Triple Marker Test: Importance, Procedure, and Results
The test is especially recommended for pregnant women over the age of 35 or those with a family history of genetic disorders.
The Triple Marker Test is a prenatal screening test conducted during the second trimester of pregnancy. It helps in assessing the risk of chromosomal abnormalities and neural tube defects in the developing fetus. The test is especially recommended for pregnant women over the age of 35 or those with a family history of genetic disorders.
What is a Triple Marker Test?
The Triple Marker Test is a blood test that measures the levels of three key substances:
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Alpha-Fetoprotein (AFP): A protein produced by the fetal liver, high or low levels may indicate birth defects.
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Human Chorionic Gonadotropin (hCG): A hormone produced by the placenta; abnormal levels may suggest chromosomal disorders.
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Unconjugated Estriol (uE3): A form of estrogen produced by the fetus and placenta; low levels may indicate fetal abnormalities.
Why is the Triple Marker Test Important?
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Detects Chromosomal Abnormalities: Assesses the risk of Down syndrome (Trisomy 21) and Edwards syndrome (Trisomy 18).
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Identifies Neural Tube Defects: Helps detect conditions like spina bifida and anencephaly.
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Provides Risk Assessment: Aids in deciding whether further diagnostic tests are needed.
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Helps in Pregnancy Management: Guides doctors and parents in making informed decisions about pregnancy care.
Who Should Get a Triple Marker Test?
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Pregnant women above 35 years of age.
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Women with a family history of genetic disorders.
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Those with abnormal ultrasound findings.
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Women who had viral infections or harmful drug exposure during pregnancy.
When is the Triple Marker Test Done?
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The test is performed between 15 to 20 weeks of pregnancy, with the optimal period being 16-18 weeks.
Triple Marker Test Procedure
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A blood sample is taken from the pregnant woman’s arm.
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The sample is analyzed to measure AFP, hCG, and estriol levels.
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The results are evaluated along with maternal factors like age, weight, and medical history.
Interpreting Triple Marker Test Results
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Normal Risk: Indicates a low probability of chromosomal abnormalities or neural tube defects.
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High Risk: Suggests an increased likelihood of conditions like Down syndrome, requiring further diagnostic tests such as Amniocentesis or Chorionic Villus Sampling (CVS).
Triple Marker Test Normal Range
| Marker | Normal Range |
|---|---|
| AFP | 10-150 ng/mL |
| hCG | 10,000-100,000 mIU/mL |
| Estriol (uE3) | 0.5-3.5 ng/mL |
Difference Between Double Marker and Triple Marker Test
| Feature | Double Marker Test | Triple Marker Test |
| Markers Measured | Beta-hCG, PAPP-A | AFP, hCG, Estriol |
| Performed In | First trimester (9-13 weeks) | Second trimester (15-20 weeks) |
| Purpose | Detects early chromosomal abnormalities | Assesses risk of neural tube defects and chromosomal disorders |
Triple Marker Test Cost in India
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The cost of the Triple Marker Test varies based on location and healthcare provider, typically ranging between INR 2500 – INR 5000.
What if My Triple Marker Test is Positive?
A positive or high-risk result does not confirm a genetic disorder but suggests the need for further testing. Your doctor may recommend:
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Detailed Ultrasound Examination to check for fetal abnormalities.
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Non-Invasive Prenatal Testing (NIPT) for better risk assessment.
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Amniocentesis or CVS for a definitive genetic diagnosis.
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Regular monitoring and consultations for better pregnancy management.
Conclusion
The Triple Marker Test is a crucial prenatal screening tool that helps detect the risk of chromosomal and neural tube defects. Although it does not provide a definite diagnosis, it assists in determining the need for further tests and guiding pregnancy care. Expecting parents should discuss the results with their doctor for appropriate next steps.
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