How’s baby doing? There’s a test for that.
Prenatal tests can give you a good idea of how your baby is developing. Testing can either reassure you that everything is fine, help you prepare for a child with special needs, or alert you to a serious problem. Most babies are born perfectly healthy, and the average pregnancy carries only a 3 to 5 percent risk of a baby with a birth defect.
It’s up to you whether or not you choose to do any prenatal testing. If you do, we have several types of tests available. First, screening tests determine the risk of a certain fetal condition, while diagnostic tests serve to confirm or diagnose the actual condition present.
Swedish offers several screening tests. They require nothing more than a blood draw from you and possibly an ultrasound. These tests pose no risk to mother or baby, and are only done once in your pregnancy.
Screening tests estimate the risk of conditions such as Down syndrome, Trisomy 18 (a serious chromosome condition), and spina bifida. The results will give you an idea of whether further testing is warranted.
If a test were to come back positive, it doesn’t mean there is definitely a problem. It’s only an estimate of the likelihood of a problem. Talking with a genetic counselor will help you understand the results and decide if you should have a diagnostic test.
A diagnostic test can confirm whether or not a certain condition, such as Down syndrome, is present. These tests are offered to women who have had a positive prenatal screening result, are over 35 years of age, have a family history of a genetic condition, or a previous pregnancy involving a birth defect.
Diagnostic tests offered at Swedish include:
- Chorionic villus sampling (CVS) involves taking a small sample of tissue from the placenta to check for chromosomal abnormalities. Using an ultrasound as a guide, your doctor would either go through your abdomen with a long needle, or through your cervix with a small tube. This test does carry a small risk of miscarriage.
- Amniocentesis is the study of amniotic fluid — the doctor uses a long needle guided by an ultrasound to take a small sample. This test can diagnose Down syndrome and other chromosomal abnormalities, spina bifida, anencephaly, and inherited metabolic disorders. This test does carry a small risk of miscarriage, although less so than CVS.
- Fetal echocardiogram checks for problems in a baby’s heart structure or rhythm. It involves an ultrasound that is painless and noninvasive.
- Ultrasounds are common in pregnancy, but are also used to check for specific problems and to measure growth rate and amniotic fluid levels.