FTP, identify this method of examining the shape and movement of organs in the body, most associated with pregnancies.
The frequencies of the waves used range from 1 to 10 MHz, and the signal is produced by the application of a steady electrical sine wave applied to a transducer.  The distance from the reflecting surface is obtained from the time delay of the echo and the Doppler shift of frequency is used to measure speed of moving objects such as red blood cells, and a coupling gel is usually used to eliminate the air gap between the transducer and the patient's skin.  FTP, identify this method of examining the shape and movement of organs in the body, most associated with pregnancies.
The frequencies of the waves used range from 1 to 10 MHz, and the signal is produced by the application of a steady electrical sine wave applied to a transducer.  
Ultrasound