All About Double Marker Test in Pregnancy
The stage of pregnancy is indeed thrilling, but it is also filled with so many questions and decisions. One of the important tests in early pregnancy is called the Double Marker Test. What is it? To explain in simple words, the Double Marker Test is a blood test done to screen if your baby is at risk for certain birth defects or genetic disorders, like Down syndrome.
But why is it essential? It assists the medical practitioners highlight the potential issues that may arise during the pregnancy allowing for better planning, further testing, and informed decision-making.
The Process of Double Marker Test: Steps Involved
Now, how is this test done? The procedure is quite simple. You will be required to give a blood sample, which is usually collected from the cubital fossa. The sample is analyzed to check the concentration of two specific biomarkers in your blood, namely hCG (Human Chorionic Gonadotropin) and PAPP-A (Pregnancy Associated Plasma Protein A).
These two markers indicate whether the baby is likely to have some chromosomal abnormalities. But there is no need to panic; it is a blood test with no special requirements needed beforehand.
When Is The Double Marker Test Conducted?
An expectant mother has to pay attention to the timing of the test, which has to fall between the first trimester of pregnancy, specifically from the 11th week to the 13+6 weeks. The Results are most reliable during this phase. If performed sooner or later, the accuracy of the results might be compromised.
How Effective Is The Double Marker Test?
As with any other medical examination, the Double Marker Test is not foolproof. It is highly sensitive, meaning it has a good ability to detect some conditions, but does not guarantee accuracy. The examination will suggest whether the baby is at increased or lesser chances of having chromosomal challenges. There is always the possibility of misleading results. For instance, the test may wrongly suggest higher chances of complications when the baby is in fact healthy. There are cases where some disorders go undetected also.
What Is Measured in Double Marker Test?
The test measures the quantity of hCG and PAPP-A found in the patient’s blood.
hCG: This is a hormone that is secreted by the placenta when a woman is pregnant. The presence of too much or too little of hCG may suggest certain abnormal genetic conditions.
PAPP-A: This protein is further produced by the placenta, and levels lower than normal increases the probability of certain genetic diseases such as Down syndrome.
When combined with the patient’s age, weight, medical history, and other factors, these markers aid in determining the probability of the patient’s baby suffering from certain disorders.
What Conditions Does the Double Marker Test Screen For?
The Double Marker Test is primarily designed to screen the patient for three major chromosomal disorders.
Down Syndrome (Trisomy 21) – a condition in which a baby is born with an additional copy of chromosome 21 causing various intellectual disabilities along with several other medical issues.
Edwards Syndrome (Trisomy 18) – Rare but devastating congenital condition that leads to grave physical and developmental complications usually ending in miscarriage or death at a very early stage.
Patau Syndrome (Trisomy 13)- Another severe genetic disorder which leads to serious difficulties in the child’s development and is likely to be born dead or die shortly after birth.
Benefits of the Double Marker Test
Potential problems can be detected early, and this is one of the biggest advantages of the Double marker test. If the test suggests that there could be a risk of a hereditary disorder, then further confirmatory tests like amniocentesis or CVS (Chorionic Villus Sampling) can be performed.
Another advantage is that it’s non-invasive, which means that there are no risks to the unborn child. It is as simple as giving a blood sample—there are no surgical procedures involved, nor does the patient require long hospital stays.
Risk and Limitations of the Double Marker Test
While the Double Marker Test is a valuable tool, there are some limitations. As mentioned before, the test does not have a guarantee of accuracy. It does not provide a diagnosis, but rather assesses the risk for certain conditions. If the screening yields a positive result, it does not mean a confirmatory diagnosis can be made, though the chances of having a disorder are higher which can lead to undue anxiety.
Moreover, the test only considers a limited number of disorders (for example, Down syndrome), hence it will not identify all possible congenital anomalies. Therefore, a normal result does not assure an uncomplicated pregnancy.
How to interpret double marker test results.
So, you had the exam done and now you are considering what results you could get from it. Your healthcare provider will interpret the results based on the ratio of the risk which takes into consideration several of your biomarkers and age. For instance:
Low-risk result means that there is low probability for your newborn to suffer from a genetic disorder.
High-risk result indicates that further tests such as amniocentesis may be required to ascertain the diagnosis.
Double Marker Test versus Triple Marker Test
You may be familiar with the term the ‘Triple Marker Test’. Now, let us find out how it is different from the Double Marker Test. The significance of difference is that the Triple Marker Test contains another marker, known as ‘estriol’. This aids in better screening of certain congenital birth defects, especially Down syndrome. The said test is usually done later in the pregnancy, roughly between 15 to 20 weeks.
How to prepare for the Double Marker Test
There aren’t many steps involved in preparing for the Double Marker Test. It only requires drawing out a blood sample and little else. Nevertheless, be sure to tell your physician about any current health issues, treatment plans, or even allergies. This is important as it can greatly change how they read the results.
Cost of the Double Marker Test
Like many other medical tests, the Double Marker Test has varying prices depending on the person’s region, healthcare provider, and insurance policy. In India, the prices typically range from ₹2,000 to ₹8,000. It’s better to ask your doctor or health insurance representative if the test is included in the benefits package provided.
Conclusion and Final Thoughts
To sum up, the Double Marker Test is one of the major aspects of prenatal care today. The test provides an early screening opportunity to assess the risks of certain genetic disorders during pregnancy. Even though the test does not have the ability to directly diagnose conditions, it is useful as a risk evaluation test. This helps parents gain vital information that assists them in making decisions about other tests and managing the pregnancy.
