Genetic Testing

There are times during your pregnancy when we recommend for you to be referred to a high-risk obstetric specialist (either at Carolinas Medical Center or through Presbyterian Hospital) for genetic counseling and testing. The conditions for which genetic evaluation are recommended are:

• Age 35 or over
• Abnormal triple screening results (a simple blood test done around 14-18 weeks pregnancy that may detect fetal anomalies)
• Abnormal findings on your routine ultrasound(s)
• A personal or family history of genetic or certain medical problems
• A personal or family history of birth defects

A genetic consultation involves a meeting with a genetics counselor

• For genetic counseling,
• A targeted ultrasound, and
• possibly an amniocentesis or chorionic villus sampling procedure.

You are NOT required to undergo an amniocentesis or chorionic villus sampling if you don't want to.

However, we would strongly recommend genetic counseling and the targeted ultrasound, as these are extremely useful in helping to determine your risks of having an abnormal baby, and they do not carry any risk to you or your baby.

GENETIC COUNSELING

Prior to having any procedure done, you and your partner will meet with a genetics counselor. He/she will sit down with you and go over both your and your partner's personal and family history in detail, particularly any history of genetic or medical problems.

Based on the information obtained, as well as based on your other risk factors such as age and any other abnormal screening results, the genetic counselor and the perinatologist can counsel you appropriately on what your risks of having an abnormal baby are. In addition, it will also help determine what kind of laboratory tests will need to be performed.

Once counseling is completed, if you would still like to proceed, a detailed, targeted ultrasound would then be performed.

TARGETED ULTRASOUND

If you are in your second-trimester, a targeted (Level II) ultrasound is often performed, with or without amniocentesis. Unlike your simple dating ultrasound that is done in our office, a targeted (Level II) ultrasound involves an extremely detailed examination of your baby's anatomy. The perinatologist himself, who is trained to look for fetal anomalies via ultrasound, performs this.

A targeted ultrasound can rule out obvious structural defects in the brain, the spine, the heart, the abdomen, the limbs, etc. Although it is also very good at detecting subtle signs of chromosomal problems, such as Down's syndrome or others, an ultrasound by itself cannot definitively diagnose or rule out the possibility of having a baby with a chromosomal problem. A Level II ultrasound also cannot guarantee that your baby is free of any birth defect.

Having an ultrasound done during pregnancy is safe, and carries no known risk to you or to your baby.