-test and post-test support, guiding you through complex genetic information.

    Additionally, we are delighted to welcome Ms Ailidh Watson, our new genetic counselling specialist, to our team. Ailidh brings a wealth of experience and expertise in genetic counselling, particularly in prenatal care and patients with cleft lip and/or palate.

Genetic Testing We offer

At London Pregnancy Clinic, we offer a range of advanced genetic tests. These tests provide crucial information about your reproductive health. Here are the key tests we provide:

SMART Test: Our SMART Test NIPT is the most advanced non-invasive prenatal test and scan package in the world. This signature test gives parents detailed knowledge about their baby’s health without the risks of invasive testing. We offer two genetic packages: SMART Test KNOVA, performed by the leading US lab Fulgent, and SMART Test Genoma, performed by the top European lab Eurofins. Genetic counselling before the SMART test is essential to understand its advantages and limitations, ensuring you make an informed decision about your baby’s health.

Basic NIPT: The Basic NIPT is another non-invasive prenatal test we offer. It focuses on detecting the most common chromosomal abnormalities, including Down syndrome. Like the NIPT Smart Test, it uses a simple blood draw from the mother. This test is an excellent option for those seeking essential genetic information. With its high accuracy, it ensures peace of mind during pregnancy.

Carrier Screening: Our comprehensive carrier screenings identify if you or your partner are carriers of specific genetic disorders. This test covers a wide range of conditions, including cystic fibrosis and spinal muscular atrophy. Knowing your carrier status helps in planning for a healthy pregnancy. It allows you to explore reproductive options like IVF with preimplantation genetic testing (PGT). Moreover, carrier screening informs family members about potential genetic risks.

It’s important to distinguish between Non-Invasive Prenatal Testing (NIPT) and carrier screening:

  • NIPT: Performed during pregnancy, typically between 10-20 weeks. It screens the fetus’s DNA for chromosomal abnormalities like Down syndrome.
  • Carrier Screening: Tests the parents’ DNA for specific gene mutations that could be passed to their child. It can be done before or during pregnancy.

Benefits of Genetic Testing

Genetic testing offers several advantages, not just for you but for your entire family. Here are some key benefits:

Understanding Health Risks: Genetic testing identifies if you or your partner carry genes for specific genetic conditions. This understanding helps assess the risk of passing these conditions to your children.

Informed Decisions: Knowing your genetic risks allows you to make informed choices about pregnancy and family planning. You can consider options like IVF with preimplantation genetic testing (PGT-M), early interventions, or other preventive measures.

Personalised Care: With detailed genetic information, doctors can provide more personalised care. They can recommend specific tests, treatments, or lifestyle changes to help manage or reduce health risks.

Family Health Insights: Genetic testing reveals crucial health information that may affect other family members. If a genetic condition is identified, relatives can also get tested and take steps to manage their health.

Early Intervention: Detecting genetic conditions early leads to timely interventions and better management. This approach improves the quality of life for affected individuals.

Peace of Mind: For many, genetic testing provides peace of mind. Knowing your genetic information can alleviate uncertainties about potential health risks.

Preventive Measures: Genetic testing enables preventive measures, potentially reducing the risk of having a child with a genetic syndrome.

Overall, genetic testing empowers you with knowledge about your health and your family’s health. It helps you make well-informed decisions and take proactive steps. This ensures the best possible outcomes for you and your loved ones.

Impact on Family Planning?

Our carrier screening tests identify carriers of specific genetic disorders. Even without symptoms, you might still be a carrier. This knowledge is crucial for informed family planning. Knowing your carrier status can significantly influence family planning decisions. Couples who are both carriers face a 25% risk of having an affected child. This information empowers them to explore various reproductive options, such as:

  • Using donor gametes to conceive.
  • Pursuing in vitro fertilisation (IVF) with preimplantation genetic testing (PGT).
  • Accepting the risk and preparing for a potentially affected child.
  • Considering adoption or remaining childless.

Carrier results can also influence the timing of pregnancy, prenatal testing decisions, early intervention for certain conditions, and emotional preparedness. Carrier screening identifies carriers for many genetic conditions, including:

  • Cystic Fibrosis
  • Spinal Muscular Atrophy (SMA)
  • Sickle Cell Disease
  • Tay-Sachs Disease
  • Fragile X Syndrome
  • Duchenne Muscular Dystrophy

Other conditions include Thalassemias (alpha and beta), Familial Dysautonomia, Fanconi Anemia, Gaucher Disease, and Niemann-Pick Disease.

Importance of Genetic counselling

Genetic counselling is vital in the carrier screening process. Our certified clinical genetic counsellors are dedicated to supporting you through every step. Here’s how:

Educating the Public and Healthcare Professionals: We provide standardised education about genetic carrier screening. This knowledge empowers you and your healthcare providers with essential information.

Pre-Test Counselling: Before testing, we outline the screening process and potential outcomes. This preparation ensures you are fully informed and ready.

Post-Test Counselling: After testing, we interpret your results and discuss your options. This support helps you understand your situation and make informed decisions about your reproductive health.

Collaborating with Healthcare Providers: Our counsellors work with other healthcare providers to ensure comprehensive care in complex cases. This collaboration enhances your overall care experience.

In summary, London Pregnancy Clinic’s genetic testing and genetic counselling services offer comprehensive support and essential information. These services empower you to make informed decisions and take proactive steps for your family’s health. For more information or to schedule a test, please visit our website or contact us directly. Our team is here to support you in planning a healthy future for your family.

Ethical and Emotional Support:

Genetic counselling provides ethical guidance and emotional support. Our genetic counsellors help individuals and families navigate complex genetic information. Here’s how we assist:

  • Risk Assessment: We evaluate your risk based on family history, ethnic background, and genetic test results. This assessment is crucial for understanding potential health risks.
  • Informed Decision-Making: Knowing your genetic risks allows you to make informed choices about genetic testing and reproductive options. This empowers you to take control of your health and family planning.
  • Explaining Test Results: We interpret your genetic test results and explain their implications. This helps you understand what the results mean for you and your family.
  • Emotional Support: We offer emotional support and coping strategies. Understanding genetic risks can be challenging, and our counsellors are here to help you navigate these emotions.
  • Personalised Healthcare Recommendations: Based on your genetic profile, we provide personalised healthcare recommendations. This ensures you receive care tailored to your specific needs.

We are excited to welcome Ms Ailidh Watson to our team as our genetic counselling specialist. Ailidh is a registered private genetic counsellor with a broad range of experience. She has specialist interests in prenatal care and patients with cleft lip and/or palate. Her qualifications include a BSc (Hons) in Genetics from the University of Glasgow and an MSc in Genomic Counselling from the University of Manchester, where she graduated with distinction.

Ailidh’s credentials also include the Skilled Helper Course and registrations with AHCS and HCPC. Her services at LPC include genetic counselling, carrier screening, NIPT counselling, and prenatal screening, including NIPT. Ailidh will be your go-to person for all things genetic counselling.

Final Thoughts

London Pregnancy Clinic’s genetic counselling services represent a comprehensive approach to reproductive health. These services combine advanced genetic testing with expert counselling tailored to individual needs. They empower couples with the knowledge to make informed reproductive choices aligned with their values and circumstances.

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Understanding NT’s 95th Percentile

Graphic of understanding NT's 95th Percentile. A baby on a timeline with abstract representations of measuring tools.

Understanding NT’s 95th Percentile:

Nuchal Translucency (NT) Thickness Measurements in the 1st Trimester and What to Do if NT is Increased?

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Nuchal Translucency (NT), developed over 30 years ago in the early 1990s, remains a pivotal screening marker for evaluating early fetal well-being. Widely used, it screens for chromosomal and genetic conditions, as well as heart defects and other structural anomalies in the developing fetus. To get an understanding of NT’s 95th percentile we will discuss the importance of NT measurements, variations in cutoff values, and what to do if your baby’s NT measurement falls above the 95th centile but below the 3.5mm threshold.

The Significance of Nuchal Translucency Measurements:

NT refers to measuring the clear fluid space at the back of the baby’s neck during an ultrasound scan. According to NHS guidelines, it is measured between the 11th and 14th weeks of gestation. Presently, it is a cornerstone of the NHS Chromosomal Syndromes Screening Program conducted through Combined Screening Testing (CST). This program relies on the enduring significance of NT to assess the risk of chromosomal syndromes in the first trimester of pregnancy. Elevated NT measurements can indicate potential chromosomal abnormalities such as trisomy 21 (Down syndrome) and genetic conditions like Noonan syndrome, as well as heart defects and other structural anomalies. However, there is a significant level of uncertainty regarding what constitutes an abnormal NT measurement.

Variations in Cutoff Values:

One of the challenges with NT measurements is determining what constitutes an abnormal measurement. There is considerable variation in the cutoff values used by different research papers and guidelines. The majority of research studies and international society guidelines use the 95th centile as the threshold for abnormal NT measurements. This means that if your baby’s NT measurement falls below the 95th centile, it is considered normal. However, the NHS guidelines use a more conservative cutoff of 3.5mm. This 3.5mm cutoff is equivalent to the 99th percentile, representing a higher threshold for what is considered abnormal by NHS.

The Importance of Gestational Age:

It’s crucial to understand that the 95th centile for NT measurements varies with gestational age. Younger fetuses at 11 weeks tend to have naturally smaller NT measurements compared to those closer to 14 weeks. Therefore, determining whether your baby’s NT measurement is normal or not depends on both the absolute measurement and the gestational age.

Understanding NT’s 95th Percentile Measurements:

We understand that expectant parents might find it challenging to locate validated data concerning the 95th centile cutoff for their baby, as such data is not readily accessible online. To provide support, we have developed an NT thickness reference table based on highly esteemed international data from the study conducted by Wright et al in 20081. Additionally, we have cross-referenced data on normal NT measurements for the 10-11-week gestational period from Grande et al.’s publication in 20142, which closely aligns with Wright’s findings. Consequently, we have assembled a table that delineates the limit of an increased NT (95 centile) for each week from the 10th to the 14th week, utilising gestational age data recommended by the British Medical Ultrasound Society (2009)3.


Gestational Weeks 10+0 10+1 10+2 10+3 10+4 10+5 10+6 11+0 11+1 11+2 11+3 11+4 11+5 11+6 12+0 12+1 12+2 12+3 12+4 12+5 12+6 13+0 13+1 13+2 13+3 13+4 13+5 13+6 14+0 14+1
NT 95th centile mm 2.3 2.3 2.4 2.4 2.4 2.4 2.3 2.2 2.2 2.2 2.2 2.2 2.2 2.2 2.3 2.3 2.4 2.4 2.5 2.6 2.6 2.7 2.7 2.7 2.8 2.8 2.8 2.8 2.8 2.8

Our chart represents the distribution of increased NT measurements (> 95th centile) in relation to the gestational age. It’s important to note that, at every stage of gestation, normal NT measurements remain below 2.8 mm. Therefore, any NT measurement equal to or greater than 2.8 mm is considered elevated.

What occurs when there is a significant elevation in NT measurements? 

If NT thickness is 3.5mm or more (>99th centile) you will be referred to the fetal medicine unit (FMU) of your NHS hospital or FMU of a large regional NHS trust, where doctors will scan your baby to exclude structural anomalies associated with increased NT and offer further tests (CVS or NIPT). They will also offer fetal echocardiography at 16-20 weeks to exclude associated CHD.

What to Do if NT Measurement is Above the 95th Centile but Below 3.5mm (99th centile)?

The NHS adopts a conservative approach and does not acknowledge the 95th centile raised NT cutoff. Consequently, additional scans and tests are not scheduled for these babies before the routine 20-week anomaly scan conducted by the NHS. However, when the NT measurement surpasses the 95th percentile, it is advisable to proceed with further testing. In such instances, considering Non-invasive Prenatal Testing (NIPT) and an Early Fetal Anomaly Scan (Early Fetal Scan) are recommended.

SMART TEST – A Comprehensive Screening Option

For babies with elevated NT (between 95-99th centile), we have introduced the SMART TEST, which stands as the most advanced early reassurance package available. It comprises two expert early anomaly scans, Early Fetal Echocardiography, and the most comprehensive state-of-the-art NIPT panel. The SMART TEST can effectively rule out the majority of severe congenital heart defects (CHDs) and other structural anomalies associated with elevated NT, and reduce the probability of your baby being affected by chromosomal, genetic, or structural abnormalities.

While the SMART TEST is expensive, it is the most comprehensive early reassurance package available in the UK. For parents unable to afford the SMART TEST, there is a more affordable option of the Early Fetal Scan and an extended Panorama Test. The Early Fetal Scan screens for CHDs, but does not include a detailed examination of the fetal heart. You can further upgrade the scan and Panorama Test NIPT package to include eECHO.

If you have received concerning news about your baby’s increased nuchal translucency, we strongly recommend discussing the SMART TEST with one of our specialists.

Conclusion

Nuchal translucency measurements play a crucial role in assessing fetal well-being during the first trimester of pregnancy. Understanding the variations in cutoff values, gestational age, and available screening options is essential for making informed decisions if your baby’s NT measurement falls above the 95th centile but below the 3.5mm NHS threshold (99th centile). The SMART TEST, with its comprehensive NIPT panel and early fetal echocardiography, offers a valuable non-invasive screening option for parents seeking more information about their baby’s health. We are committed to offering you the best possible care, and you are always welcome to have a personal consultation with us to decide on the most suitable approach based on your individual circumstances.

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Possibility of Early Spina Bifida Diagnosis from 10 Weeks.

Graphic of Early Spina Bifida Diagnosis. A baby that is getting its spine scanned at 10 weeks.

Spina Bifida Early Diagnosis from 10 Weeks of Pregnancy

DR Fred Ushakov Headshot. London Pregnancy Clinic Medical Director. Specialist in Fetal Medicine & Obstetrical Ultrasound.

An Interview with Dr. Fred Ushakov

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In honour of UK Spina Bifida Awareness Week, Dr. Ushakov, Founder and Managing Director of London Pregnancy Clinic, discusses the possibilities of early diagnosis of spina bifida. He is an internationally renowned expert in fetal medicine, with a primary focus on fetal spina bifida and is also currently affiliated with FMU UCLH. In recognition of UK Spina Bifida Awareness Week, we have had the privilege of asking Dr. Ushakov several vital questions about spina bifida.

Dr. Ushakov was interviewed by, our Specialist Sonographer in Fetal Medicine, Gynaecology & Fertility, Ms Shaz Khojasteh.

What sparked your interest in spina bifida?  

“In 1980, as a young obstetrician heavily involved in attending deliveries and particularly interested in ultrasound technology, I performed a scan on a young pregnant woman. I noticed something unusual about the baby’s brain, although I couldn’t quite discern the exact issue. Subsequently, I was present at her delivery, and to my surprise, the baby was born with spina bifida. This experience was truly shocking. It occurred over 35 years ago during the early stages of ultrasound technology when both knowledge and technology were limited.”

What actions did you take next?

“After that shocking experience, I became genuinely intrigued by effectively detecting spina bifida. I dedicated significant effort to mastering scanning techniques for identifying spina bifida in babies. Over time, I evolved into an expert in this field, with a particular focus on spotting it as early as 10 weeks into the pregnancy. And naturally, I made it a point to share this knowledge with my colleagues, advocating for early spina bifida detection.”

How many babies with spina bifida have you encountered?

“I’ve seen hundreds of fetuses with spina bifida during my career. It’s become a routine part of my work – conducting early scans to detect spina bifida and performing expert scans for babies already diagnosed with this condition. Spina bifida is actually relatively common. In the UK, it’s estimated that around 1 in every 1,000 pregnancies is affected by spina bifida. Even though it might not be as well-known as some other conditions, its effects on those who have it can be quite substantial. This is why early detection and awareness are so important.”

Why is spina bifida so important?

“Open spina bifida holds immense significance due to its prevalence as a major fetal structural defect. It adversely affects essential bodily functions, such as bowel and bladder control. Walking becomes a challenge for most babies born with open spina bifida, and some may also exhibit brain abnormalities. While treatments can enhance outcomes, a complete cure remains elusive. Many babies survive, but their lives are profoundly impacted by long-lasting disabilities. In essence, it’s a severe condition with enduring consequences.”

What do you consider the main issue with spina bifida?

“The primary concern regarding spina bifida, from my perspective, is the alarming lack of awareness. This lack of awareness extends not only to patients but also to primary healthcare providers. From my experience, many pregnant women take folic acid supplements without fully grasping their significance. It’s imperative to raise awareness and educate both the general public and healthcare professionals about this condition, its risk factors, and the crucial role of folic acid supplementation during pregnancy and early first-trimester spina bifida screening. Unlike the widely recognized Down’s syndrome, spina bifida remains relatively obscure. This is a significant concern because, for some babies with spina bifida, the potential outcomes can be even more challenging than those for Down’s syndrome.”

Fred, could you clarify why it’s essential to start taking folic acid immediately upon discovering pregnancy?

“Yes, immediate folic acid supplementation upon discovering pregnancy is of paramount importance. Neural tube formation is an early pregnancy event, usually concluding by the end of the 6th gestational week, approximately 28 days after conception. In babies with spina bifida, the neural tube fails to close correctly, leading to spinal cord and spine bone issues. This anomaly develops extremely early when the baby is less than 1 cm in size and has just initiated its heartbeat.

Folic acid plays a pivotal role during the critical period before and during the first six weeks of pregnancy when the baby’s spine is forming. In practical terms, most people discover their pregnancy around 4 weeks after conception, and by that point, they are already 4 weeks into the pregnancy. This leaves just two weeks during which folic acid can exert its most significant impact. Taking early action is the key to providing essential support for your baby’s neural tube development and minimizing the risk of spina bifida.”

Let’s delve into early Spina Bifida diagnosis during pregnancy. When can you identify this condition?

“With my level of expertise and the use of advanced 3D ultrasound scanners (Fig 1), I can diagnose the majority, probably over 90%, of open spina bifida as early as 10 weeks into the pregnancy. To put it differently, personally missing a diagnosis of spina bifida at that stage would be a great disappointment to me, and I would be highly motivated to conduct a thorough investigation into why such a diagnosis was missed. 

  • 3D Ultrasound GIF of baby at 10 week. Image by London Pregnancy Clinic - for educational purpose.

    Fig 1 – 3D ultrasound image of the baby at 10 weeks: All main structures are visible
  • It’s important to note that achieving a 100% accuracy rate in diagnosing spina bifida through ultrasound is a challenge. There can be significant variations in the presentation of spina bifida, and in some rare cases, the anomaly may go undiagnosed until delivery. While early detection is highly valuable, there are instances where the condition’s subtleties make it difficult to diagnose definitively with ultrasound.”

How can you diagnose spina bifida so early? Are you inspecting the baby’s spine?

“No, actually, it’s quite challenging to directly visualize spinal abnormalities at this early stage. What I’m primarily focused on is the fetal head and brain (Fig 2). In cases of open spina bifida, there’s a distinct phenomenon at play. There is a leakage of fluid from the brain through the hole in the spine, and this leakage creates a very specific brain anomaly known as Chiari 2 malformation. I’m essentially searching for the earliest evidence of this phenomenon in the ultrasound images. It’s a highly specific indicator – when this particular brain anomaly is present, it’s a strong indication that the baby has spina bifida.

Certainly, at 10 weeks, I also examine the fetal spine. The spine is not yet ossified, so it appears as dark lines running along the baby’s back, and often I can even discern individual vertebrae as bright dots (Fig 3). This level of detail means that very severe spinal deformities can be visible. Sometimes, spina bifida can manifest as a small bubble on the baby’s back at this early stage (Fig 4).”

  • Ultrasound GIF of baby's brain at 10 weeks. Image by London Pregnancy Clinic - for educational purpose.

    Fig 2 – Normal brain at 10 weeks: this baby has no spina bifida
  • Ultrasound GIF of baby's spine at 10 weeks. Image by London Pregnancy Clinic - for educational purpose.

    Fig 3 – Baby’s spine at 10 weeks: no deformities
  • Ultrasound GIF of baby with spina bifida at 11 weeks. Spina bifida cystica is seen at the bottom of the spine. Image by London Pregnancy Clinic - for educational purpose.

    Fig 4 – Baby with spina bifida at 10-11 weeks: spina bifida marked by the circle

Can other professionals detect spina bifida early?

“Yes, there are indeed many research studies indicating the possibility of early detection. One of the most significant research efforts comes from King’s College Hospital in London. Sonographers at this hospital have scanned over 100,000 babies at 11-13 weeks of pregnancy and were able to detect more than half of the fetuses with spina bifida. This achievement is truly impressive, although it’s important to note that it may not be applicable to all NHS trusts. King’s College Hospital has a dedicated unit, established protocols, and a comprehensive training program. Only a handful of other hospitals across the UK, including UCLH that I work for, have similar protocols in place.”

What is the situation like in an average NHS hospital?

“In NHS hospitals, there is a screening ultrasound program called the anomaly scan, which is typically conducted at 19-20 weeks into the pregnancy. During this scan, sonographers check for spina bifida among other anomalies.

Unfortunately, there isn’t a routine first-trimester screening for spina bifida, and the majority of cases are detected during the second trimester. In a 2019 survey of ultrasound units performing scans in the first trimester (11-13 weeks) in England, it was found that only 16% of them included a check of the fetal spine in their protocols.”

Tell us about the “crash sign” and its significance.

“Yes, indeed. Many research groups have proposed various methods for detecting spina bifida in the first trimester. In our case, we’ve come up with a marker that represents the ultrasound appearance of Chiari 2 malformation in the early fetal brain. It’s pretty obvious when you have a top-notch ultrasound scanner.

Now, why ‘CRASH’? We actually have a video up on YouTube that demonstrates it, and once you watch it, the name will make perfect sense.”

Any advice for patients seeking early spina bifida ruling out?

“If you’re keen to know early on, I’d suggest considering booking a 10 Week Scan with a professional having a special interest in this area. For those with previous pregnancies affected by spina bifida, arranging a 10 Week Scan at Fetal Medicine Unit at UCLH with a referral from your primary NHS care provider is an excellent choice. Alternatively, you can book a 10 Week Scan privately at London Pregnancy Clinic. At our clinic, we can combine this scan with non-invasive prenatal testing (NIPT). Please inform our admin staff about your worries, and we will arrange a proper scan for your baby.

If you prefer to stick with NHS services, ask your sonographer during the 11-13 weeks scan if they’re actively screening for spina bifida. Some hospitals in London may have established protocols for this. However, if your NHS provider doesn’t routinely check for spina bifida (which is the case for most hospitals), you might want to consider an early anomaly scan (Early Fetal Scan) at 13-16 weeks through a private provider. For those going the private scan route, it’s a good idea to check if the clinic screens for spina bifida at early stages. Advanced private ultrasound clinics are typically well-equipped, and their staff may have special training in fetal medicine.

Please note that the majority of sonographer-run clinics that provide NIPT or perform non-medical gender scans do not screen for spina bifida.”

It seems like you prefer screening for spina bifida at 10 weeks rather than at the time of the standard NHS scan around 12 weeks. Is that accurate, and could you tell us why?

“Yes, you’ve got it right. In the past, I used to advocate for spina bifida screening during the conventional nuchal translucency scan at around 12-13 weeks. But with the introduction of NIPT, which can be done as early as 10 weeks, I’ve started scanning for spina bifida even before the blood test. At 10 weeks, the little ones are really tiny, measuring less than 1.5 inches (around 35 mm).

Interestingly, with the help of state-of-the-art ultrasound technology (and we’re lucky to use the most advanced machines), many fetal structures are surprisingly easier to examine at 10 weeks compared to 12 weeks. The brain and spine, in particular, stand out as more visible structures.

I won’t bore you with all the technical stuff, but it’s somewhat paradoxical that I feel that an early screening at 10 weeks is actually probably more effective. Plus, it’s a relief for parents who are understandably anxious and want reassurance as soon as possible. But it’s essential to recognize that this type of screening demands a high level of expertise and top-notch ultrasound technology to be done effectively.”

Can other professionals detect spina bifida early?

“Yes, indeed. There are internationally renowned groups in Melbourne, Nice, and Berlin, among others, who also have experience in diagnosing spina bifida before the 11th week of pregnancy. At present, our joined expertise is largely based on anecdotal cases. This is because the incidence of spina bifida is relatively rare, occurring at a rate of 1 in 1,000 pregnancies. To establish statistically significant numbers and determine the detection rate of a 10-week scan, one would need to scan thousands and thousands of babies.”

What is the SMART TEST, and does it include screening for spina bifida?

“The SMART TEST is an innovative concept in prenatal care developed and offered by the London Pregnancy Clinic. It combines extended NIPT with expert ultrasound. The SMART TEST is unique in that it covers a wide range of structural anomalies, chromosomal conditions, and genetic diseases, and it can do so as early as 10 weeks into the pregnancy.

A primary target of the SMART TEST is indeed the earliest possible screening for spina bifida. The test incorporates advanced 2D and 3D ultrasound technology to thoroughly examine the fetal brain and spine at a stage when the baby has just transitioned from an embryo to a fetus. This comprehensive approach ensures early detection and peace of mind for expectant parents.”

Why do you believe that early detection of spina bifida is so crucial? After all, the condition can be diagnosed by the NHS anomaly scan at 20 weeks.

“I’m a strong advocate for early detection of spina bifida, and let me explain why. Spina bifida is a highly serious structural anomaly associated with severe disabilities. While we’ve made significant progress with in-utero surgical treatments, it’s important to understand that these treatments don’t cure the condition.

Moreover, it’s essential to highlight the significance of the surgical aspect. At UCLH, I’m part of the Fetal Surgery for Spina Bifida team, which is led by Professor Jan Deprest, an internationally renowned expert in fetal surgery. Our centre is the sole one in the UK commissioned by the NHS to provide this cutting-edge treatment. In my role, I conduct scans on the baby before and after the surgery. I take great care to evaluate the spinal lesion, perform a thorough examination of the baby’s brain, and perform a comprehensive top-to-toe scan of the entire baby. I’ve had the privilege of scanning hundreds of babies with spina bifida before and after surgery, contributing to their care.

Performing surgery on a baby with spina bifida while they’re still in the mother’s womb is an incredible feat. This complex procedure requires a skilled international team of doctors and medical professionals from the UK and Belgium. The delicate balance of providing life-changing treatment for the baby while ensuring the safety of both the baby and the mother is a remarkable achievement in fetal medicine.

However, almost half of mothers are not eligible for this ground-breaking surgical treatment, often due to the severity of the baby’s condition or additional fetal problems. For these parents, making difficult decisions about the pregnancy becomes a reality, often after 20 weeks. Even for parents eligible for surgery, the journey is challenging. They go through numerous tests, counselling, and procedures in a short time, adding to the stress.

All of this can be alleviated with early diagnosis. Early detection provides parents with the time and information they need to make informed decisions. For the most severe cases of spina bifida that are not operable, early detection helps parents understand their options from the start of the pregnancy. That’s why I advocate for screening for spina bifida as early as 10 weeks or at least at 12 weeks.”

Fred, as a conclusion, what advice or suggestions would you like to offer to future parents?

“If you are in the planning stages of pregnancy, consider starting to take folic acid supplements. Folic acid is most effective when taken before conception and during the first few weeks of pregnancy when the baby’s spine is forming. This simple step can contribute to the healthy development of your baby and reduce the risk of spina bifida.

Additionally, I’d like to emphasize the importance of early screening for spina bifida, which can now be done as early as 10 weeks into the pregnancy. This can provide you with valuable information, peace of mind, and ample time to make informed decisions about your baby’s health. If you have concerns or a history of spina bifida in your family, consider the SMART TEST at the London Pregnancy Clinic. It’s a comprehensive approach that combines NIPT and advanced ultrasound technology to screen for a wide range of conditions, including spina bifida.

Remember that knowledge is power. Being informed and seeking early detection can make a significant difference in the journey of your pregnancy. Stay well-informed, ask questions, and don’t hesitate to seek expert guidance. Your baby’s health is our priority, and we are here to help you every step of the way.”

References

(1) Karim, J., Pandya, P., McHugh, A. and Papageorghiou, A.T. (2019). OC23.06: Significant variation in practice for first trimester anatomy assessment: results from a nationwide survey. Ultrasound in Obstetrics & Gynecology, 54(S1), pp.60–61.

(2) Ushakov, F., Sacco, A., Andreeva, E., Tudorache, S., Everett, T., David, A.L. and Pandya, P.P. (2019). Crash sign: new first-trimester sonographic marker of spina bifida. Ultrasound in obstetrics & gynecology : the official journal of the International Society of Ultrasound in Obstetrics and Gynecology, [online] 54(6), pp.740–745.

(3) University College London Hospitals NHS Foundation Trust. (n.d.). Management of Fetal Spina Bifida. [online] Available at: https://www.uclh.nhs.uk/patients-and-visitors/patient-information-pages/management-fetal-spina-bifida [Accessed 21 Oct. 2023].

(4) Syngelaki, A., Hammami, A., Bower, S., Zidere, V., Akolekar, R. and Nicolaides, K.H. (2019). Diagnosis of fetal non‐chromosomal abnormalities on routine ultrasound examination at 11–13 weeks’ gestation. Ultrasound in Obstetrics & Gynecology, 54(4), pp.468–476.

(5) Rolnik, D.L., Wertaschnigg, D., Benoit, B. and Meagher, S. (2020). Sonographic detection of fetal abnormalities before 11 weeks of gestation. Ultrasound in Obstetrics & Gynecology, 55(5), pp.565–574.

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