A million doubts regarding the foetus arise while you're in your third trimester of pregnancy. To identify any complications in your pregnancy, your gynaecologist might advise double marker reflex to NIPS Test to help you with smooth delivery. The double marker test, also known as maternal serum screening, is a part of the first-trimester screening. Even though it is not a conclusive scientific analysis, it can indicate whether chromosomal abnormalities are likely to exist. Instead of being diagnostic, this test is predictive. During the double marker reflex to NIPS test, a sample of your blood is drawn for additional examination to look for foetal abnormalities.

The chance of the foetus being born with chromosomal abnormalities like trisomy 21, trisomy 18, and trisomy 13 is assessed through non-invasive prenatal screening (NIPS). Little DNA wastes (fragments/ pieces of DNA) that are present in a pregnant woman's blood are analysed by this test.

What is the Double Marker Reflex to NIPS Test?

A million doubts regarding the foetus arise while you're in your third trimester of pregnancy. To identify any complications in your pregnancy, your gynaecologist might advise double marker reflex to NIPS Test to help you with smooth delivery. The double marker test, also known as maternal serum screening, is a part of the first-trimester screening. Even though it is not a conclusive scientific analysis, it can indicate whether chromosomal abnormalities are likely to exist. Instead of being diagnostic, this test is predictive. During the double marker reflex to NIPS test, a sample of your blood is drawn for additional examination to look for foetal abnormalities.

The chance of the foetus being born with chromosomal abnormalities like trisomy 21, trisomy 18, and trisomy 13 is assessed through non-invasive prenatal screening (NIPS). Little DNA wastes (fragments/ pieces of DNA) that are present in a pregnant woman's blood are analysed by this test.

What Is the Purpose of The Double Marker Reflex to NIPS Test?

To avoid problems before or after delivery, this test is frequently advised during the first trimester. Typically, the procedure is carried out between the 11th and 14th week of pregnancy. Pregnant women were enrolled in this observational test to examine combinations of traditional screening and non-invasive prenatal screening (NIPS). The purpose of the test is to evaluate which traditional screening is the best first-line screening strategy for NIPS.  It helps to diagnose diseases involving the sex chromosomes (X and Y).

What Does the Double Marker Reflex to NIPS Test Diagnose?

Blood samples are tested for beta-human chorionic gonadotropin (beta-hCG) and pregnancy-associated plasma protein A (PAPP-A) levels (PAPP-A). On average, female embryos have 22 pairs of XX chromosomes, while male embryos have 22 pairs of XY chromosomes. Trisomy is a chromosomal disorder caused by the presence of extra chromosomes. Trisomy 21, often known as Down syndrome, is a condition brought on by an extra copy of chromosome 21. Another typical chromosomal issue is having an extra copy of either chromosome 18 causing Edward's syndrome or chromosome 13 which causes Patau's syndrome.

NIPS measures Cell-free DNA (cfDNA), a form of genetic material that is secreted by placental cells circulating in the mother's blood during pregnancy. In general, the cfDNA from the placenta represents the genetic factor of developing the foetus. NIPS can be used to identify chromosomal abnormalities in placental cfDNA as early as the tenth week of pregnancy. Non-invasive prenatal screening (NIPS) can assist assess the possibility that a pregnant woman's growing foetus has a chromosomal problem. It is not a diagnostic test, thus it cannot confirm whether the foetus is impacted or not. If NIPS indicates an elevated risk for a specific chromosome issue, than diagnostic testing via chorionic villus sampling (CVS) or amniocentesis is recommended to determine the actual diagnosis.

Who Needs the Double Marker Reflex to NIPS Test?

During or following the tenth week of pregnancy, non-invasive prenatal screening (NIPS) is available. The pregnancy must be at least 10 weeks pregnant for samples to be accepted because any taken before this point are automatically rejected. For example, if you have a family history of a particular condition or you are above 35 years of age, you may be more likely to have chromosomal abnormalities. Your doctor advises you to think about being tested with Double Marker Reflex to NIPS Test.

Preparation and procedure of the Double Marker Reflex to NIPS Test

There are no precautions to take before, during, or after the NIPS test. It's natural to be nervous until the results arrive, but mothers should try to relax.

Procedure:

A double marker test consists of a blood sample and an ultrasonic examination. The two markers examined in the double marker test are free beta hCG (human chorionic gonadotropin) and PAPP-A- pregnancy-associated plasma protein A. In pregnant women, the placenta secretes a glycoprotein hormone known as free beta-hCG. 

• During this test, your medical practitioner will collect a blood sample to examine for genetic abnormalities in the foetus.
• Every cell of the pregnant lady contains DNA.
• The cells are continuously dividing to produce new cells.
• Little DNA fragments are released into the circulation when cells break down. A small portion of the fetus's DNA circulates in the mother’s bloodstream at the time of pregnancy.
• The NIPS test examines these foetal DNA pieces in the mother’s blood, known as cell-free DNA or cfDNA.
• A blood sample is obtained by your provider through a vein in your arm. This sample is sent to a lab to be analysed. 

It is important to understand that it takes nearly 10 weeks for sufficient foetal DNA to circulate in your blood. As a result, the screening is not done until 10 weeks into the pregnancy.

Understanding of the Double Marker Reflex to NIPS Test Results

The test results will normally arrive as 'low risk as negative' or 'high risk' as positive.

When the results are 'low risk,' the foetus is not likely to have any chromosomal or genetic abnormalities. Down's Syndrome (trisomy 21), Edwards Syndrome (trisomy 18), and Patau Syndrome are the most typically screened conditions with the NIPS (trisomy 13).

A "positive" or "increased/high risk" NIPS test indicates that the infant is at a greater risk of having the anomaly diagnosed.

As discussed above, NIPS is a screening test, not a diagnostic test, thus the baby may not have the problem indicated (false-positive result). Diagnostic testing can be done with either chorionic villus sampling (CVS) between the 10th and 13th week of pregnancy, which collects placental tissue, or amniocentesis (amnio) after around 16 weeks of pregnancy, which samples amniotic fluid.

Your obstetrician may propose other diagnostic testing based on the results of the double marker reflex to NIPT test.