Menu Healthy Lifestyle Diseases & Conditions First Aid Symptoms Tests & Procedures Videos Definitions FAQs Edwards syndromeUpdated: 2017-06-13OverviewEdwards syndrome is a genetic condition in which an extra copy of chromosome 18 causes severe developmental delays. It's usually fatal by age 1.A first trimester screening including a blood test and ultrasound offers early information about a baby's risk of having it. A second trimester blood test called a quad screen can also detect it. © 1998-2022 Mayo Foundation for Medical Education and Research(MFMER). All rights reserved. Terms of Use