What to Expect During a Double Marker Screening

Pregnancy is a time of joy, anticipation, and often, questions. As part of early prenatal care, several screening tests are recommended to help parents and doctors monitor the baby’s development. One such test is the double marker screening test. Though it sounds clinical, it’s a routine part of many pregnancies and can provide valuable information about chromosomal conditions.

This blog will walk you through what the double marker test is, how it’s conducted, why it's typically recommended, and what you can expect during the process. Whether you're a first-time parent or simply seeking more information, this guide will give you a clear picture, without overwhelming you.

What is a Double Marker Test?

The double marker test, also known as prenatal double marker screening, is a non-invasive blood test done during the first trimester of pregnancy. It is usually performed between the 11th and 14th week of gestation.

This test primarily measures the levels of two specific markers in the mother's blood:

• Free Beta-human Chorionic Gonadotropin (?-hCG)
• Pregnancy-Associated Plasma Protein-A (PAPP-A)

The levels of these markers, when assessed along with an ultrasound finding called nuchal translucency (NT), can help estimate the chances of certain chromosomal abnormalities, such as Trisomy 21 (Down syndrome), Trisomy 18 (Edwards syndrome), and Trisomy 13 (Patau syndrome).

It is important to note that this is a screening test, not a diagnostic one. It does not confirm any condition but simply indicates the probability of one.

Why is Prenatal Double Marker Screening Done?

While pregnancy is typically monitored with routine ultrasounds and checkups, double marker screening helps assess the risk of certain genetic abnormalities early on. If results show a higher probability, doctors may recommend further diagnostic tests like non-invasive prenatal testing (NIPT), amniocentesis, or chorionic villus sampling (CVS) for confirmation.

The goal is early identification, so parents and healthcare providers can plan, support, and make informed decisions moving forward.

What to Expect During Double Marker Screening

Here’s a quick breakdown of what typically happens during the test:

• Timing: Conducted between 11 to 14 weeks of pregnancy
• Setting: Usually done at a diagnostic center or hospital
• Duration: Around 15–20 minutes for the sample collection
• Discomfort: Minimal, as it only involves a blood draw

You may be asked to come on an empty stomach or at a specific time of day, depending on your healthcare provider's instructions.

Once your blood is drawn, it’s sent to the lab for analysis. Your NT scan results (ultrasound) may also be considered during risk calculation. The combined data is used to estimate the probability of chromosomal anomalies.

Double Marker Screening Procedure Explained

Let’s take a closer look at how the procedure unfolds:

This report is typically discussed with your OB-GYN or a genetic counselor. Remember, a high-risk result doesn’t mean your baby has a condition—it just suggests that further testing may be beneficial.

Is Double Marker Screening Safe and What Does It Detect?

Yes, double marker screening is safe. It involves no risk to the baby and poses only minimal discomfort to the mother due to the blood draw. There’s no radiation, no anesthesia, and no invasive equipment involved.

What does it detect? While it doesn’t diagnose anything, it helps screen for the likelihood of the following conditions:

• Trisomy 21 (Down syndrome)
• Trisomy 18 (Edwards syndrome)
• Trisomy 13 (Patau syndrome)

These are among the more common chromosomal conditions that can affect development.

However, the accuracy of the double marker test is not absolute. Studies suggest a detection rate of around 85% for Down syndrome test when combined with NT scan results, but it may also return false positives or false negatives. That’s why confirmatory diagnostic tests may be advised in high-risk cases.

Conclusion

The double marker screening test is a widely used, low-risk method to assess potential chromosomal abnormalities during the early weeks of pregnancy. It forms part of a broader approach to prenatal care, providing expectant parents with helpful information to make informed decisions with their healthcare providers.

While receiving a "high-risk" result can be concerning, it’s important to remember that this is not a diagnosis, only a probability. Next steps, if needed, will be guided by your doctor and may include more detailed screening or diagnostic options.

At Apollo Diagnostics, you can access high-quality, accurate prenatal tests, including the double marker screening, conducted in a reliable and professional setting. Speak to your healthcare provider or visit your nearest Apollo Diagnostics center to learn more.