Genetic Testing Options

The First Trimester Screen

Screening is available for some of the more common genetic syndromes: Down syndrome and two others known as Trisomy 13 and Trisomy 18. This screening is not required; it is done at your request and can detect a variety of rare birth defects.

This test does not diagnose these conditions. Rather, it lets you know whether your pregnancy is at increased or decreased risk for these conditions. Women who screen at increased risk may choose to have further, definitive testing.

The test is a combination of an ultrasound and a blood test obtained through a finger prick between 11 and 13 weeks of pregnancy. While it is the most accurate test available, it is not perfect and will miss some affected babies as well as cause other women with normal babies to worry unnecessarily.

Screening for Cystic Fibrosis

Another optional test screens for cystic fibrosis carriers. Cystic fibrosis is a serious medical condition affecting the lungs and the intestinal tract. Both parents must be carriers for a baby to inherit the disease.

There is a blood test that detects 30 to 97 percent of carriers of cystic fibrosis (depending on your ethnic background). This test can be run on your blood. If you were found to be a carrier, it would be important to test the father of the baby. If you were both found to be carriers, the chance of your baby having cystic fibrosis would be 25 percent.

Other Genetic Testing

Certain ethnic groups are at increased risk of certain genetic conditions. For example, African-Americans are at increased risk for sickle cell anemia; people of Ashkenazi Jewish descent are at increased risk for Tay-Sachs and other metabolic diseases; the Caucasian population has a higher risk for cystic fibrosis.

Other genetic conditions may run in your family. Please let us know if there are genetic issues of concern to you and your family.