Pregnancy outcomes in unselected singleton pregnant women with an increased risk of first-trimester Down's syndrome.

Background: The purpose of this study was to assess outcomes in pregnancies with a positive screen of first-trimester combined test (nuchal translucency, pregnancy-associated plasma protein-A and free beta-human chorionic gonadotropin).

Methods: Using a cut-off level of 1 in 270, 216 (7.1%) women had a positive screen.