Non-invasive prenatal testing (NIPT) is a screening method that assesses the likelihood of a fetus having genetic abnormalities or chromosomal disorders. While NIPT can determine whether there is a high or low risk for these conditions, it is not a diagnostic test. Changes in the structure of chromosomes, such as missing or duplicated segments, can be detected. NIPT screens for chromosomal disorders like Down syndrome, Turner syndrome, Edward syndrome, and Patau syndrome.

NIPT screens for abnormalities in the X and Y sex chromosomes. It also identifies genetic conditions such as Edward syndrome (trisomy 18), Patau syndrome (trisomy 13), and Down syndrome (trisomy 21), all of which result from an extra chromosome.

A blood sample from the mother is used to assess the risk of genetic abnormalities. The results of NIPT are often compared with other tests, such as a first-trimester ultrasound or nuchal translucency screening, to determine if further testing is required.

NIPT is recommended for pregnancies considered high risk, including women over 35 years of age, those with a history of chromosomal disorders, a positive serum screen, or an abnormal fetal ultrasound.

NIPT is approximately 99% accurate. However, a diagnostic test such as amniocentesis is usually recommended for more conclusive results. While NIPT is highly reliable, there is a minimal chance of false positives or negatives.

NIPT can be conducted anytime after 9 to 10 weeks of pregnancy. It is commonly chosen by women over the age of 35, or by parents with a family history of genetic disorders. If a traditional screening test shows a high risk, many opt for NIPT for further assessment.

NIPT analyzes cell-free DNA found in the mother’s blood, which includes fetal DNA. The plasma is separated from the blood, and the cell-free DNA is examined for any genetic abnormalities like Down syndrome, Edward syndrome, or Patau syndrome. Advanced analysis is then performed on the extracted DNA to provide results.

NIPT is generally advised for women at higher risk of chromosomal disorders. This non-invasive procedure only requires a blood sample and provides quick results, helping parents prepare for further steps if necessary.

NIPT cannot detect all genetic disorders and is less effective in pregnancies with multiple fetuses. For complete accuracy, additional tests like amniocentesis or chorionic villus sampling (CVS) are often necessary. The test has also raised ethical concerns, particularly around the increased rates of pregnancy terminations following a Down syndrome diagnosis.

One of the main benefits of NIPT is that it poses no risk to the mother or fetus, as it only involves drawing a blood sample. It provides fast and reliable results, generally available within 10-14 days, allowing parents to make informed decisions early in pregnancy.

However, NIPT is not a replacement for diagnostic tests. Although it has proven accurate for both high- and low-risk pregnancies, diagnostic procedures like amniocentesis are still recommended for a definitive diagnosis.