What Is the Non-Invasive Prenatal Test?
A particularly reliable screening tool is the non-invasive prenatal test (NIPT). To determine whether the unborn child has a high risk of developing a genetic health issue, screening tests are performed. These disorders include various chromosomal abnormalities and Down syndrome. A straightforward blood test known as the NIPT is administered during the first trimester of pregnancy. Various prenatal tests are available to assess the unborn child's health. A portion of the baby's DNA enters the bloodstream during pregnancy. The non-invasive prenatal test examines the genetic data present in this DNA. It is employed as a screening tool for certain genetic disorders. The test has a high sensitivity to Down syndrome.
What Does a Non-invasive Prenatal Test For?
An excellent and safe method of screening for specific conditions is the NIPT. Among these are:
1. Trisomy 21 or Down Syndrome
A person with Down syndrome possesses an extra chromosome or a portion of a chromosome. The development of a baby's body and brain is altered by this additional copy. Throughout their lifespan, it may provide both physical and mental difficulties. In the United States, the most prevalent chromosome-related illness is Down syndrome. The ages of the parents at birth are risk factors for Down syndrome. The likelihood of having a child diagnosed with Down syndrome or another genetic disease is higher in women or people designated female at birth (AFAB) who are 35 years of age or older.
2. Trisomy 18 or Edwards Syndrome
A genetic disorder called Edwards syndrome (trisomy 18) results in physical growth deficits in fetuses. Those who have trisomy 18 frequently have low birth weights and delayed prenatal growth (intrauterine growth retardation). Affected people may have anomalies in other organs, like the heart, that develop before birth. Trisomy 18 also presents with a small, malformed skull, a small mouth and jaw, and clenched fists with overlapping fingers. Many people with trisomy 18 pass away before birth or within the first month of life due to several potentially fatal medical conditions.
3. Trisomy 13 in Patau Syndrome and Turner Syndrome
A second copy of chromosome 13 exists in some or all of the body's cells, which results in the serious, uncommon genetic condition known as Patau's syndrome. Trisomy 13 is another name for it. Along with physical growth irregularities across a child's body, trisomy 13 impairs the development of the face, brain, and heart. Trisomy 13 can have potentially fatal symptoms and increase the risk of miscarriage or death before the child reaches one year old. Offspring born to parents over the age of 35 have a higher incidence of this condition. Physical growth defects such as a tiny head, cleft palate, extra fingers or toes, and low muscle tone are caused by trisomy 13.
Additionally, the disease may impact the child's internal organ development, potentially resulting in life-threatening symptoms. Turner syndrome is a disorder that primarily affects females and is caused by the partial or complete loss of one X chromosome. Several medical and developmental issues, such as heart malformations, failure of the ovaries to mature, and short stature, can be brought on by Turner syndrome. It is possible to diagnose Turner syndrome before birth, soon after delivery, or in the early years of life. Turner syndrome has no known treatment. However, some drugs and treatments can help control its symptoms.
Certain labs additionally assess the baby's sex and search for variations in the sex chromosomes. The test finds numerous chromosomal abnormalities.
It is not able to check for hereditary illnesses like:
- Thalassemic cystic fibrosis.
- Anemia with sickle cells.
Why Is Non-invasive Prenatal Testing Done?
Prenatal testing that is noninvasive aids in assessing the fetus's risk of having specific chromosomal abnormalities at birth.
If one exists, medical professionals might suggest the following:
- Child with genetic disorder.
- Possess an ultrasound that suggests the fetus might have an anomaly.
- Own a history of screening tests that point to a possible issue.
- Only pregnant women deemed high risk are advised to undergo NIPT by the American College of Obstetricians and Gynecologists (ACOG). Regardless of the risk, healthcare professionals are advised to deliver NIPT to all expectant patients.
When Should the NIPT Test Be Done During Pregnancy?
NIPT testing can begin as early as week ten of pregnancy and continue until birth. Before ten weeks of pregnancy, there is usually not enough fetal DNA in a pregnant person's blood.
How Accurate Are NIPT Tests?
Depending on the condition, the test's accuracy varied. Additional variables that may impact the results of an NIPT include obesity, surrogacy, and multiple pregnancies. When it comes to identifying Down syndrome, NIPT is almost 99 percent accurate. Trisomy 18 and 13 can be detected using the test with slightly less accuracy. Comparing NIPT tests to other prenatal screens, like the quad screen, yields fewer false positives overall.
Conclusion:
The technique used to determine whether a fetus has chromosomal problems or genetic abnormalities is called non-invasive prenatal testing, or NIPT. Only the high and low risks of a genetic disease can be detected by NIPT. A simple blood test is done using the mother's blood to identify any abnormalities. Pregnant women at high risk are recommended to get NIPT.
Women who have already experienced an affected pregnancy, are over 35 years old or have an uncommon fetal ultrasound finding, which is considered high-risk. Since less than 1 percent of newborns are affected by the illness, the results are typically 99 percent correct. NIPT is strongly advised in conjunction with a diagnostic test like amniocentesis for a reliable result. Compared to conventional screening tests, the NIPT is more reliable.
