•Routine Diagnostic Tests During The Antepartum Period:      A.IMAGING ULTRASOUND AND DOPPLER TECHNIQUES Ultrasound pulses, which are sent into the body and produce echoes as they bounce off organ boundaries and within tissues, are ultra-high-frequency sound waves, which extend far beyond the normal range of acoustic vibration, falling between 2 and 10 megahertz, or 2 to 10 million cycles per second. These echoes are picked up by a transducer, and further converted as scan lines on a display monitor to form a picture of the underlying tissue from the emerging pattern of these waves. Doppler techniques, that are employed [...]