Ultrasound procedure :
The procedure depends on the type of ultrasound used, but may include:

• Transabdominal ultrasound : sound waves pass very well through water. The sonographer uses your full bladder as a ‘porthole’ to your uterus, so you will have to drink plenty of water before the test. You lie down on an examination table or bed. Gel is applied to your abdomen (to provide better contact between your skin and the scanner) and the sonographer moves the scanner in various positions. Pictures are sent instantly to a nearby monitor. The sonographer may have to push quite firmly at times in order to see the deeper structures. The scan usually takes about 30 minutes.
• Vaginal ultrasound : in some cases, a transabdominal ultrasound can’t produce clear enough pictures. There may be too much air in your bowel, for instance, and air is a poor conductor of sound waves. In these cases, a slender scanner is inserted into your vagina. The scan usually takes about 30 minutes.