FISH-Prenatal Aneuploidy Detection (2) Test: Booking, Price, and Results
About FISH-Prenatal Aneuploidy Detection (2) Test: Booking, Price, and Results
| Field | Value |
|---|---|
| Also Known As | FISH prenatal aneuploidy screen, Prenatal FISH aneuploidy detection, Rapid Aneuploidy Detection (RAD) FISH |
| Sample Type | Amniotic fluid (amniocentesis), Chorionic Villus Sample (CVS), cord blood, or other clinically indicated prenatal samples |
| Fasting Required | No fasting required |
| Report Time | 3 Days |
| Recommended For | Pregnant women with high-risk pregnancies: maternal age 35 or older, abnormal ultrasound findings, abnormal screening results, or a family history of chromosomal disorders |
| Price | Starting at ₹3,000 |
What is a FISH-Prenatal Aneuploidy Detection (2) Test?
The FISH-prenatal aneuploidy detection (2) test is a specialised genetic test performed during pregnancy. It uses a laboratory technique called Fluorescence In Situ Hybridisation (FISH) to check whether the foetus has an abnormal number of chromosomes 13 and 21. The test is carried out on a prenatal sample, most commonly amniotic fluid or chorionic villus tissue. It is also known as the FISH prenatal aneuploidy screen or Rapid Aneuploidy Detection (RAD) FISH.
What Does a FISH-Prenatal Aneuploidy Detection (2) Test Measure?
This test uses fluorescent probes that attach to specific regions of chromosomes 13 and 21. By counting the number of chromosome copies in foetal cells, the laboratory can identify whether an abnormal number is present.
The two chromosomes assessed and their clinical significance are listed below.
| Chromosome | What it Checks For |
|---|---|
| Chromosome 13 | Abnormal copy numbers associated with Patau syndrome (trisomy 13), a serious condition affecting the brain, heart, and other organs |
| Chromosome 21 | Abnormal copy numbers associated with Down syndrome (trisomy 21), which causes developmental delays and other health differences |
Why is a FISH-Prenatal Aneuploidy Detection (2) Test Done?
This test is recommended when there is a clinical reason to investigate the risk of a chromosomal abnormality in the foetus. A doctor or genetic counsellor typically advises the test after reviewing screening results and pregnancy history.
Common Symptoms That May Require This Test
The FISH-prenatal aneuploidy detection (2) test procedure is recommended based on clinical indicators rather than symptoms. The following findings or circumstances typically lead to a referral.
- Maternal age of 35 years or older at the time of delivery
- Abnormal ultrasound findings, such as increased nuchal translucency or heart defects
- A positive or high-risk result from non-invasive prenatal screening (NIPT) or other antenatal screening
- A previous pregnancy affected by a chromosomal disorder
- A family history of chromosomal conditions
- Raised levels of specific markers on a first- or second-trimester blood screen
- Significant parental concern requiring a definitive chromosomal result
Conditions This Test Can Help Detect
The FISH-prenatal aneuploidy detection (2) test can help identify the following chromosomal conditions in the foetus.
- Down syndrome (trisomy 21): causes delays in physical and mental development, along with other health differences
- Patau syndrome (trisomy 13): characterised by brain malformations, craniofacial anomalies, congenital heart disease, and severe involvement of multiple organ systems
FISH-Prenatal Aneuploidy Detection (2) Test During Pregnancy
This test is a core part of the prenatal diagnostic workup for women identified as high risk during routine antenatal care. Up to 95% of chromosomal abnormalities diagnosed before birth involve aneuploidy of a small number of chromosomes, and this test targets two of the most clinically significant. It is typically carried out between weeks 15 and 20 of pregnancy when amniocentesis is used, or between weeks 10 and 13 if chorionic villus sampling (CVS) is performed.
How to Prepare and What to Expect
Sample collection for this test involves an invasive procedure performed by a trained doctor in a clinical setting. The guidance below applies to the most common collection method, amniocentesis, along with notes on CVS.
Do You Need to Fast?
No fasting is required before this test. You can eat and drink normally before attending the procedure.
Practical Tips Before Your Test
Preparation steps are important for your safety and to ensure the sample is collected successfully. Please keep the following points in mind before your appointment.
- Bring a detailed clinical history, including your symptoms, previous test results, and family history, as this is required for the test. The PNDT Consent Form and Form G must also be completed before the procedure.
- Tell your doctor about all medications you are currently taking, especially blood thinners or anticoagulants, as these may need to be paused.
- Inform your doctor of any allergies to medicines, latex, anaesthesia, or tape.
- In some cases, your doctor may advise you not to empty your bladder for a few hours before amniocentesis, as a full bladder can make the procedure easier.
- Arrange for a trusted adult to accompany you and drive you home after the procedure.
Step-by-Step Procedure
The sample may be collected by amniocentesis or by chorionic villus sampling (CVS), depending on your gestational age and clinical needs. Both procedures are described below.
Amniocentesis (Amniotic Fluid Collection)
- An ultrasound scan is performed first to confirm the position of the baby and placenta and to identify a safe area for the needle.
- The skin on your abdomen is cleaned with an antiseptic solution.
- A thin needle is guided through the abdomen into the uterus under continuous ultrasound guidance.
- A small quantity of amniotic fluid, which surrounds the baby, is withdrawn through the needle.
- The needle is removed, and the puncture site is checked. You will be monitored for up to an hour before you leave.
- The fluid sample is labelled, stored at 2 to 8 degrees Celsius, and sent to the laboratory for FISH-Prenatal Aneuploidy Detection (2) Test analysis.
Chorionic Villus Sampling (CVS)
- An ultrasound scan is performed to map the location of the placenta.
- Depending on the placenta's position, a small catheter is passed through the cervix, or a needle is inserted through the abdomen under ultrasound guidance.
- A tiny piece of chorionic villus tissue (approximately 30 mg) is collected from the placenta.
- The sample is placed in a sterile container and transported refrigerated (2 to 8 degrees Celsius) to the laboratory for FISH analysis.
Factors That Can Affect Accuracy
Several factors can influence the reliability of the test result. These include the following.
- Poor sample quality or an insufficient number of foetal cells in the sample
- Maternal cell contamination, where the mother's cells are analysed instead of the baby's
- Low-level mosaicism, where only a small proportion of cells carry the chromosomal change
- Delay or improper temperature maintenance during sample transport
- Laboratory conditions and the expertise of the testing team
Understanding Your FISH-Prenatal Aneuploidy Detection (2) Test Results
Your results will indicate how many copies of chromosomes 13 and 21 are present in the foetal cells examined. A qualified doctor or genetic counsellor will review the findings in the context of your full pregnancy history before advising next steps.
| Parameter | Normal Result | Abnormal Finding |
|---|---|---|
| Chromosome 13 | 2 copies per cell (disomy) | 3 copies may indicate Patau syndrome (trisomy 13) |
| Chromosome 21 | 2 copies per cell (disomy) | 3 copies may indicate Down syndrome (trisomy 21) |
These ranges are general guidelines. Your doctor will interpret your results based on your age, health history, and other factors. Always consult a qualified healthcare professional for personalised medical advice.
Results During Special Conditions
A few situations can affect how results are interpreted or what they can reliably detect.
- Low-level mosaicism, where only some cells carry the chromosomal abnormality, may not be detected by this test.
- The FISH method also does not identify structural chromosomal abnormalities or numerical changes in chromosomes other than those targeted by the probes. For this reason, the American College of Medical Genetics advises that irreversible clinical decisions should not be based on FISH results alone.
This test is intended to be used alongside full chromosome analysis or chromosomal microarray.
How to Maintain Healthy Levels
This test detects chromosomal conditions that are present from conception and are not influenced by lifestyle. The following general wellness tips are relevant during pregnancy.
- Attend all scheduled antenatal appointments and follow your doctor's guidance throughout the pregnancy.
- Maintain a balanced diet and stay well hydrated to support your overall health during this period.
- Discuss all test results and their implications with a qualified genetic counsellor, who can explain your options and provide appropriate support.
Lupin Diagnostics FISH-Prenatal Aneuploidy Detection (2) Test Price
The FISH-prenatal aneuploidy detection (2) test cost at Lupin Diagnostics starts at ₹3,000. This test requires a visit to a Lupin Diagnostics centre; home collection is not available, as the sample must be collected by a trained clinician in a suitable medical setting.
| City | Approximate Price (₹) |
|---|---|
| Mumbai | 3000 |
| Pune | 3000 |
| Bangalore | 3000 |
| Chennai | 3000 |
Prices are indicative and may vary by location. Please confirm the current price at the time of booking.
How to Book
The FISH-prenatal aneuploidy detection (2) test online booking process is straightforward. Follow the steps below to schedule your test.
- Select the test on the Lupin Diagnostics website.
- Choose your city and preferred centre location.
- Visit the centre at your scheduled time; your doctor will perform the sample collection procedure.
- Receive your report via email or WhatsApp within 3 days of sample receipt at the laboratory.
Frequently Asked Questions
This test checks whether the foetus has an abnormal number of chromosomes 13 or 21. An extra copy of chromosome 21 may indicate Down syndrome, while an extra copy of chromosome 13 may indicate Patau syndrome. It gives results quickly and with high sensitivity.
The sample is usually collected by amniocentesis, where a small amount of amniotic fluid is withdrawn from the uterus using a fine needle guided by ultrasound. In some cases, chorionic villus sampling (CVS) is used instead, where a small piece of placental tissue is taken. Both procedures are carried out by a trained doctor in a clinical setting.
Amniocentesis for this test is typically performed between weeks 15 and 20 of pregnancy. If CVS is used, it can be carried out earlier, usually between weeks 10 and 13. Your doctor will advise the most appropriate timing based on your individual situation.
The report is typically available within 3 days of the sample reaching the laboratory. FISH analysis can often deliver preliminary results within 24 to 48 hours, making it one of the faster options for prenatal chromosomal testing.
No. The FISH-prenatal aneuploidy detection (2) test covers only chromosomes 13 and 21. It does not detect structural chromosomal abnormalities, mosaicism, or changes in other chromosomes. It is intended to be used alongside full karyotyping or chromosomal microarray for a complete picture.
The PNDT (Pre-Conception and Pre-Natal Diagnostic Techniques) Consent Form and Form G must be completed before the test is carried out. A detailed clinical history, including symptoms, previous test results, and family history, is also required. Please bring all relevant documents to your appointment.
Amniocentesis carries a small risk of miscarriage, estimated at approximately 1 in 200 procedures. There is also a rare risk of infection, occurring in fewer than 1 in 1,000 cases. Your doctor will discuss these risks with you before the procedure and answer any questions you may have.
FISH-Prenatal Aneuploidy Detection (2) Test: Booking, Price, and Results
