The invention provides an adjustable means for supporting the breast from beneath the nipple during a prone breast biopsy procedure. By increasing or decreasing the volume of air or fluid within the pillow, the clinician can apply a controlled amount of compression on the breast, thereby increasing or decreasing the compressed area of the breast. The invention is believed to have utility for all modalities of breast biopsy; however, it is believed to be especially useful for a prone MRI breast biopsy procedure.