Can Nipt Test Be Wrong For Gender

Every mom-to-be eagerly awaits the moment when they can find out the sex of their baby. In today’s era of advanced technology, this exciting news can often be revealed earlier than ever before thanks to Non-Invasive Prenatal Testing (NIPT).

This optional blood test analyzes DNA, specifically looking for chromosomal abnormalities, and can also determine a baby’s sex. But is it foolproof? Can the NIPT test be wrong for gender?

Understanding NIPT: Cell-Free DNA Testing involving a Blood test


What is NIPT?

Non-Invasive Prenatal Testing, or NIPT, is a method of screening that checks for specific chromosomal abnormalities in a baby’s DNA. It works by analyzing fragments of your baby’s DNA, or cell-free DNA, floating around in the mom’s bloodstream.

This test is typically administered during the first trimester of pregnancy, as early as the 10th week of the baby’s amazing development track.

How does it work?

The NIPT test involves a simple blood draw from the pregnant woman. This blood sample contains bits of the baby’s DNA (fetal DNA) along with the mother’s. These tiny fragments are what the test analyzes, looking for any signs of chromosomal abnormalities such as Down Syndrome.

Why it is Important?

NIPT is significant due to its high accuracy rate and its ability to detect potential health concerns early in pregnancy. It is non-invasive and poses no risk to the baby or mother, making it a preferred choice over some other diagnostic tests.

NIPT and Gender Determination


How NIPT Determines Gender

In addition to checking for chromosomal abnormalities, NIPT can also help determine the sex of the baby. This is possible because the presence (or absence) of the Y chromosome detected in the mum-to-be’s blood indicates the child’s sex. If a Y chromosome is present, the baby is likely to be a boy, and if it’s not, the baby is likely a girl.

Significance of Y Chromosome

The Y chromosome is what differentiates males from females at the genetic level. If the fetal DNA in the blood sample contains a Y chromosome, it indicates that the baby is a boy. However, its absence suggests the baby is a girl since females have two X chromosomes.

Accuracy of NIPT


Is NIPT Always Right?

While NIPT is typically very accurate, it isn’t flawless. The primary purpose of NIPT is to screen for chromosomal abnormalities, with sex determination being a secondary benefit. Hence, there is a small chance that the NIPT test could be wrong about the gender.

Reasons for Wrong NIPT Results


Biological Reasons

Occasionally, the test might detect a Y chromosome when there isn’t one, or it might fail to detect a Y chromosome that is present. This could happen due to various biological reasons, such as having a very low fetal fraction (the amount of fetal DNA in the mother’s blood).

Technical Errors

In addition to biological reasons, technical errors in the lab could also lead to wrong NIPT results. These could include mix-ups with samples or issues during the DNA analysis process.

NIPT vs Ultrasound

While NIPT testing can be done early in the first trimester, a gender scan or ultrasound for sex determination is typically done around the mid-second trimester when the baby’s genitals are more visibly developed.

Both have a high degree of accuracy to identify boy parts or girl parts, but ultrasound depends significantly on the baby’s position and the experience of the ultrasound technician.

Steps of NIPT


Blood Work

The NIPT process begins with a simple blood draw. This blood work is then sent off to a lab for analysis.

Analyzing DNA

In the lab, the blood sample is processed to extract the cell-free DNA. The test then analyzes this DNA, looking specifically for the presence of certain chromosomes.

Result Interpretation

Once the DNA analysis is complete, the results are interpreted. If a Y chromosome is detected, the NIPT result would suggest a boy, and if not, it suggests a girl.

Possible Misinterpretations


Wrong Gender

While rare, there can be cases of NIPT showing the wrong gender. As mentioned before, this could be due to biological factors or technical errors.

Confusing Test Results

Sometimes, the test results can be ambiguous. For example, if the fetal fraction is too low, it might not provide a clear result, which could lead to confusion.

Consequences of Wrong Gender Determination


Emotional Impact

A wrong gender result can be emotionally upsetting for parents who may have already started bonding with their baby of a particular sex.

Planning Challenges

Parents often start planning for their child’s nursery, clothes, and other necessities based on gender. A wrong gender result can disrupt these preparations, leading to additional stress.

What to Do if NIPT is Wrong?


Consultation with OB-GYN

If you suspect your NIPT test could be wrong, the first step is to consult with your OB-GYN. They can help you understand the test results better and guide you on the next steps.

Follow-up Diagnostic Tests

Your doctor might suggest follow-up diagnostic tests, such as an ultrasound or amniocentesis, to confirm the baby’s gender and rule out any potential chromosomal abnormalities.

Reliability of NIPT


Statistics and Studies

While instances of wrong gender determination via NIPT do occur, they are relatively rare. Studies suggest that NIPT has a 99% accuracy rate for Down Syndrome detection and approximately 98% accuracy for sex determination, making it a reliable screening method for most pregnancies.


The prospect of knowing your baby’s gender early on in pregnancy can be exciting. But it’s essential to remember that while NIPT is an advanced, reliable technology, it’s not infallible. Understanding its limitations can help manage expectations and prepare for any surprises along the way. But rest assured, the journey of tracking your baby’s amazing development remains as thrilling, regardless of the initial NIPT test results.



Can NIPT test be wrong for gender?

While NIPT is highly accurate, there is a small chance that the gender prediction can be wrong due to various reasons such as low fetal fraction or technical errors.

What should I do if I think my NIPT result is wrong?

If you suspect your NIPT result could be incorrect, consult with your OB-GYN. They can advise on the next steps, which might include additional diagnostic tests.

Is NIPT more accurate than ultrasound for gender determination?

NIPT and ultrasound both have a high degree of accuracy for gender determination. However, NIPT can be conducted earlier in the pregnancy compared to an ultrasound gender scan.

What is the primary purpose of NIPT?

The primary purpose of NIPT is to screen for specific chromosomal abnormalities, such as Down Syndrome, not sex determination.

How early can NIPT be done in pregnancy?

NIPT can typically be administered as early as the 10th week of pregnancy.





This post is written and edited by Sandy who is a clinical pharmacist with over 20 years of experience specializing in pre-natal and post-natal care.