Baker M L, Dalrymple G V
Radiology. 1978 Feb;126(2):479-83. doi: 10.1148/126.2.479.
Biological effects from experimental ultrasound studies, such as chromosome aberrations and retardation of growth, have been recorded but mostly at levels far in excess of diagnostic intensity. The data surveyed in this review suggest that there is apparently little or no danger associated with diagnostic ultrasound exposure at clinical levels.