The Real Sound of Ultrasound

Ultrasound diagnostics allow us to receive images from inside the body by directing waves of high-frequency sound at the uterus and fetus inside.

Though technicians and the women who are being observed cannot hear the frequencies of the ultrasound, the immediate proximity of the fetus's delicate hearing to the soundwaves results in the baby actually hearing the ultrasound waves as loud as 100-120dB. That's the equivalent of standing next to a jackhammer or a freight train!

The article "Quiet, Please! Says the Fetus" is from the Acoustical Association of America and explains why ultrasound is so loud for babies inside the womb, and urges more research and caution when stimulating the unborn through excessive ultrasound exposure.