An ultrasound scan sends sound waves through your womb (uterus). The echoes are then turned into an image on a screen that shows your baby’s position and movements.Hard tissues, such as bone, reflect the most sound waves and so make the biggest echoes.Your first scan can be very exciting because it gives you a first glimpse of your baby.
Most of the time, the placenta has moved into a better position by the time you're 32 weeks pregnant.
A full bladder helps the ultrasound echoes to reach your womb, giving the sonographer a good view of your baby.
If your baby's still deep in your pelvis, or if you're overweight, the image won't be very clear.
Sonographers are radiographers or midwives who are trained in ultrasound. SCo R/BMUS guidelines for professional ultrasound practice. Society and College of Radiographers and British Medical Ultrasound Society.
They usually have a postgraduate certificate, diploma, or master's degree in medical ultrasound, and will carry out most of your scans.
This is because the sound waves go through them with no echoes.