Double Marker Test
The double marker test is a prenatal screening test that is done to assess the risk of certain chromosomal abnormalities, particularly Down syndrome, and to detect any potential hormonal imbalances during pregnancy. It is typically performed between the 10th and 14th week of pregnancy.
The test measures two components in the mother's blood: human chorionic gonadotropin (hCG) and pregnancy-associated plasma protein-A (PAPP-A). Abnormal levels of these substances may indicate an increased risk of chromosomal abnormalities or fetal developmental problems.
If the results of the double marker test are abnormal, further testing such as an ultrasound or amniocentesis, may be recommended to confirm the diagnosis. It is important to note that the double marker test is a screening test, not a diagnostic test, and that a positive result does not necessarily mean that the baby has a chromosomal abnormality or other problem.
It is very important to discuss the risks and benefits of the double marker test with your doctor before deciding whether or not to have the test. The test is optional and not all women choose to have it.
Why is a double marker test performed?
The first-trimester screening (dual marker test and NT scan) is optional. But, if you're over the age of 35 or have a family history of specific illnesses, the screening (and others like the cell-free DNA test) is suggested.
Understanding that the result merely tells you if you have a higher chance of trisomies is essential. It does not determine whether or whether your baby has any abnormalities.
When deciding whether or not to have a double marker test, consider what the findings might imply to you in the long term.
- Does learning about probable anomalies make you feel better or worse?
- Would you want to undergo more intrusive testing if the results indicated a higher risk?
- Would the findings affect how you manage your pregnancy?
It all depends on personal choice and individual medical history.
How is this test done?
The double marker test is done as a basic blood test. Because this test does not require fasting, you can eat or drink normally before your visit unless otherwise indicated.
Results will show a low-, moderate-, or high-risk.
Low-risk (negative) is considered a "normal" result and indicates that your baby is unlikely to have chromosomal abnormalities.
If your result is within the normal range, you will only be advised for additional testing if there is another sign (such as family history, age, etc.) or if you want to learn more for another reason.
But, a low-risk test does not automatically imply that your kid will be well. It's also worth noting that the first-trimester screening only checks for Down syndrome, trisomy 13, and trisomy 18 markers, not other diseases.
If your screening results show that you are at moderate- or high-risk for abnormalities ("screen-positive"), you have to consult a genetic counselor to learn more.
More conclusive and often invasive procedures, such as noninvasive prenatal testing (NIPT), amniocentesis, or chorionic villous sample, can be used to confirm your results. While some of these tests may endanger your pregnancy, they deliver a conclusive result.
When the double marker test is performed early in your pregnancy, the results give you enough time to make key decisions regarding additional testing, medical treatments, and the overall management of your pregnancy and birth.
Is there any risk in using the double marker test?
The double marker test is completely risk-free. It is a simple, noninvasive blood test. Follow your doctor's recommendations and contact your physician if you have any concerns.