Ultrasound imaging, also called ultrasound scanning, is a method of obtaining pictures from inside the human body through the use of high frequency sound waves.
Obstetric ultrasound refers to the specialised use of this technique to observe your unborn baby while it is inside your uterus (womb). The sound waves are emitted from a hand-held nozzle, which is placed on your stomach, and reflection of these sound waves is displayed as an image of the moving foetus (unborn baby) on a monitor screen. No x-rays are involved in ultrasound imaging.
Assessment of the foetus can help to detect major abnormalities in the baby, however not all abnormalities can be detected in this way. Ultrasound measurements can also help determine the size and growth of the baby and help to confirm the estimated due date.