NEW YORK (Reuters Health) - A screening program that combines standard testing in the first trimester with multiple-marker testing in the second trimester can detect 98% of trisomy 21-affected pregnancies, new research shows. However, with this strategy, up to 17% of patients will be considered at risk and undergo an invasive test.
The findings, which appear in the October issue of Obstetrics and Gynecology, are based on a study of 4325 pregnant women who underwent standard first trimester screening for trisomy 21 and then multiple-marker screening in the second trimester. The markers included alpha-fetoprotein, unconjugated estriol, and total HCG.
The women included 4145 with a negative first trimester screen and 180 with a positive screen, lead author Dr. Lawrence D. Platt, from Cedars-Sinai Medical Center in Los Angeles, and colleagues note.
All women with a positive screen as well as those who were 35 years of age or older were offered an invasive procedure during the second trimester to determine trisomy 21 status, the investigators point out.
Seven trisomy cases were observed in both the first trimester screen-negative and screen-positive groups. In the screen-negative group, 6 of the 7 cases were detected with multiple-marker screening in the second trimester with a false positive rate of 8.9%. In the screen-positive group, all 7 cases were detected, but the false positive rate was 38.7%.
“These results continue to demonstrate a superior screening efficiency in the use of multiple markers for the detection of trisomy 21 and further support for the need to abandon the use of maternal age alone as a basis for invasive testing,” the researchers conclude.
Source: Obstet Gynecol 2004;104. [ Google search on this article ]
MeSH Headings:Diagnosis: Diagnostic Techniques, Obstetrical and Gynecological: Prenatal Diagnosis: Diagnostic Techniques and Procedures: Analytical, Diagnostic and Therapeutic Techniques and EquipmentCopyright © 2002 Reuters Limited. All rights reserved. Republication or redistribution of Reuters content, including by framing or similar means, is expressly prohibited without the prior written consent of Reuters. Reuters shall not be liable for any errors or delays in the content, or for any actions taken in reliance thereon. Reuters and the Reuters sphere logo are registered trademarks and trademarks of the Reuters group of companies around the world.
