What Is the Quadruple Marker Test?
The Quadruple Marker Test is a second-trimester maternal blood screening test used to estimate the likelihood of certain chromosomal conditions and neural tube defects during pregnancy.
It is called a "quadruple" marker test because it measures four substances associated with pregnancy in the mother's blood. The results are combined with relevant pregnancy information to calculate an individualized screening risk.
What Does the Quadruple Marker Test Measure?
The Quadruple Marker Test evaluates four biochemical markers:
• Alpha-fetoprotein (AFP)
• Human chorionic gonadotropin (hCG)
• Unconjugated estriol (uE3)
• Inhibin A
The levels of these markers vary during pregnancy. The laboratory uses the measured values together with gestational age and other relevant maternal and pregnancy information to calculate the screening result.
Why Is the Quadruple Marker Test Done?
The Quadruple Marker Test can provide additional information about the likelihood of selected chromosomal conditions during the second trimester. It may also help assess the likelihood of certain neural tube defects through the AFP measurement.
It is a screening test and is not intended to provide a definitive diagnosis. The result should be interpreted together with ultrasound findings and other pregnancy information.
Which Conditions Can the Quad Test Screen For?
The Quadruple Marker Test is primarily used to estimate the likelihood of certain chromosomal conditions, including:
• Trisomy 21 (Down syndrome)
• Trisomy 18 (Edwards syndrome)
The AFP component can also contribute to screening for an increased likelihood of certain open neural tube defects. The exact interpretation depends on gestational age, laboratory methodology and the clinical situation.
When Is the Quadruple Marker Test Done?
The Quadruple Marker Test is generally performed during the second trimester of pregnancy, within the gestational age range recommended for the screening protocol.
Accurate dating of the pregnancy is important because the levels of the four biochemical markers change as pregnancy progresses. Your doctor or fetal medicine specialist can advise you about the appropriate timing based on your pregnancy dates and ultrasound assessment.
How Is the Quadruple Marker Test Performed?
The Quadruple Marker Test is performed using a blood sample collected from the mother. The sample is analyzed by a specialized laboratory to measure the four biochemical markers.
The laboratory combines the marker values with relevant pregnancy information to calculate the estimated screening risk for the conditions included in the test.
Understanding the Quadruple Marker Test Result
The Quadruple Marker Test provides a calculated screening risk rather than a confirmed diagnosis. The result may indicate a lower or higher likelihood of the conditions being screened for.
A screening result should always be interpreted in the context of the pregnancy, including gestational age, ultrasound findings, maternal factors and other available screening information.
What Does a High-Risk Result Mean?
A high-risk or increased-risk Quadruple Marker Test result means that the calculated likelihood of a particular condition is higher than the screening threshold used by the laboratory.
A high-risk screening result does not confirm that the baby has a chromosomal condition or neural tube defect. Further evaluation may be recommended depending on the result and the overall clinical assessment.
What Does a Low-Risk Result Mean?
A low-risk result indicates a lower calculated likelihood of the screened conditions. However, it does not completely rule out chromosomal abnormalities, genetic conditions or structural abnormalities.
Routine antenatal care and recommended ultrasound examinations should continue even when the Quadruple Marker Test indicates a low-risk result.
Importance of Accurate Pregnancy Dating
Accurate gestational age is particularly important when interpreting maternal serum screening tests. The concentrations of AFP, hCG, uE3 and inhibin A naturally change throughout pregnancy.
An incorrect estimation of gestational age can affect the calculated screening risk. Ultrasound assessment can help establish or confirm pregnancy dating when required.
Quadruple Marker Test and Ultrasound
The Quadruple Marker Test and fetal ultrasound provide different types of information. The blood test evaluates biochemical markers, while ultrasound examines fetal development, anatomy, growth and other structural features.
A detailed second-trimester ultrasound, including appropriate fetal anatomical assessment, remains an important part of prenatal care regardless of the screening result.
Quadruple Marker Test and NIPT
The Quadruple Marker Test and NIPT are different prenatal screening approaches. The Quad Test measures four biochemical markers in maternal blood, while NIPT analyzes cell-free DNA associated with the pregnancy.
The appropriate screening option depends on factors such as gestational age, previous screening, ultrasound findings, pregnancy history, available testing and individual preferences. A fetal medicine specialist can explain the differences between available screening options.
What Happens After a High-Risk Quad Test?
If the Quadruple Marker Test indicates an increased screening risk, the result should be reviewed carefully rather than interpreted as a diagnosis.
Depending on the individual pregnancy, further assessment may include detailed ultrasound, additional screening such as NIPT, genetic counselling or diagnostic testing when clinically appropriate.
Quadruple Marker Test Counselling
Prenatal screening results can sometimes be difficult to understand. Specialist counselling can help explain the calculated risk, the limitations of the screening test and the possible options for further assessment.
At Promise Fetal Medicine & Pregnancy Scan Centre, screening results can be considered alongside ultrasound findings and other relevant pregnancy information to support individualized prenatal care.
Quadruple Marker Test in Jalandhar
Promise Fetal Medicine & Pregnancy Scan Centre in Jalandhar provides specialist fetal medicine, pregnancy scan and prenatal screening services, including counselling related to second-trimester maternal serum screening.
Our approach focuses on individualized assessment and helping expectant parents understand screening results in the context of ultrasound findings, pregnancy history and other relevant clinical information.
Book a Quadruple Marker Test Consultation
If you are in the second trimester and have been advised to undergo a Quadruple Marker Test, or if you need help understanding a maternal serum screening result, consult a fetal medicine specialist for appropriate guidance.
Contact Promise Fetal Medicine & Pregnancy Scan Centre in Jalandhar for Quadruple Marker Test counselling, prenatal screening and specialist fetal medicine consultation.
