Contributor: Eric Dellinger, MD
Last Update: 6/24/2011
“Diagnostic ultrasound studies of the fetus are generally considered safe during pregnancy. This diagnostic procedure should be performed only when there is a valid medical indication, and the lowest possible ultrasonic exposure settings should be used to gain the necessary diagnostic information under the as low as reasonably achievable (ALARA)principle.
The promotion, selling, or leasing of ultrasound equipment for making “keepsake fetal videos” is considered by the US Food and Drug Administration to be an unapproved use of a medical device. Use of a diagnostic ultrasound system for these purposes, without a physician’s order, may be in violation of state laws or regulations.
Diagnostic ultrasound has been in use since the late 1950s. Given its known benefits and recognized efficacy for medical diagnosis, including use during human pregnancy, the American Institute of Ultrasound in Medicine herein addresses the clinical safety of such use:
No independently confirmed adverse effects caused by exposure from present diagnostic ultrasound instruments have been reported in human patients in the absence of contrast agents. Biological effects (such as localized pulmonary bleeding) have been reported in mammalian systems at diagnostically relevant exposures but the clinical significance of such effects is not yet known. Ultrasound should be used by qualified health professionals to provide medical benefit to the patient.”
Given recent concerns about possible associations between ultrasound energy exposure to the fetus and neonatal developmental problems such as autism, the AIUM and others have advocated for continued use of sonography in a safe and medically justifiable manner. These OBTS guidelines are intended to emphasize that approach.
1) Since energy delivery is a product of both time and power, both of these parameters should be kept to acceptably low levels to allow completion of an informative diagnostic study.
2) Studies performed for entertainment purposes should not be allowed.
3) Studies should have a valid medical indication.
4) Power output levels should be routinely monitored and kept within accepted safety ranges.
5) Equipment should be maintained in proper working order and professionally serviced.
1) Perform the minimal study necessary to obtain the essential information requested.
2) For documentation of cardiac activity, use M-mode scanning in preference to color or pulsed Doppler where possible.
3) If the fetal NT measurement and scan are normal, use of color and pulsed wave Doppler are not indicated.
4) Umbilical artery Doppler measurements may be made in the 2nd and 3rd trimesters routinely as a screen for placental pathology.
5) If umbilical artery Dopplers and fetal growth are normal, MCA and venous Dopplers are not indicated.
6) When performing MCA Dopplers, take care to avoid applying Doppler energy to the fetal cranium. Minimize the exposure duration and try to keep the Doppler window away from fetal bone.
7) If MCA Dopplers are normal, fetal venous Dopplers are probably not indicated.
8) Minimize the use of 3D/4D imaging. 3D sectional plane imaging may be preferred given its shorter duration of exposure.
9) If 4D imaging is performed for patient satisfaction, minimize the time of use. Recording the 4D study onto portable media will allow prolonged viewing at the patient’s leisure.