Clinical end users worldwide show poor knowledge regarding safety issues of ultrasound during pregnancy.

E-mail: [email protected] he use of diagnostic ultrasound (DUS) has become widespread, in labor rooms, private offices, emergency departments, and even the shopping mall,1,2 and is widely perceived as safe.2,3 Indeed, there has been no independently longestablished report that DUS is harmful. However, as a form of energy, DUS has the potential to have effects on living tissues, that is, bioeffects.1,2,4 The two most likely mechanisms for bioeffects are heating and cavitation.1–3 The following section of this issue is dedicated to reporting results of the American Institute of Ultrasound in Medicine–sponsored Keystone conference, which dealt directly with these bioeffects. Many scientists took part in the conference to generate state-of-the-art information on the subject. It is imperative to try and assess clinical end users’ familiarity with these issues. Recently, two studies evaluated ultrasound end users’ knowledge of safety issues.5,6 Marsal5 distributed a questionnaire to professionals using ultrasound for fetal examinations in Europe. The questionnaires were answered by participants and faculty members of staff meetings and postgraduate courses in obstetric ultrasound, Doppler ultrasound, and fetal echocardiography in Sweden, Norway, and Austria. One hundred ninety-