Quadruple Marker with Graph - 2nd Trimester
Understanding Quadruple Marker with Graph - 2nd Trimester
What is Quadruple Marker with Graph - 2nd Trimester?
A Quadruple Marker with Graph - 2nd Trimester test is the most common blood screening test done between the 14th and 22nd weeks (ideal 15-20 weeks, i.e., second trimester) of pregnancy to determine whether the baby is at risk for certain birth defects. It offers valuable information to ensure the well-being of both the mother and the unborn child.
A Quadruple Marker with Graph - 2nd Trimester test is a prenatal screening test tailored to provide expectant parents with insights into the developing baby's health. It analyzes specific markers in the mother’s blood to assess the risk of chromosomal abnormalities, such as Down Syndrome (Trisomy 21) and Edwards Syndrome (Trisomy 18), wherein extra copies of chromosome 21 and 18 are present and affect the baby's physical and intellectual development. It also screens for neural tube defects like spina bifida (a spinal cord defect) and anencephaly (a brain defect). These birth defects can result in nerve damage, learning disabilities, paralysis, or stillbirth.
The Quad in Quadruple Marker with Graph - 2nd Trimester test refers to the four specific markers measured in the mother’s blood during the screening. These include Alpha-fetoprotein (AFP), Human Chorionic Gonadotropin (hCG), Unconjugated Estriol (uE3), and Inhibin A. When assessed collectively, the levels of these markers help estimate the likelihood of certain fetal abnormalities that can affect the baby’s growth and development. Timely detection of these abnormalities is vital for ensuring comprehensive prenatal care and effectively addressing potential health problems. In addition to the traditional Quad marker analysis, the inclusion of a graphical representation enhances the interpretability of results.
A Quadruple Marker with Graph - 2nd Trimester test is a screening test only; any abnormal result does not mean the unborn baby has a birth defect or genetic condition. It only tells whether the unborn baby is at risk of developing certain abnormalities, and further testing is required to confirm the diagnosis.
The recommendation of a Quadruple Marker with Graph - 2nd Trimester test is often based on maternal age, medical history, and individual risk factors for chromosomal abnormalities. Pregnant women should consult their doctor to determine the most appropriate screening or diagnostic test based on their specific circumstances.
No special preparation is required before undergoing a Quadruple Marker with Graph - 2nd Trimester test. However, a woman needs to be prepared to provide informed consent before undertaking this test. The laboratory personnel will explain the purpose, benefits, and limitations of this test.
Abnormal lab test results represent only the risk but not the diagnostic outcomes. Increased risk does not mean the baby is affected; further tests must be performed before a confirmed diagnosis can be made. Talk to your doctor about your specific test results.
What is Quadruple Marker with Graph - 2nd Trimester used for?
A Quadruple Marker with Graph - 2nd Trimester test is done:
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To assess the risk of certain chromosomal abnormalities in the developing baby.
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To assess the risk of Down Syndrome (Trisomy 21) in the developing baby.
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To assess the risk of Edwards Syndrome (Trisomy 18) in the developing baby.
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To assess the risk of neural tube defects like spina bifida in the developing baby.
What does Quadruple Marker with Graph - 2nd Trimester measure?
Contains 4 testsA Quadruple Marker with Graph - 2nd Trimester test measures the levels of four specific markers in a pregnant woman's blood. These markers are -Alpha-Fetoprotein (AFP), Human Chorionic Gonadotropin (hCG), Unconjugated Estriol, and Inhibin-A.
The analysis of these four markers and other factors like maternal age and gestational age helps assess the risk of certain conditions in the developing baby. The graph in a Quadruple Marker with Graph - 2nd Trimester provides a visual representation of the levels of these markers during pregnancy.
It is noteworthy that a Quadruple Marker with Graph - 2nd Trimester is a screening test, and any abnormal results may prompt further diagnostic testing for confirmation. Pregnant women should discuss their results and implications with their doctor.
Inhibin A
The Inhibin A test measures the level of inhibin A in the blood. It is a hormone primarily produced by the ovaries in women. It plays a key role in regulating menstrual cycle and ovarian function by inhibiting the production of follicle-stimulating hormone (FSH). During pregnancy, elevated levels of Inhibin A may point towards a risk of certain chromosomal abnormalities like Down’s syndrome etc., in the fetus.
The Inhibin A test is particularly useful in assessing ovarian function, fertility assessment, prenatal screening and diagnosing certain ovarian cancers.
Know more about Inhibin A
HCG Beta Total Quantitative, Maternal
An HCG Beta Total Quantitative, Maternal test measures the levels of human chorionic gonadotropin (hCG) hormone in the blood. hCG is released in the blood during pregnancy and can be detected as early as 10 days after conception. The levels of this hormone gradually rise every 2 to 3 days (or 48 to 72 hours) and peak around 8 to 11 weeks after conception. After reaching the peak, the hCG levels decrease and remain steady for the rest of the pregnancy.
Know more about HCG Beta Total Quantitative, Maternal
Unconjugated Estriol
The Unconjugated Estriol test is used to measure Unconjugated Estriol (uE3), a type of estrogen that is particularly significant during pregnancy. It is produced by both the fetus and the placenta. The levels of uE3 in the mother's blood can give insights into the baby's well-being and can be crucial for identifying certain risks and complications in pregnancy.
Know more about Unconjugated Estriol
Alpha Feto Protein, Maternal
An Alpha Feto Protein, Maternal test measures the amount of Alpha Fetoprotein in expectant mothers usually during the second trimester (14th and 22nd weeks). AFP is a protein produced by the fetus, primarily by the fetal liver and yolk sac, and it passes into the mother's blood. The test is typically performed to screen for certain fetal abnormalities, particularly neural tube defects (NTDs) such as spina bifida and anencephaly, as well as chromosomal abnormalities like Down syndrome (trisomy 21), Edwards syndrome (Trisomy 18), etc.
Detecting these abnormalities early in pregnancy allows for appropriate medical management and intervention.
Know more about Alpha Feto Protein, Maternal
Interpreting Quadruple Marker with Graph - 2nd Trimester results
Interpretations
Pregnancy Weeks |
AFP |
HCG |
Estriol |
Inhibin A |
14 |
27.20 ng/mL |
40370 mIU/mL |
0.37 ng/mL |
208.75 pg/mL |
15 |
32.01 ng/mL |
32200 mIU/mL |
0.55 ng/mL |
222.90 pg/mL |
16 |
37.67 ng/mL |
25690 mIU/mL |
0.76 ng/mL |
194.20 pg/mL |
17 |
44.33 ng/mL |
20490 mIU/mL |
1.00 ng/mL |
201.30 pg/mL |
18 |
52.16 ng/mL |
16340 mIU/mL |
1.25 ng/mL |
196.20 pg/mL |
19 |
61.38 ng/mL |
13040 mIU/mL |
1.50 ng/mL |
226.90 pg/mL |
20 |
72.33 ng/mL |
10400 mIU/mL |
1.76 ng/mL |
253.70 pg/mL |
21 |
85.08 ng/mL |
8295 mIU/mL |
1.99 ng/mL |
282.10 pg/mL |
22 |
100.02 ng/mL |
6620 mIU/mL |
2.30 ng/mL |
292.30 pg/mL |
Abnormality |
Cut off |
Detection rate |
False-positive rate |
Neural tube defects |
≥ 2.5 MoM (Multiples of median) |
70-75 % |
2-4 % |
Down Syndrome (Trisomy 21) |
1: 250 |
75 -80 % |
5 % |
Edwards Syndrome (Trisomy 18) |
1:100 |
60 % |
0.3 % |
Reference range may vary from lab to lab*
The base of screening tests is a statistical analysis of patient’s data which includes the demographic (statistical study of populations) and biochemical (laboratory) data.
Confirmation is mandatory by amniocentesis.
The results are illustrated in the form of a graph in the test report.
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Positive quadruple marker test usually indicates that the unborn child has a high risk of neural tube defects and chromosomal disorders like Down's syndrome, Patau syndrome, etc. More specific tests like amniocentesis are then advised to make a definitive diagnosis
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High levels of inhibin A usually indicate Down's syndrome whereas low levels might be associated with Edward's syndrome or trisomy 18. Sometimes, variable levels of inhibin A may also be present, and they are usually associated with trisomy 13 or Patau syndrome