FAQs: Prenatal Tests
Every parent-to-be hopes for a healthy baby, but it can be hard not to worry: What if the baby has a serious or untreatable health problem? What would I do? Is there anything I can do to prevent problems?
Concerns like these are completely natural. Fortunately, a wide array of tests for pregnant women can help reassure them and keep them informed throughout their pregnancies.
What Do Prenatal Tests Find?
Prenatal tests can help identify health problems that could endanger both a woman and her unborn child, some of which are treatable. However, these tests do have limitations. As an expectant parent, it’s important to educate yourself about them and to think about what you would do if a health problem was detected in either you or your baby.
- her blood type
- whether she has gestational diabetes, anemia, or other health conditions
- her immunity to certain diseases
- whether she has a sexually transmitted disease (STD) or cervical cancer
In a developing child, prenatal tests can identify:
- treatable health problems that can affect the baby’s health
- characteristics of the baby, including size, sex, age, and placement in the uterus
- the chance that a baby has certain birth defects or genetic problems
- certain types of fetal abnormalities, like heart problems
The last two items on this list may seem the same, but there’s a key difference. Some prenatal tests are screening tests and only reveal the possibility of a problem. Other prenatal tests are diagnostic, which means that they can determine — with a fair degree of certainty — whether a fetus has a specific problem. In the interest of making the more specific determination, the screening test may be followed by a diagnostic test.
Who Gets Prenatal Tests?
Certain prenatal tests are considered routine — that is, almost all pregnant women receiving prenatal care get them. They include things like checking urine levels for protein, sugar, or signs of infection.
- are age 35 or older
- are adolescents
- have had a premature baby
- have had a baby with a birth defect — especially heart or genetic problems
- are carrying more than one baby
- have high blood pressure, diabetes, lupus, heart disease, kidney problems, cancer, a sexually transmitted disease, asthma, or a seizure disorder
- have an ethnic background in which genetic disorders are common (or a partner who does)
- have a family history of mental retardation (or a partner who does)
Although your health care provider (who may be your OB-GYN, family doctor, or a certified nurse-midwife) may recommend these tests, it’s ultimately up to you to decide whether to have them.
Also, if you or your partner have a family history of genetic problems, you may want to consult with a genetic counselor to help you look at the history of problems in your family and to determine the risk to your children.
To decide which tests are right for you, it’s important to carefully discuss with your health care provider:
- what these tests are supposed to measure
- how reliable they are
- the potential risks
- your options and plans if the results indicate a disorder or defect
Where Can I Get More Information?
Some prenatal tests can be stressful, and because many aren’t definitive, even a negative result may not completely relieve any anxiety you might be experiencing. Because many women who have abnormal tests end up having healthy babies and because some of the problems that are detected can’t be treated, some women decide not to have some of the tests.
One important thing to consider is what you’ll do in the event that a birth defect or chromosomal abnormality is discovered. Your health care provider or a genetic counselor can help you establish priorities, give you the facts, and discuss your options.
It’s also important to remember that tests are offered to women — they are not mandatory. You should feel free to ask your health care provider why he or she is ordering a certain test, what the risks and benefits are, and, most important, what the results will — and won’t — tell you.
If you think that your health care provider isn’t answering your questions adequately, you should say so. Things you might want to ask include:
- How accurate is this test?
- What are you looking to get from these test results? What do you hope to learn?
- How long before I get the results?
- Is the procedure painful?
- Is the procedure dangerous to me or the fetus?
- Do the potential benefits outweigh the risks?
- What could happen if I don’t undergo this test?
- How much will the test cost?
- Will the test be covered by insurance?
- What do I need to do to prepare?
You also can ask your health care provider for literature about each type of test.
How Can I Give My Baby a Good Start?
The best way for mothers-to-be to avoid birth defects and problems with the pregnancy is to take precautions, such as:
- not smoking (and avoiding secondhand smoke)
- avoiding alcohol and other drugs
- checking with the doctor about the safety of prescription and over-the-counter medications
- avoiding fumes, chemicals, radiation, and excessive heat
- eating a healthy diet
- taking prenatal vitamins — if possible, even before becoming pregnant
- getting exercise (after discussing it with the doctor)
- getting plenty of rest
- getting prenatal care — if possible, beginning with a preconception visit to the doctor to see if anything needs to change before you get pregnant
Reviewed by: Elana Pearl Ben-Joseph, MD
Date reviewed: June 2013