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Double Marker Test- First Trimester

Also known as Dual Marker Test, Maternal Serum Screening (MSS) - First Trimester

₹1929~~₹2400~~ 19% Off

You need to provide

Blood

This test is for

Female

Test Preparation

A duly filled Maternal Serum Screen requisition form is mandatory.
Provide information like maternal date of birth (dd/mm/yy), last date of the menstrual cycle (LMP), number of fetuses (single/twins), diabetic status, body weight in kg, and history of IVF, smoking, and Trisomy 21 pregnancy.
Keep a hard copy of the latest pregnancy ultrasound report (Date of scan, CRL, NT in mm/NB, Level 1) - this is mandatory for combined risk assessment.
The test is valid between 9 to 13 weeks of gestation (the ideal time for combined risk assessment is between 11 to 13 weeks).

Understanding Double Marker Test- First Trimester

What is Double Marker Test- First Trimester?

A Double Marker Test- First Trimester, also known as a dual marker test, assesses specific biomarkers in a pregnant woman’s blood during the first trimester of pregnancy, usually between 11-13 weeks. It provides information about the risk of certain birth defects such as Down syndrome (Trisomy 21), Edward syndrome (Trisomy 18), and Patau syndrome (Trisomy 13) in the developing fetus.

Prenatal care is necessary to ensure a healthy pregnancy and successful childbirth. Early prenatal screenings identify potential health concerns and guide medical interventions when necessary. A Double Marker Test- First Trimester is an essential component of early prenatal assessment that offers invaluable insights into the developing fetus's chromosomal health. This test primarily focuses on two biomarkers in the maternal blood that the fetus and the placenta produce: human chorionic gonadotropin (hCG) and pregnancy-associated plasma protein A (PAPP-A).

The dual marker test screens the fetus for certain chromosomal abnormalities, particularly Down syndrome and Edwards' syndrome. These conditions result from the presence of extra copies of chromosomes 21 and 18, respectively, and affect the baby's physical and intellectual development. However, a Double Marker Test- First Trimester is just a screening test, not a diagnostic one. It does not determine whether your baby has abnormalities; instead, it tells whether the unborn baby is at risk of developing certain abnormalities.

The test results are reported as a risk score or probability of the fetus having a chromosomal abnormality. Test results within the expected range suggest a lower risk of chromosomal abnormalities, whereas high biomarker levels may indicate a higher risk of chromosomal abnormalities and prompt further testing. Furthermore, a screen-positive result (high risk) does not provide a diagnosis but suggests that additional diagnostic testing should be considered. Also, a screen-negative result (low risk) does not guarantee the absence of fetal defects.

For combined risk assessment, the nuchal translucency (NT) measurement, a USG marker shown to be effective in screening fetuses for Down syndrome and Patau syndrome, is also included in the risk calculation along with maternal demographic information like age, weight, smoking, diabetic status, IVF pregnancy, etc. However, it is to be noted that this test does not screen for neural tube defects.

No fasting is required for a Double Marker Test- First Trimester. However, inform your doctor about all your medical conditions or allergies before taking the test. Also, tell your doctor about the medications you are taking, as certain medications can affect the results of this test and might need to be discontinued.

Talk to your doctor about your specific test results. The accuracy of the results is subjective to the information provided in the screening form, and this information is mandatory for combined risk assessment.

What is Double Marker Test- First Trimester used for?

A Double Marker Test- First Trimester is done:

For the early risk assessment of chromosomal abnormalities, such as Down syndrome, Patau syndrome, and Edward syndrome in developing fetuses.
Especially in pregnant women above 35 years of age and those with a family history of birth defects and a history of insulin-dependent type 1 diabetes.

What does Double Marker Test- First Trimester measure?

The test is named “Double Marker” or “Dual Marker” as it primarily focuses on two biomarkers associated with chromosomal abnormalities: free beta-hCG (human chorionic gonadotropin) and PAPP-A (pregnancy-associated plasma protein-A). These, along with the USG marker and nuchal translucency (NT) measurement, are effective in Combined screening for Down syndrome and trisomy 13/18 in the fetus. This test only gives the risk for the presence of these chromosomal abnormalities in the developing fetus. A positive screen is not diagnostic but indicates that further evaluation should be considered.

hCG is synthesized by the placenta very early in pregnancy and can be detected in the blood 8-11 days after conception. Higher than normal levels of this hormone after 11 weeks of gestation indicate an increased risk for Down syndrome, while low levels indicate an increased risk for trisomy 18.

PAPP-A is a protein produced by the placenta that is needed for the implantation and maintenance of a healthy placenta (afterbirth). Low levels of PAPP-A before the 14th week of pregnancy suggest an increased risk of fetal chromosomal abnormalities.

Interpreting Double Marker Test- First Trimester results

Interpretations

All women should be screened with a dual marker test during pregnancy for any pre-birth abnormalities, irrespective of age. The ideal duration of this test is between the 10th and 13th weeks of pregnancy. But it can be done between the 9th and 13th weeks of pregnancy.

Answers to Patient Concerns & Frequently Asked Questions (FAQs) about Double Marker Test- First Trimester

Frequently Asked Questions about Double Marker Test- First Trimester

Q. What is a Double Marker Test- First Trimester, and why is it performed?

A Double Marker Test- First Trimester is a prenatal screening test that assesses the risk of chromosomal abnormalities in the developing fetus. It is performed to assess the risk of potential genetic conditions such as Down syndrome and Edwards’ syndrome.

Q. What is the difference between a Double Marker Test- First Trimester and an NT scan?

An NT scan is an ultrasound, and a Double Marker Test- First Trimester is a blood test. The doctor recommends both these tests during the first trimester to screen for the possible risk of chromosomal abnormalities in the unborn child.

Q. How early can a dual marker test be conducted during pregnancy?

A dual marker test is typically conducted during the first trimester of pregnancy, i.e., between weeks 9 and 13. But it is advised to get tested between 11 - 13 weeks along with NT values from the USG report as it gives Combined risk which is better.

Q. What is a Combined Risk Assessment?

The first-trimester screening combines two blood tests and a special ultrasound (with NT measurement in mm, CRL value, and nasal bone (NB)). In combined risk assessment, the risk score from blood tests is interpreted in conjunction with the nuchal translucency (NT) measurement and maternal demographic information like age, weight, smoking, diabetic status, IVF pregnancy, etc., to assess the overall risk profile. This increases both the sensitivity and specificity of the screening results.

Q. What does a negative screen mean?

A negative screen means it is unlikely the fetus has Down syndrome, trisomy 18. However, a negative screen does not guarantee the birth of a healthy baby. The screening test only screens for Down syndrome and trisomy 18; it is not a diagnostic test. The maternal demographic information provided at the time of testing is used in calculating the patient’s risk of having a fetus with Down syndrome or trisomy 18. Please check the demographic information to ensure the accuracy of the calculated results.

Q. What chromosomal abnormalities are screened by a Double Marker Test- First Trimester?

A Double Marker Test- First Trimester primarily screens for Down syndrome (Trisomy 21), Patau syndrome (Trisomy 13), and Edwards’ syndrome (Trisomy 18).

Q. How is a Double Marker Test- First Trimester performed, and is it safe for the baby?

The test involves a simple blood draw from the pregnant woman and poses no risk to the developing fetus. Furthermore, the test is non-invasive and carries no risks to the pregnancy. It is considered a safe screening test.

Q. Can a Double Marker Test- First Trimester identify the specific chromosomal abnormalities in the fetus?

A Double Marker Test- First Trimester is a screening test and not a diagnostic test, meaning it screens for the risk of chromosomal abnormalities and doesn’t identify the specific abnormality. Confirmatory tests are required for a definitive diagnosis.

Q. What is Down syndrome?

Down syndrome, also known as Trisomy 21, is a genetic disorder caused by the presence of an extra copy of chromosome 21 in a person's DNA (genetic material). It can cause various physical and intellectual challenges, such as almond-shaped eyes, a flat facial profile, a small nose, a protruding tongue, and low muscle tone. The affected individuals may take longer to achieve developmental milestones, such as walking and talking. They may also be at a higher risk for certain medical conditions, including congenital heart defects, gastrointestinal issues, hearing problems, vision issues, and respiratory infections.

Q. What is Edwards’ syndrome?

Edwards’ syndrome, also known as Trisomy 18, is a rare genetic disorder caused by the presence of an extra copy of chromosome 18 in a person's DNA (genetic material). It typically results in severe intellectual and developmental disabilities. It is characterized by a range of physical abnormalities, including a small head, low-set ears, a small jaw, clenched fists with overlapping fingers, and rocker bottom feet (a rounded sole on the bottom of the feet). Most babies born with Edwards’ syndrome have congenital heart defects, often requiring surgical intervention.

Q. What if a dual marker test is missed?

Suppose you miss the recommended dual marker test time frame; in that case, your doctor may recommend alternative tests, such as a quad marker screening test (typically performed between the 15th and 21st week of pregnancy), depending on the stage of pregnancy.