Prenatal testing: Is it right for you?

Prenatal testing can provide valuable information about your baby's health. Understand the risks and benefits, and how prenatal testing might affect prenatal care. By Mayo Clinic Staff

Pregnancy is a time of great anticipation — and anxiety.

You might be wondering if you'll experience complications or if your baby will have health problems. Take comfort in the fact that most babies are born healthy. Still, you might want details about your baby's health beyond what your health care provider can observe.

Enter prenatal testing.

Types of prenatal testing

Prenatal testing includes both screening tests and diagnostic tests:

  • Screening tests. Prenatal screening tests can identify whether your baby is more likely to have certain conditions — but they usually can't make a definitive diagnosis. General screening tests, such as blood tests and ultrasounds, are routine in most pregnancies. Specific screening tests, such as first and second trimester screening for abnormal chromosomes, also might be offered. Screening tests pose no risks for mother or baby.
  • Diagnostic tests. If a screening test indicates a possible problem — or your age, family history or medical history puts you at increased risk of having a baby with a genetic problem — you might consider a more invasive prenatal diagnostic test. A diagnostic test is the only way to be sure of a diagnosis. Some diagnostic tests, such as chorionic villus sampling or amniocentesis, carry a slight risk of miscarriage.

Despite these clear definitions, recent changes in technology have blurred the line between traditional screening and diagnostic tests.

For example, a new blood test for Down syndrome is now available in some areas. The test analyzes fetal DNA circulating in a mother's bloodstream. If a traditional screening test indicates a high risk of Down syndrome, the new blood test can define the risk more clearly. Although it isn't considered a diagnostic test, a normal result might eliminate the need for more invasive diagnostic testing.

Aug. 14, 2012 See more In-depth