Pregnancy can be a period of excitement, anticipation, and care. To help assure the mother and her baby are healthy, physicians recommend a series of screening tests. One of these tests, called the Quadruple Marker Test, is an important, simple blood test that provides a lot of information about your baby’s growth and risk factors for certain genetic conditions.
This test is one of the maternal screening tests that help detect potential abnormalities of chromosomes or the neural tube early. Let’s look into exactly what this test is, when it is done, and how to understand the results.
What is Quadruple Marker Test?
The quadruple marker test is a prenatal screening test that measures four specific substances in a pregnant woman’s blood to evaluate the risk of chromosomal abnormalities in the baby.
The quadruple marker test checks for:
- Alpha-fetoprotein (AFP) – produced by the baby’s liver
- Human chorionic gonadotropin (hCG) – made by the placenta
- Unconjugated estriol (uE3) – a form of estrogen from the placenta and fetus
- Inhibin A – a hormone released by the placenta
The levels of these four markers give doctors insights into the likelihood of conditions such as Down syndrome, Trisomy 18, and neural tube defects.
Purpose of the Quadruple Marker Test
The primary purpose of the quad test for pregnancy is to evaluate the risk (not a diagnosis) of certain chromosomal/be, genetic, or metabolic disorders. It provides physicians with information about:
- Detecting Down syndrome (Trisomy 21) and Trisomy 18
- Identifying spina bifida or other neural tube defects
- Following fetal development
- Considering further testing when indicated
When is the Quadruple Marker Test Done?
Timing plays a crucial role. The quadruple marker test window is between 15 to 20 weeks of pregnancy, with the ideal time being around 16–18 weeks.
If the double marker test (usually done in the first trimester) was missed or inconclusive, the quadruple test serves as the next step to assess the baby’s health in the second trimester.
Quadruple Marker Screening in Pregnancy: Who Should Take It?
A doctor may recommend you take the quadruple marker screening test in pregnancy if you:
- Are 35 years of age or older (higher risk of chromosomal abnormalities)
- Have a family history of genetic conditions
- Had abnormal ultrasound findings
- Had a previous pregnancy with chromosomal abnormalities
- Did not get early screening during the first trimester
For low-risk pregnancies, many doctors will still suggest this screening, as part of a standard maternal screening test, to provide peace of mind.
Quadruple Marker Test Procedure
The quadruple blood test is simple and non-invasive.
Step-by-step procedure:
- A tiny blood sample is collected from your arm.
- The sample is sent to a lab for analysis.
- Results are usually available in 3 to 5 days.
There’s no risk to you or your baby, and you can continue your normal activities after the test. For accurate results, it’s best to get tested at a reliable diagnostic centre like the best laboratory in Coimbatore.
Quadruple Test Normal Values and Interpretation
Each of the four markers has a specific range that can vary by lab and pregnancy stage. Generally:
| Marker | Normal Range | Significance |
| AFP | 0.5 -2.0 MoM | High may indicate neural tube defects |
| hCG | 0.5 -2.0 MoM | High may suggest Down syndrome |
| Estriol (uE3) | 0.5 -2.0 MoM | Low may indicate chromosomal abnormalities |
| Inhibin A | 0.5 -2.0 MoM | High may indicate Down syndrome |
Doctors interpret results using MoM (Multiples of Median), which is a standardized way to compare your test result with the average for your gestational age.
If your results show higher or lower than normal values, your doctor may recommend an ultrasound, amniocentesis, or other confirmatory tests for accurate diagnosis.
Interpretation of a positive quadruple marker test
A positive quadruple marker test suggests that the test has detected an increased risk for some type of chromosomal or structural abnormality. It does not confirm that your baby has a diagnosis.
For example, a positive result could mean there is a risk for:
- Down syndrome (trisomy 21)
- Trisomy 18 (significant developmental delays)
- Spina bifida or other neural tube defect
Your doctor will most likely recommend follow-up testing, such as amniocentesis or a detailed ultrasound, to confirm the diagnosis
Difference Between Double Marker and Quadruple Test
The difference between the double marker and the quadruple test mainly lies in timing and the number of markers measured:
- Double marker test: Done in the first trimester (11–14 weeks); measures two markers, PAPP-A and hCG.
- Quadruple marker test: Done in the second trimester (15–20 weeks); measures four markers: AFP, hCG, estriol, and inhibin A.
Both aim to screen for genetic disorders, but the quad test gives a more detailed risk assessment.
Benefits and Limitations
Benefits:
- Non-invasive and safe
- Helps in early detection of chromosomal conditions
- Assists in better pregnancy management
- Provides reassurance for expecting parents
Limitations:
- It’s a screening test, not a diagnosis
- May show false positives or false negatives
- Follow-up tests may be needed for confirmation
Conclusion
The quadruple marker test is an important tool in modern prenatal care. It is designed to help confirm that your baby is developing normally and alert doctors early to potential risks.
Receiving the results can be a somewhat anxious experience, but remember that it is only a screening test and not a diagnosis. After an abnormal result, with the appropriate medical management and care, most pregnancies will progress normally.
For accurate Quadruple Marker testing and expert prenatal guidance, visit our scan centre or contact us today for an appointment.
FAQ
1. Which week is best for a quadruple marker test?
The best time for a quadruple marker test is between 15 to 20 weeks of pregnancy, ideally around 16–18 weeks.
2. Is a quadruple test done in an empty stomach?
No. You don’t need to fast before the quadruple test. It can be done after a normal meal.
3. Which is better, double marker or quadruple test?
Both are important. The double marker test is done in the first trimester, while the quadruple test in the second trimester gives a more detailed risk analysis if the earlier test was missed or unclear.
4. What is the cost of a quadruple marker test?
The quadruple marker test cost in India usually ranges from Rs 2,000 to Rs 4,500, depending on the lab and city.
5. What is the difference between NIPT and quad test?
The NIPT (Non-Invasive Prenatal Test) analyzes fetal DNA in the mother’s blood for very accurate results, while the quad test measures hormone levels to estimate risk. NIPT is more precise but also more expensive.
6. Is a quadruple marker test necessary after NIPT?
Usually, no. If you’ve already done NIPT and received clear results, the quadruple marker test may not be needed unless your doctor advises it for additional screening.
