Fig. 2From: Towards more accurate measurement of edge to os distance in low-lying placenta using three dimensional transvaginal ultrasound: an innovative techniquePlane A (sagittal view of the cervix) after manipulations (The IO was centered in the plane, the reference point was positioned at the IO then rotation around the z-axis to make the IO (arrow) at the lowest level in the lower uterine segment)Back to article page