Study observation:Find:Pt:Nuchal fold^Fetus:Nar:US
study observation:find:pt:nuchal fold^fetus:nar:us
Study observation:Finding:To identify measures at a point in time:Nuchal fold^Fetus:Narrative:Ultrasound
study observation:finding:to identify measures at a point in time:nuchal fold^fetus:narrative:ultrasound