Double Marker vs Triple Marker Test: Key Differences Every Parent Should Know
Time to read 6 min
Time to read 6 min
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Pregnancy is the most beautiful and important phase of a woman’s life. During this phase, expectant parents need to monitor the health and well-being of both the mother and the baby. Prenatal screening is a crucial procedure that helps track the health of the mother and baby during pregnancy.
Prenatal screening can help diagnose potential chromosomal disorders and certain genetic disorders such as Down syndrome. It can help recognize the potential health risks for the mother, including anemia and gestational diabetes. These screening procedures allow early medical interventions and lifestyle modifications for better outcomes and offer proper guidance and reassurance for a healthy pregnancy.
When it comes to prenatal screening, marker tests are the most common diagnostic tests to recognize the risk of chromosomal abnormalities in the baby. These tests assess certain substances in the amniotic fluid or the mother’s blood. Marker tests look for proteins, hormones, and other chemicals associated with the developing fetus and fetal development.
Abnormal marker levels may indicate an increased risk of conditions such as neural tube defects, Edward syndrome (Trisomy 18), or Down syndrome (Trisomy 21). Marker tests involve the two markers of the double marker test and the triple marker test. The double marker test is used for early screening during the first trimester, while the triple marker test is performed in the second trimester for better risk assessment.
This article is all about the comprehensive understanding of the difference between the double marker and triple marker test, so keep reading.
The double marker test is performed during the first trimester of pregnancy between 11 and 14 weeks. It assesses the possibility of chromosomal abnormalities in the developing baby, such as Trisomy 18 and Trisomy 21.
The double marker test analyzes certain substances in the blood sample of the mother, including PAPP-A (pregnancy-associated plasma protein A) and Free beta-hCG (human chorionic gonadotropin).
Usually, the dual marker test is performed in combination with an ultrasound in order to reconfirm the accuracy. This test is considered safe and efficiently detects the possibility of developing certain chromosomal concerns in the baby, allowing the healthcare providers to understand if further diagnostic tests are required.
The triple marker test is performed during the second trimester of pregnancy between 15 and 20 weeks. This test detects the risk of chromosomal abnormalities, including neural tube defects, trisomy 18, and Down syndrome in the developing baby, potentially leading to additional diagnostic tests.
The triple marker test measures certain substances in the blood of the mother, including AFP (alpha-fetoprotein), hCG (human chorionic gonadotropin), and Estriol (unconjugated estriol). It is a non-invasive method to look for potential birth defects and check if the values are within the normal range for chromosomal concerns.
Both double and triple marker tests are similar kinds of prenatal screening tests and other prenatal tests performed for early detection to diagnose potential chromosomal abnormalities; however, they differ in terms of timing and other aspects.
Here are the key differences between the double marker vs triple marker tests to help make informed decisions :
Double Marker Test: Performed during 11th to 14th weeks of pregnancy (first trimester). This is an early screening test that allows timely detection, and further testing is necessary.
Triple Marker Test: Performed during the 15th to 10th weeks of pregnancy (second trimester). It helps detect chromosomal abnormalities and neural tube defects.
Double Marker Test: Pregnancy Associated Plasma Protein-A (PAPP-A) and low levels of this protein show a greater risk of chromosomal conditions. Free beta-HCG and its abnormal levels show the possibility of a chromosomal condition. Usually combined with a nuchal translucency ultrasound procedure to enhance accuracy.
Triple Marker Test: Alpha-fetoprotein (AFP), abnormal levels suggest chromosomal problems or neural tube defects in the baby. Human Chorionic Gonadotropin (hCG), abnormal levels show chromosomal issues. Unconjugated Estriol and its low levels show chromosomal conditions.
Double Marker Test: Mainly looks for Trisomy 18 and Trisomy 21 (Down syndrome), allowing timely risk assessment to manage chromosomal conditions.
Triple Marker Test: Looks for Trisomy 18, Trisomy 21 (Down syndrome), and neural tube defects, allowing better risk evaluation during the second trimester.
Double Marker Test: Higher accuracy for trisomy 18 and Down syndrome due to early screening.
Triple Marker Test: Offers a wider assessment for neural tube defects and chromosomal abnormalities.
Double Marker Test: In case of high risk, healthcare professionals recommend non-invasive prenatal testing for accurate diagnosis.
Triple Marker Test: Abnormal test results may need NIPT, amniocentesis, or a comprehensive ultrasound based on the detected risk.
Refer to the table to get a clearer picture of the double marker vs triple marker differences:
Aspect |
Double Marker Test |
Triple Marker Test |
Timing of the test |
First trimester (11-14 weeks) |
Second trimester (15-20 weeks) |
Purpose of the test |
Detect trisomy 18 and Down syndrome |
Detects trisomy 18, Down syndrome, and neural tube defects |
Markers involved |
PAPP-A and free beta-hCG |
AFP, Estriol, and hCG |
Accuracy |
Higher for early chromosomal abnormalities detection |
Broader screening range, including neural tube defects and chromosomal abnormalities |
Prenatal screening offers crucial insights into the health and well-being of the mother and the baby. Double marker vs triple marker tests are vital tools for early detection and broader screening during various stages of pregnancy.
The double marker test is performed during the early pregnancy in the first trimester to look for chromosomal conditions (trisomy 18 and Down syndrome), while considering the medical history, the triple marker test is performed during the later phase, the second trimester of the pregnancy, to check for chromosomal and neural tube defects.
Early screening helps make crucial decisions and detect if further tests are required, and the triple marker offers additional information for a complete risk assessment. Parents should seek professional medical advice and be aware of these tests to ensure their baby’s proper growth and well-being.
Book your Double or Triple Marker Test with MyDiganostics at an affordable cost and get the comprehensive insights into the mother's and the baby’s health and well-being.
Both of these prenatal screening tests can be performed during the same pregnancy at different timings. Generally, healthcare professionals recommend the most suitable test to avoid unnecessary repetition and achieve accurate outcomes. Both can offer a wider picture; however, doctors usually choose depending on the risk factors.
Maybe and may not be because it completely depends on the double marker test results and how healthcare provider’s recommendations. It's not mandatory to do a triple marker after normal double marker test results.
Generally, the double marker test is considered more accurate for the definitive diagnosis and timely diagnosis of chromosomal abnormalities, and the triple marker test offers a wider screening in later stages of pregnancy.
None of the double marker and triple marker tests can completely replace each other, as both of these tests are performed at different trimesters of pregnancy for different purposes. Each of these tests has its own purpose and timing, considering family history, and they are complementary tools to assess the prenatal risk.
***Medical Disclaimer - The following information is for educational purposes only. No information provided on this website, including text, graphics, and images, is intended as a substitute for professional medical advice. Please consult with your doctor about specific medical advice about your condition(s).
