An ultrasound system (100) and operating method (200) are disclosed in which the system is adapted to receive a sequence (15) of 2-D ultrasound image frames (150) of a prenatal entity from an ultrasound probe (14) and, for each image frame in said sequence, control the display device to display the received image frame； attempt to segment the image frame for recognition of an anatomical feature of interest (151) of said prenatal entity in said image frame； and accept the image frame for further processing upon recognition of said feature, said further processing comprising: determine a geometric property of the recognized anatomical feature of interest for each accepted image frame； and control the display device to display the determined geometric properties of the accepted image frames in said sequence with each displayed image frame. Such an operating method may be made available as a computer program product for installation on the ultrasound system.
