How to Read NIPT Test Results for Baby’s Gender: Accuracy, Cost & Timeline
Time to read 10 min
Time to read 10 min
Table of contents
NIPT tests are non-invasive prenatal testing procedures. Prenatal tests play a significant role in pregnancy. The test involves using the pregnant female’s blood to spot congenital abnormalities in the DNA of the fetus. The DNA of the fetus is examined for genetic disorders, including Down syndrome. The NIPT test does not diagnose the conditions; however, it allows healthcare professionals to understand the likelihood of the existence of a condition.
Just by drawing a small amount of blood, NIPT can reveal the gender of the baby and present you with helpful information about the possibility of having a chromosomal disorder. NIPT can disclose the baby's gender by assessing cell-free fetal DNA (cffDNA) in the mother’s blood. It particularly looks for the presence or absence of Y chromosome DNA sequences that are representative of male fetuses.
NIPT is a screening test conducted during pregnancy to examine if the fetus is at risk of having a chromosomal disorder such as Down syndrome, trisomy, and trisomy 13. The test can also tell the fetus’s gender. During the test, a healthcare professional will take your blood sample, which also contains DNA fragments of the fetus. DNA marks up the genes and chromosomes of a person and offers medical professionals a glimpse into the genetic makeup of the fetus. The blood sample is analyzed for particular congenital disorders.
NIPT (noninvasive prenatal testing) is also called cell-free DNA screening because it examines the small amount of DNA that is released from the placenta into the maternal blood. It may not screen for all kinds of genetic or chromosomal conditions. You should be aware that it is a screening test that estimates the possibility of the fetus having a specific condition. It does not diagnose the conditions.
NIPT does not screen for all birth disorders or chromosomal conditions. The screening of sex chromosomes can predict the gender of the fetus and differences in the usual count of sex chromosomes. The test screens for:
NIPT is a simple test procedure that offers significant information. All NIPT panels may not assess for the same conditions. Make sure you talk to your healthcare provider to know and understand your particular NIPT screening.
The mother’s blood is drawn, and the sample is sent to the laboratory for analysis. The test counts the DNA fragments from your placenta that are circulating in your blood so it contains the cells from you as well as your pregnancy. Your cells are consistently dividing and forming new cells. As the cells break down, DNA fragments are released into your bloodstream. These fragments are free-floating, not within the cells, thus also known as cell-free DNA. By inspecting the chromosomes, the doctors can disclose your baby’s possibility of having certain disorders.
Normally, there are two copies of a chromosome. If any of the pairs has an extra chromosome, it is called a trisomy. For instance, Down syndrome is also called trisomy 21, as there is an extra copy of chromosome 21. By examining all chromosomes, NIPT can also tell the sex of your baby. Make sure you tell your healthcare provider whether you want to know the gender of your baby when you get the results. The results usually take a few weeks.
A high-risk result signifies a greater possibility of a chromosomal abnormality, while a low-risk result indicates a lesser possibility. NIPT is a screening procedure, not a diagnostic test, so it would not offer you a yes or no answer bout the fetus having a condition. The result will tell if there is a greater or lower possibility of the fetus having a condition. If the test results suggest a high risk of chromosomal abnormalities, further testing such as chorionic villus sampling or amniocentesis is recommended.
Most laboratories provide separate results for each condition they are investigating. For instance, you may get a high-risk result for trisomy 13 and a low-risk result for Down syndrome. There may be chances that no test results are provided because of inadequate fetal DNA in your blood or the inability to recognize the fetal DNA. In this case, you may be advised to repeat the NIPT test.
NIPT is mostly accurate, but as it is a screening test the result can not demonstrate for sure whether the baby has a chromosomal disorder or not. Screening tests estimate whether your baby is at higher or lower risk of having a certain disorder. A normal NIPT result does not guarantee a healthy fetus, and an abnormal result does not necessarily mean that your baby has a condition.
The NIPT test is very accurate for major conditions, particularly if the results are negative. For instance, when testing for Trisomy 21, the negative test accuracy is 99.5%. If the results are negative, there is less than a 1% chance that your baby has Down syndrome.
It is essential to talk about your NIPT test results with your healthcare provider. It will help you stay informed about the next steps and further testing. If NIPT results signify that the fetus is at risk of having a chromosomal disorder, your doctor may recommend further diagnostic tests to diagnose the conditions:
During the procedure, a small amount of amniotic fluid is withdrawn from the uterus. Amniocentesis can be performed after 15 weeks of pregnancy.
During this test, cells are collected from the placenta, and the sample is analyzed in the lab. The test can be performed between the 10th and 13th week of pregnancy.
NIPT assesses small fragments of fetal DNA available in the mother's bloodstream to screen for chromosomal abnormalities and determine the baby's sex. Typically, the report states the fetal sex as male or female; however, the report may also state the presence or absence of Y chromosome DNA. To read the noninvasive prenatal screening test report look for the sex chromosome or fetal sex section in the report. If the report shows the existence of a Y chromosome, the fetus is likely a male; if there is no Y chromosome, the fetus is likely a female. Usually, the fetal sex determination through the NIPT test is highly accurate, however, there may be a small chance of error, particularly if the test is performed in early pregnancy.
NIPT may not be perfect or accurate in some cases. Talk to your doctor about your test results and essential information. Several factors may influence the accuracy of NIPT test results, such as low fetal fraction (inadequate fetal DNA), maternal conditions (medications and obesity), timing of the test, and presence of multiple gestations.
The most prominent reason for low quality or no result is insufficient fetal DNA in the mother's blood sample.
If the blood sample is collected too early during the pregnancy, there may not be enough fetal DNA present in the mother’s blood.
If the mother is obese, it may lead to a lower fetal fraction in the bloodstream.
If the mother is suffering from certain autoimmune conditions, it may also affect the fetal fraction.
If the mother is taking certain medications, such as blood thinners, these drugs may also affect the fetal fraction in the mother’s bloodstream.
In twin pregnancies or other multiple pregnancies, the fetal fraction can be influenced, leading to no NIPT results.
Maternal age is not directly associated with fetal fraction; however, it is a known risk factor for certain chromosomal abnormalities, and NIPT accuracy may vary depending on the age of the mother.
Maternal cancer can produce DNA fragments in the maternal circulation that can potentially cause discordant NIPT results.
Any kind of errors during the sample collection or processing can contribute to inaccurate results.
Variations in laboratory equipment or procedures can impact the accuracy of NIPT results.
NIPT accuracy for fetal gender prediction is very high in most cases. The sensitivity of this test is 98.9%, and the specificity is 99.6%. The accuracy of the NIPT test increases with gestational age. It can determine the fetal gender with an extremely high degree of accuracy, typically above 99%.
NIPT is highly reliable for fetal sex determination when performed after the 10th week of gestation. The accuracy of fetal gender determination increases with gestational age. In some cases, NIPT may result in inconclusive results in 10-20% of samples. This test can be used to determine fetal gender in twin pregnancies with a predictive model that makes accurate predictions in 97.8% of cases.
The NIPT test may also be used to specify the presence of sex chromosome aneuploidies (SCAs) and order sex development disorders. You need to understand that NIPT is used to detect the chromosomal sex, not precisely gender, which is a psychological identity. The use of NIPT for the sex determination of the fetus raises moral concerns about possible selective pregnancy determination by parents who desire a particular sex of their baby.
The cost of NIPT is not the same everywhere. The exact cost depends on various factors, including where you live, the type of test, the laboratory, and your insurance coverage. Make sure you consult your insurance provider to see if they cover the whole or part of NIPT. Some insurance providers only cover the test cost if the fetus is considered at high risk for having a chromosomal disorder, while others consider it normal prenatal coverage and cover a part of the complete cost.
Typically, you can take the NIPT test anytime after 10 weeks of pregnancy. The NIPT test results, including the sex determination, usually take 3 to 10 days; however, it may also take a few weeks depending on certain factors. Make sure you discuss the test results with your healthcare provider or doctor to understand the exact meaning and if further testing is required.
The NIPT test is an extremely accurate prenatal screening test that evaluates the risk of chromosomal abnormalities in the fetus. The test also gives information about the fetal sex. It does not diagnose conditions but indicates the possibility of a fetus having a particular condition. Prenatal tests are optional and it's completely your choice to take the test or not. If you have any concerns, talk to your healthcare provider.
Make sure you are aware of what the test screens are for and what the results mean so that you can make informed decisions further. Consult your doctor to discuss the benefits, risks whether the test is right for you, and what to expect. Your healthcare provider can help you understand if the test is right for your specific circumstances or not.
The NIPT test can be done after 10 weeks of pregnancy till the delivery. Before the 10 weeks of pregnancy, there may not be sufficient fetal DNA in the blood of a pregnant woman.
Usually, the NIPT tests are accurate; however, the accuracy may vary depending on the conditions it is screening for. Other factors that affect the test accuracy include maternal obesity, insufficient fetal fraction, medications, etc. NIPT is 99% accurate in screening for Down syndrome.
Yes, NIPT can determine the fetal gender.
NIPT tests are usually considered safe, and there is no risk associated with pregnant women and fetuses.
Generally, the NIPT test is more accurate than ultrasound for screening genetic abnormalities.
***Medical Disclaimer: The information provided here is for educational purposes only. No information provided on this website, including text, graphics, and images, is intended as a substitute for professional medical advice. Please consult your healthcare provider concerning your particular medical condition(s).
