Prenatal Tests: FAQs

What Are Prenatal Tests?

Prenatal tests are screening or diagnostic tests that can help identify health problems that could affect pregnant women or their unborn babies. Some of these conditions can be treated, so it's important to find them as soon as possible.

Why Are Prenatal Tests Done?

Prenatal tests are given in the first, second, and third trimesters. In a mother, they can determine key things about her health that can affect her baby's health, such as:

her blood type
whether she has gestational diabetes, anemia, or other health conditions
her immunity to some 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
show characteristics of the baby, including size, sex, age, and position in the uterus
help determine whether a baby might have a birth defect, genetic problem, or other condition

Some prenatal tests are screening tests that can only reveal the possibility of a problem. Other prenatal tests are diagnostic tests that can accurately find whether a fetus has a specific problem. A screening test sometimes is followed by a diagnostic test.

Although your health care provider (who may be your OB-GYN, family doctor, or a certified nurse-midwife) may recommend these tests, it's up to you to decide whether to have them.

Who Should Have Prenatal Tests?

Some prenatal tests are considered routine — that is, almost all pregnant women receiving prenatal care get them. They include things like checking urine (pee) levels for protein, sugar, or signs of infection.

Other non-routine tests are recommended only for some women, especially those with high-risk pregnancies. These may include women who:

are age 35 or older
are teens
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, an STD, asthma, or a seizure disorder
have an ethnic background in which genetic disorders are common (or a partner who does)

What Else Should I Know?

Remember that tests are offered to you — it's your choice whether to have them.

To decide which tests are right for you, talk with your health care provider about why a test is recommended, its risks and benefits, and what the results can — and can't — tell you.

Questions to ask: