It is a modern stethoscope of present doctor most commonly and most widely used without any hazard of radiation and thus most useful and popular in obstetrics Sonography that is for pregnant mothers and their unborn baby.

At present colored ultrasound machine are in routine use which facilitates to watch blood flow by color Doppler technique which is based on a very well known scientific effect called Doppler’s effect. Doppler is used in all body parts except lungs and bones.