An ultrasound scan sends high frequency sound waves through the tummy into the uterus.These bounce off the baby and a computer translates the returning echoes into an image.The image shows the baby's position and movements.
Fluids (such as the amniotic fluid that the baby lies in) do not reflect any echoes, so appear black.
It is the contrast between these different shades of white, grey and black that allows your doctor to interpret the images.
Most parents look forward to their scan because it gives them the first glimpse of their baby.
In India, it is illegal and a punishable offence to reveal the gender of your baby with the help of ultrasound during pregnancy.
So you will not find out if you are expecting a son or daughter.
Still, seeing the first images of your baby can be a strong bonding moment.The ultrasound report will have a printout of your baby's images.However, it is important to remember that the main purpose of the scan is not to provide the first photo for your baby album.It is to check that your baby is growing and developing normally.3D and 4D colour scans are becoming very popular because they offer a more life-like image of your baby.Ultrasound scans have been used in pregnancy for more than 40 years with no known side-effects.