Study observation.general 1st trimester:Imp:Pt:^Fetuses:Nar:US
study observation.general 1st trimester:imp:pt:^fetuses:nar:us
Study observation.general 1st trimester:Impression/interpretation of study:To identify measures at a point in time:^Fetuses:Narrative:Ultrasound
study observation.general 1st trimester:impression/interpretation of study:to identify measures at a point in time:^fetuses:narrative:ultrasound