No. Ultrasound a high-frequency sound waves, no radioactivity, safe and harmless to the human body, applied to the whole body organs and systems as well as used for obstetrics, pregnant women and fetuses are also very safe.
During the examination, the doctor will apply a layer of sticky stuff for the patient, a liquid called coupling agent, which aims to make better contact between the probe and the skin, facilitating the conduction of sound waves and improving the quality of imaging. The coupling agent is non-toxic and harmless to the human body, so just wipe it off or wash it with warm water after the examination and don't worry about it.
"Color ultrasound" and "B ultrasound" are different
Zhang Haichun pointed out that "color ultrasound" is not colorful, and most hospitals are currently using the Color Doppler ultrasound diagnostic equipment, which can show the blood flow, depending on the direction of blood flow is displayed in red or blue, while the organs, tissues or foci are still in gray, black or white form on the screen.
If there is a need to view the blood flow, the doctor will turn on the color ultrasound function. In addition, because the color ultrasound image is clearer than the black and white "B ultrasound", so it is best to do color ultrasound if possible
Refer to: People's Daily Online - Ultrasound: Is it harmful to the human body?