Pregnancy and motherhood is a blissful yet complicated journey. An expecting mother has to go through routine checkups and test to know the growth status of the baby. However, at times, due to genetic complications or chromosomal abnormalities, the chance of recurring pregnancy loss or giving birth to a baby with genetic syndrome increases.
This makes it crucial and highly recommended to take a prenatal screening for the presence of any sort of chromosomal aberrations in the growing fetus. For women suffering from recurrent miscarriages, going through a genetic screening before pregnancy is quite helpful to analyze potential risks and complications.
Importance of Prenatal Genetic Test and Screening
Prenatal genetic screening help in screening for chromosomal abnormality or genetic aberrations in the fetus. It is highly recommended for women above the age of 35 years or with a family history of genetic conditions. The purpose of the prenatal screening test is to find the probability of a baby being born with genetic disorders.
It is not a diagnostic technique but a screening method that helps the parents and expecting mothers to make an informed decision. The best time for genetic screening is from the 10th to the 13th week during the first trimester where the analysis is done by extracting blood from the mother. It is a crucial early detection screening technique for finding out the probability of genetic disorders and chromosomal abnormalities.
Different Types of Prenatal Genetic Screening Test
The prenatal screening for genetic disorders are of different types and it can be done as early as within the 10th to 13th week during the 1st trimester.
- Maternal Blood Sample – This is a type of NIPT genetic screening where the blood from the mother is extracted and the cfDNA from maternal blood is analyzed. In this technique, the cfDNA (cell-free DNA) from developing fetus circulated in the maternal blood is analyzed to check for aneuploidy like Trisomy 21 (Down Syndrome), Trisomy 18 (Edward’s Syndrome), Trisomy 13(Patau’s Syndrome) or aneuploidy in sex chromosomes.
- Ultrasound Exam – This is also called Nuchal Translucency Screening which measures the thickness of space at the fetus’s back. A negative or abnormal result helps in detecting aneuploidy, majorly Down Syndrome.
- The Quadruple blood test is done during 2nd trimester and it screens for genetic aneuploidy like Down Syndrome, Edwards Syndrome etc. It is majorly done between 15 to 22 weeks of pregnancy.
The test results are mostly 99% accurate for Down Syndrome. The positive screening test result indicates the fetus is at higher risk of being born with a genetic disorder. However, it cannot 100% ascertain and assure that fetus will be born with the disorder. The negative screening test indicates no or low chances of the fetus being born with a genetic disorder.
In case of positive results for the screening test, the next step is to consult a professional genetic counsellor to take further steps after a complete and thorough examination and diagnosis. Doctors often recommend NIPT prenatal genetic screening test early during pregnancy but it does not necessarily mean that there is some defect.
Where to Take the Genetic Screening Tests?
The genetic screening tests before pregnancy as well as during pregnancy can be performed at state-of-the-art infrastructure molecular diagnostic labs. The next-generation sequencing technology helps in conducting an in-depth analysis of genetic aneuploidy in the growing fetus. The test helps in analysing genetic abnormality in the expecting mother to analyze the complications or risks associated with pregnancy.
It is highly recommended for women who have suffered miscarriages in the past. The advanced labs provide pre and post-test genetic counselling to understand the process completely and take the right decision.
Early genetic screening is the best intervention to prevent genetic disorders in a growing fetus. In this case of 100% genetic disorder detection, it gives chance to the parents to make the right decision.
