Prenatal Testing
Prenatal testing provides information about your baby's health before he or she is born. Testing is available to pregnant women
- Who are aged 35 or older, because they are at higher risk for having a child with a chromosomal abnormality
- Who have a family history of an inherited condition such as Duchenne muscular dystrophy
- When their ancestry or ethnic background means that they might have a higher chance of an inherited disorder such as sickle cell anemia, thalassemia or Tay-Sachs disease
- To screen for common genetic disorders such as spina bifida and Down syndrome
Two diagnostic procedures are common in prenatal testing. Amniocentesis involves testing a sample of amniotic fluid from the womb. CVS (or chorionic villus sampling) involves taking a tiny tissue sample from outside the sac where the fetus grows.
Prenatal testing: Who should consider it?
Pregnancy is a time of great anticipation. Will you have a girl or a boy? Will the baby inherit your sense of humor or your partner's compassion? You may have moments of doubt and anxiety as well. Will you experience complications? Will the baby be healthy?
Take comfort in the fact that most babies are born healthy. Still, you may want details about your baby's health beyond what your health care provider can observe. Enter prenatal testing.
Types of prenatal testing
Blood tests and imaging studies to screen for common conditions are routine in most pregnancies. These tests can identify whether your baby is more likely to have certain conditions — but they can't make a definitive diagnosis. Simple screening tests don't pose risks for you or your baby.
Some serious conditions can only be detected using specialized prenatal tests. If a screening test indicates a possible problem — or your age or family history puts you at increased risk of having a baby with a genetic problem — you may consider more invasive diagnostic testing.
Questions to consider
Prenatal testing is optional. It's important to make an informed decision — especially if you're screening for fetal conditions that can't be treated.
- What will you do with the test results? Normal results can ease your anxiety. But if prenatal testing indicates that your baby may have a birth defect, you may be faced with wrenching decisions — such as whether to continue the pregnancy. Or you may welcome the opportunity to plan for your baby's care in advance.
- Will the information shape your prenatal care? Most routine prenatal tests are intended to detect problems that can be treated while you're pregnant. Sometimes prenatal testing may alert your health care provider to a problem that requires immediate treatment after birth.
- How accurate are the results? Prenatal testing isn't perfect. The proportion of false-negative and false-positive results varies from test to test.
- What are the risks? Weigh the risks of specific prenatal tests — such as anxiety, pain or possible miscarriage — against the value of knowing the results.
