The present invention relates to an ultrasound elastography system and method for providing a strain image of an anatomical site. The system comprises a signal processing unit (103) configured to receive a time-varying ultrasound signal from an ultrasound probe (101) having at least one transducer element, to determine axial motion data based on the time-varying ultrasound signal, the axial motion data indicating a relative axial motion between the ultrasound probe and the anatomical site in an axial direction (y), and to determine a lateral variation of the axial motion in a lateral direction (x) based on the axial motion data. The system further comprises a display unit (105) configured to display a strain image (200) of the anatomical site based on strain image data which is determined based on the axial motion data, and to display an indication of lateral variation of a quality of the strain image based on the lateral variation of the axial motion.
