Children's Hospital Colorado

Prenatal Genetic Testing and Screening

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Every parent wants to have a healthy child. At the Colorado Fetal Care Center, we’re here to help you understand, plan for and make decisions about your pregnancy. Children’s Hospital Colorado’s genetic counselors can help you find answers and ensure the best outcome possible for your family.

Whether you’ve been diagnosed with a high-risk pregnancy or you’d like to learn more about the chances of passing down a genetic condition, our hospital in Aurora, Colorado offers complete and thorough genetic testing for parents, mothers and babies.

What are the chances of having a baby with a birth defect or genetic syndrome?

Every pregnancy has a 3% to 5% risk of identifying a birth defect or genetic condition. Though there is a small chance for every baby to have a genetic condition, some pregnancies have a higher risk than others. Advanced maternal age (a mom who is age 35 and older) and a family history of birth defects or genetic conditions are two reasons a pregnancy may be considered high risk. In this case, your doctor may recommend genetic screening or diagnostic testing.

While there’s no test that can guarantee a healthy baby, some genetic tests can provide additional information and reassurance for families during pregnancy.

What are the types of prenatal genetic tests?

There are two types of genetic tests: screening tests and diagnostic tests. Each provides different information about the pregnancy and the risk that the baby will inherit or develop certain conditions or chromosomal abnormalities.

What is the difference between prenatal genetic screening and prenatal diagnostic testing?

Though these terms are often used interchangeably, they are performed differently and provide different details about the pregnancy.

Screening tests

  • Screening tests provide additional information about whether a pregnancy is at higher or lower risk for certain conditions, but they do not provide a definitive yes or no answer.
  • Screening tests are typically non-invasive and do not pose a risk to the pregnancy. They usually involve blood draws or ultrasounds.
  • Screens are not comprehensive, meaning that they provide risk information for a small number of common genetic conditions, such as Down syndrome (trisomy 21), Edwards syndrome (trisomy 18) and Patau syndrome (trisomy 13).

Diagnostic tests

  • Diagnostic tests provide a definitive yes or no answer about whether a baby has a chromosomal abnormality or certain genetic conditions.
  • Diagnostic tests are invasive and carry a small risk (less than 1%) for miscarriage.
  • These tests can detect a much larger number of genetic conditions and rarer conditions than a screen.
  • The information from a diagnostic test may help you and your providers determine the best monitoring and care for you and your baby during pregnancy and after delivery.

As with any pregnancy, the choice to pursue genetic screening or testing is a personal decision based on your values and goals. Our experts will answer your questions so you can make an informed decision. We will support any decision you make, including electing not to pursue screening or testing.

Learn more about what to expect from genetic testing in this video:


Types of prenatal genetic screening tests

We use multiple types of genetic screens in the prenatal period. Expand the windows below to learn about each test.

Types of prenatal genetic diagnostic tests

There are two types of diagnostic tests a mother can receive during pregnancy: chorionic villus sampling (CVS) or amniocentesis. These invasive prenatal tests can help doctors determine the health of a baby while they’re in utero (in the womb).

What’s the difference between CVS and amniocentesis?

Though both CVS and amniocentesis are used to diagnose genetic conditions and birth defects, these procedures are performed differently and at different times during pregnancy.

CVS allows doctors to diagnose:

  • Chromosome problems
  • Specific genetic conditions

Amniocentesis (or amnio, for short) allows doctors to diagnose:

  • Chromosome problems
  • Specific genetic conditions
  • Viral infections

Is CVS or amniocentesis safer?

Both CVS and amniocentesis present a low risk of miscarriage at less than 1%. Statistically speaking, the chances of miscarriage are higher with CVS (1 in 400 chances) than with amniocentesis (1 in 900 chances).

There are benefits and limitations to each test. Expand the windows below to learn about these procedures and what to expect.

After prenatal genetic testing

No matter what screening or genetic testing results may show, our team at Children’s Colorado is available to guide you and your family throughout your pregnancy. We’ve helped hundreds of women and couples find hope – and exceptional care – for their babies, even in the face of rare genetic syndromes or other prenatal diagnoses. In fact, we see so many babies with rare conditions that here, the rare is common.

Learn more about the conditions we treat or find out more about our fetal medicine specialists.

Contact us

We’re here to help. If you have questions about prenatal genetic testing and resources available for you and your baby, please call the Colorado Fetal Care Center at 1-720-777-4463.

Here, rare is common.

At Children’s Colorado, our Neonatal Intensive Care Unit is equipped to care for any condition that affects newborns, regardless of how rare or critical. Our highly specialized neonatology services give thousands of infants a healthy start – year after year.

Learn about our nationally ranked NICU

Would you like a second opinion?

If you have received a prenatal diagnosis, are considering treatment options or just want to feel more confident about your treatment plan, our fetal care experts are here to help.

Request a second opinion from our Colorado Fetal Care Center