Having a baby is a time for joy and love. But past age 35, women planning to get pregnant or who are already pregnant are wise to be mindful of the genetic risks involved. They should also be aware of, and prepared for, the important step of genetic counseling.
Below is an audio sample of what a genetic counseling appointment should cover between a patient and her obstetrician. The patient is over age 35, pregnant for the first time, and looking for more information on genetic counseling, including the pros and cons of the different tests available, and her prenatal options.
Types of prenatal and genetic testing
The audio clip discusses the three main categories for prenatal and genetic testing:
- Testing for inherited problems like cystic fibrosis and Tay-Sachs disease
- Testing for structural problems like spina bifida and heart defects
- Testing for problems like Down syndrome and chromosome abnormalities
Integrated or combined screening
The most common test available is called integrated or combined screening, which is a combination of one or more blood tests and a special ultrasound. The results are put together to determine how high your risk is for Down syndrome and other common chromosome problems, as well as your risk for spina bifida and chances of premature birth. The ultrasound can evaluate your risk for birth defects and heart defects.
Noninvasive prenatal testing
A newer test, called noninvasive prenatal testing or cell-free DNA testing, is a blood test that produces extremely accurate results for down syndrome, but is less accurate for testing other chromosomal problems that aren’t Down syndrome. It also doesn’t test for spina bifida or heart defects and cannot be used on multiple pregnancies.
Amniotic fluid test
An amniotic fluid test serves as the final word on all possible birth defects and is typically very safe. There is only a small percentage of miscarriage, and most women who have an amniotic fluid test will have zero complications.