First trimester screens and tests

Test	Why it may be offered
Chorionic villus sampling (CVS): A small amount of tissue is removed from your baby's developing placenta under careful ultrasound guidance by a specialized doctor. This is done with a catheter (in your vagina) or a needle (in your abdomen), depending on your placenta's location. Your baby's cells are grown in culture, and the chromosomes are studied. Other DNA or biochemical tests may be done if your history indicates.	To women age 35 or older to check for chromosomal disorders (such as Down syndrome). Or to those identified at risk for specific genetic disorders where a test exists. Typically done at 10 to 12 weeks.
Cultures: They are taken for sexually transmitted diseases.	So you can be treated and your baby will not be at risk.
Cystic fibrosis carrier test: This blood test or cheek swab will determine if you and/or your partner have a single dose of an altered gene for cystic fibrosis. Not all carriers are identified.	To determine if you are at risk for having a baby who will have cystic fibrosis.
Pap smear: A swab collects cervical cells which are then viewed under a microscope.	A regular screening test most women have annually or at the beginning of pregnancy to detect abnormal cells or signs of cervical cancer.
Prenatal profile: Blood is drawn from your arm to screen for blood type, antibody information and diseases.	A test given often to rule out possible complications; given to most pregnant women by their health care providers as a standard screening.
Ultrasound: A transducer that sends sound waves is placed on your abdomen or in your vagina to form a picture of your baby on a screen.	If your dates are uncertain or if you have a high-risk medical condition, this test may be done to measure your baby's growth.

Questions to ask

Ask your health care provider these questions when considering the tests listed on this page:

• What do you hope to learn from this test?
• If the test is positive, what's next?
• If the test is normal, could my baby still have a problem?
• If I am carrying a baby with Down syndrome, what are the chances I will have a normal test?
• If the test is positive, how likely is it my baby has a problem?
• What alternatives are there to having this test?

Related Links

Prenatal screens and tests

Prenatal screenings and tests record (requires Adobe Reader)

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Pregnancy & Parenting eMagazine: Registration

First published: 10/04/2002
Last updated: 06/01/2003

Reviewed by: Allina Patient Education experts