Ask Our Staff: Positive Genetic Testing

Dear Tracy:

I have an appointment with a genetic counselor to see if my baby is at risk for a birth defect. If I test positive, does that automatically mean she will be born with an abnormality?

Birth defects affect one in every 33 babies born in the United States each year. Common birth defects can happen because of:

• Conditions passed down from parent to baby
• Certain infections or environmental exposures to you during pregnancy
• Changes in your baby’s chromosomes or genes, known as genetic abnormalities
• Structural defects with your baby

During your visit, we’ll perform screening tests by drawing your blood to look for certain substances. We’ll also do an ultrasound to look at internal structures of your baby. These tests help show the chance your baby could test positive for a birth defect. They can’t tell for sure if a problem will happen. A positive result means your baby is more likely to have a birth defect. If you test negative, your baby is less likely to have a defect. It doesn’t guarantee a normal pregnancy or baby.

What if you or your baby test positive?

If you or your baby test positively, we’ll recommend diagnostic testing. This will provide a yes or no answer about chromosome problems in your baby. We gather cells for genetic testing either through a blood sample, from tissues around your baby (chorionic villus sampling), or from the amniotic fluid (amniocentesis).

If a specific birth defect is detected with your baby, we’ll connect you with resources and information to care for your baby.

You can read about what genetic testing actually does, here. Here is what you can expect during your first genetic counseling appointment. For more information about genetic testing and birth defects, click here.

Who should consider genetic testing?

Although anyone can receive genetic counseling and testing, we highly recommend it for:

• Women older than 35 who are pregnant or planning to become pregnant
• Certain ethnicities or couples with increased risk
• Couples who have a child with a birth defect
• Couples who’ve had miscarriages

Speak with a Genetic Counselor

If you are interested in speaking with one of our certified genetic counselors like Tracy Dawson, MS, CGC, please call (865) 331-2020 for an appointment.

Depending on your insurance, you may need a referral from your primary care physician for genetic counseling to be a covered benefit.

Before you schedule an appointment, it is helpful to gather as much information as possible about the issues that are concerning you. We suggest you talk with family members and request medical records. If you have any questions about what you should have ready for your appointment, please call us at (865) 331-2020.

Disclaimer: please note that this information is for educational purposes only and is not intended to serve as medical advice. If you have a specific medical question or issue, we encourage you to call our office at (865) 331-2020 and schedule an appointment.