The safety of prenatal ultrasound exposure in human studies.

Diagnostic ultrasound use in obstetrics has been growing rapidly to become an integral part of prenatal care today. The high proportion of exposure to prenatal ultrasound highlights the public health significance of routine ultrasound use. A majority of epidemiologic studies tends to support the safety of diagnostic ultrasound use during pregnancy. However, there have been some reports that there may be a relation between prenatal ultrasound exposure and adverse outcome. Some of the reported effects include growth restriction, delayed speech, dyslexia, and non-right-handedness associated with ultrasound exposure. Continued research is needed to evaluate the potential adverse effects of ultrasound exposure during pregnancy. These studies should measure the acoustic output, exposure time, number of exposures per subject, and the timing during the pregnancy when exposure(s) occurred, while controlling for potential confounding variables such as sociodemographic, medical, and obstetric risk factors. We recommend that a new consensus development conference be held to gather the needed data and provide guidelines for the future research needs, as well as respond to the rapid advances in this technology.