Can You Get Genetic Tests Done While Pregnant?

Key Takeaways

• Genetic testing is optional but can reveal important health information - Jump to Section
• Tests depend on pregnancy stage, with first and second trimester screenings available - Jump to Section
• The tests are generally low-risk, involving ultrasounds or blood samples - Jump to Section
• Testing informs parents about potential inherited conditions - Jump to Section

Pregnancy can be an exciting adventure—but it can also be anxiety-inducing. 

Wondering about the health of your fetus can cause you to worry, but these fears can be easily quieted with genetic testing.

Yes, you can get a genetic test done while pregnant. In fact, it’s highly encouraged to diagnose any risk of congenital conditions or birth defects that you might want to be aware of so you can prepare accordingly.

Understanding any genetic risks that may affect your baby will make it easier to make decisions and will benefit you in the long run. 

Is Genetic Testing Necessary During Pregnancy?

Genetic testing is completely optional.¹

There are plenty of mandatory routine prenatal tests you need to go through to determine the health of your fetus, but genetic testing is not necessarily one of them.

While it’s not a requirement, doctors and genetic counselors encourage getting them.

It is safe and gives you a better picture of what your baby may face health-wise, especially if you or your families have any history of genetic conditions.

You can detect the following in utero:

• Congenital disorders
• Abnormal chromosomal count
• Physical abnormalities
• Diseases you may not have but are carrying in your genes

You should definitely consider genetic testing if you:

• Have a personal or family history of genetic disorders
• Are pregnant and over the age of 35
• Have had miscarriages or stillbirths during previous pregnancies (if any)

When Should I Get a Genetic Test Done When Pregnant?

Genetic screening can differ depending on how far along you are. 

Some genetic tests are only done during certain weeks of pregnancy. Some are carried out early on in the first trimester, while others can only be done with a fetus that’s a little more developed.

First Trimester Screening

During the first few weeks of pregnancy, your doctor may ask you to do preliminary tests to detect any abnormalities that can appear early on. 

Some of these include:

• Nuchal translucency screening – An ultrasound and blood test that measure the amount of fluid in a space at the back of the fetus’s neck. Any abnormal measurements can suggest the presence of Down’s syndrome or other congenital anomalies.
• Cell-free fetal DNA testing – Because some of the baby’s DNA can show up in the mother’s blood, a maternal blood sample is taken and tested for common congenital disorders (like Down syndrome, trisomy-18, trisomy-13, etc.).
• Sequential screening – A tandem ultrasound and blood test to determine the risk of genetic disorders, as well as potential brain or spinal problems. 

Even if the fetus is still in very early development during the first trimester, it’s still wise to seek out any genetic abnormalities. Some of them, like Down syndrome, can be detected as early as ten weeks. 

Second Trimester Screening

During the second trimester, you can get the following done:

• The quad blood test – Shortcut for quadruple blood test, this tests for four different substances in your blood. Any abnormal measurements may suggest congenital abnormalities.
• Second trimester ultrasound – This ultrasound checks for any easily identifiable defects in the brain or spinal development. It also checks facial features, as well as heart and limb development. 
• Amniocentesis – This test is usually performed on women who are at higher risk for passing down genetic disorders. Some amniotic fluid is sampled for any neural tube defects and checked against common congenital abnormalities.

There is also what’s called a combined first and second-trimester screening, where the results of the first trimester tests and second trimester tests are combined to gain more accurate insights and a more holistic snapshot of your baby’s health.⁴

Having these tests done in the same facility or with the same health professionals and genetic counselors will ensure you get the best analyses and advice. 

Getting tests done during the first and second trimesters is ideal. Results may have been inaccurate the first round or new developments may affect results altogether.

How Accurate Are Genetic Tests While Pregnant? 

There are several prenatal screening tests you can take, with many of them being more than 99.9% accurate.² This percentage does vary from test to test, but many of them are accurate more often than not. 

Of course, this is not to say that all these tests are perfect. False positive results can occur, just as they do with other tests.³

While genetic testing can predict the possibilities of these medical conditions, they cannot say with absolute certainty whether or not your baby will contract these diseases.

Genetic tests are able to pinpoint the potential risk of passing on these diseases. It doesn’t mean that your baby will get them, but any positive result will at least give you a chance to prepare accordingly. 

Your genetic counselor or doctor can give you better guidelines and advice depending on the results of your tests. 

Is Prenatal Genetic Testing Safe?

Most prenatal genetic tests are done via ultrasound or blood samples, which generally are very low-risk. 

Other tests, like amniocentesis, require other samples that may not be as easy to obtain. 

As with many medical procedures, even the most common ones, tests aren’t always risk-free. However, collecting blood or buccal samples and carrying out ultrasounds are common practices that aren’t considered risky at all. 

So yes, prenatal genetic testing is safe and has even proven effective in determining the genetic risks your fetus may face.

Why Undergo Prenatal Genetic Testing?

Prenatal genetic screening and carrier screening can help you determine any congenital conditions your baby may inherit.

You can potentially pass on any genetic disorder or congenital abnormality whether you have it, are at risk, or are simply a carrier. Genetic tests are helpful in pinpointing any possibilities for these genetic abnormalities.

Understanding what your baby may inherit can empower you to make decisions around your pregnancy and the lifestyle choices you and your family make.