1. A method of obtaining symmetry information of objects, the method comprising: obtaining an ultrasound image of the objects, the ultrasound image containing at least one first feature point; acquiring at least one second feature point in a mirror image obtained by reversing the ultrasound image based on an arbitrary axis, the at least one second feature point in the mirror image matching the at least one first feature point in the ultrasound image under a predetermined algorithm; acquiring a third feature point in the ultrasound image, the third feature point corresponding to a location of the second feature point in the mirror image; determining a symmetry axis of the objects by using a center point between the first feature point and the third feature point; and acquiring symmetry information indicating whether the objects are symmetrical about the determined symmetry axis.