It's very exciting to "see" your baby in the womb, often moving his or her hands and legs.
Most scans are carried out by specially trained staff called sonographers.
The procedure is carried out in a dimly lit room so the sonographer is able to get good images of your baby. You will then be asked to lower your skirt or trousers to your hips and raise your top to your chest.
The sonographer will put ultrasound gel on your tummy and tuck tissue paper around your clothing to protect it from the gel.
The gel makes sure there is good contact between the machine and your skin.
The sonographer passes a handheld device called a probe over your skin.
It is this probe that sends out ultrasound waves and picks them up when they bounce back.A black and white picture of the baby will appear on the ultrasound screen.Ultrasound scans use sound waves to build a picture of the baby in the womb.The scans are completely painless, have no known side effects on mothers or babies, and can be carried out at any stage of pregnancy.Talk to your midwife, GP or obstetrician about any concerns you have.For many women, ultrasound scans are the highlight of pregnancy.