Prenatal Genetic Testing Chart

These tests can tell you the chances that your fetus will have certain genetic disorders.

[Tests are displayed on a graph according to their recommended timing during pregnancy.]

Carrier Testing

• Timing: Can be done at any time but is ideally performed before pregnancy
• Tests use blood or tissue sample (tissue from inside the cheek)
• Detects whether you, your partner, or both carry a mutation in a gene for a certain genetic disorder

First-trimester Screening

• Timing: 10–13 weeks
• Blood test plus NT ultrasound exam
• Screens for Down syndrome and trisomy 18

Integrated Screening and Sequential Screening

• Timing: 10–22 weeks
• Combines first-trimester and second-trimester screening test results in various ways
• Screens for Down syndrome, trisomy 13, trisomy 18, and NTDs

Cell-free DNA screening

• Timing: 10 weeks and beyond
• Blood test
• Screens for Down syndrome, trisomies 13 and 18, and sex chromosome abnormalities

Second-trimester Screening (“quad screen”)

• Timing: 15–22 weeks
• Blood test
• Screens for Down syndrome, trisomy 18, and NTDs

Standard Ultrasound Exam

• Timing: 18–22 weeks
• Screens for some physical defects

Diagnostic Tests

These tests can tell you whether your baby actually has certain genetic disorders.

[Tests are displayed on a graph according to their recommended timing during pregnancy.]

CVS

• Timing: 10–13 weeks
• Tests fetal cells in a sample of chorionic villi
• Detects Down syndrome, trisomy 13, trisomy 18, and inherited disorders for which you request testing but not NTDs

Amniocentesis

• Timing: 15 weeks and greater
• Tests fetal cells in a sample of amniotic fluid
• Detects Down syndrome, trisomy 13, trisomy 18, inherited disorders for which you request testing, and certain types of NTDs

Abbreviations: CVS, chorionic villus sampling; NT, nuchal translucency; NTD, neural tube defect.

Note: Check your local and state laws regarding the timing and availability of prenatal genetic testing.

PFSI010: This information was designed as an educational aid to patients and sets forth current information and opinions related to women’s health. It is not intended as a statement of the standard of care, nor does it comprise all proper treatments or methods of care. It is not a substitute for a treating clinician’s independent professional judgment. Please check for updates at www.acog.org to ensure accuracy.

Copyright December 2019 by the American College of Obstetricians and Gynecologists. No part of this publication may be reproduced, stored in a retrieval system, posted on the internet, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without prior written permission from the publisher.