Ultrasound is a common medical imaging technique used during pregnancy to monitor fetal health and development. This non-invasive procedure utilizes sound waves to create real-time images of internal structures. Many expectant parents wonder about the safety of these examinations, particularly concerning their frequency. Understanding the technology can help address these worries.
How Ultrasound Technology Works
Ultrasound technology relies on high-frequency sound waves to generate images of the body’s interior. A device called a transducer, or probe, sends these sound waves into the body and then captures the echoes that bounce back from tissues and organs. The transducer converts electrical currents into sound waves, which travel through the body at varying speeds depending on the density of the tissues they encounter.
As these sound waves reflect off different structures, such as the baby’s body or amniotic fluid, the transducer receives the echoes. A computer then processes these echoes to construct a real-time image displayed on a screen. This imaging method does not use ionizing radiation, unlike X-rays or CT scans.
Assessing Ultrasound Safety
The primary biophysical effects of ultrasound on tissues are thermal effects and mechanical effects, which include cavitation. Thermal effects refer to a slight increase in tissue temperature as sound energy is absorbed and converted into heat. Modern diagnostic ultrasound machines are designed to operate at levels that produce minimal temperature increases, well below thresholds that would cause harm when used appropriately.
Cavitation involves the formation of microscopic gas bubbles within body fluids or tissues due to the pressure changes from the sound waves. While these bubbles can potentially grow or collapse, diagnostic ultrasound systems typically operate at output levels that minimize the likelihood of harmful cavitation. Extensive research supports the safety of diagnostic ultrasound when performed by trained professionals. No confirmed evidence suggests harm to the fetus from medically indicated diagnostic ultrasound examinations.
Professional Recommendations for Ultrasound Use
Medical organizations like the American Institute of Ultrasound in Medicine (AIUM) and the U.S. Food and Drug Administration (FDA) provide guidelines for ultrasound use during pregnancy. These bodies advocate for the principle of “As Low As Reasonably Achievable” (ALARA), meaning exposure should be minimal for diagnostic information. This approach ensures that the benefits of the scan outweigh any theoretical risks.
Medical professionals should only perform ultrasounds when there is a clear medical indication, such as checking fetal growth, assessing gestational age, or identifying potential complications. All fetal ultrasound examinations should be performed by qualified and credentialed personnel with specialized training. These guidelines emphasize regulated and purposeful use, reinforcing the safety of ultrasound within medical settings.
The Role of Non-Medical Ultrasounds
The distinction between medically indicated diagnostic ultrasounds and non-medical, or “keepsake,” ultrasounds exists. Diagnostic ultrasounds are ordered by a healthcare provider for medical purposes to monitor fetal health or diagnose conditions. In contrast, non-medical ultrasounds are performed primarily for entertainment, such as obtaining 3D or 4D images or videos.
Concerns arise with non-medical ultrasounds due to several factors, including the lack of medical necessity and potential for prolonged exposure times. Operators in keepsake ultrasound businesses may not always be medically trained to recognize or interpret findings, or they might use equipment outside of recommended diagnostic protocols. The FDA and AIUM discourage the use of ultrasound for non-medical purposes because the long-term effects of repeated or lengthy exposures are not fully known. Medical supervision and appropriate training are important for all ultrasound procedures to ensure safety.