Understanding 2D, 3D and 4D pregnancy ultrasounds

If you're expecting a baby, you can most certainly expect a baby ultrasound scan. In the UK the NHS offers at least two ultrasound scans during pregnancy one at around 12 weeks and one at 20 weeks. You can also opt for a private pregnancy scan if you need further reassurance through your pregnancy.
 

The Ultrasound Scan

The word “ultrasound” might sound complicated, but it's not. An ultrasound scan is a diagnostic technique which has many purposes but it is better known to be used during pregnancy to monitor the foetus in the mother's womb.
During your scan an ultrasound probe or wand is moved around your skin sending high frequency ultrasounds inside your body and the computer analyses the returning echoes and plots the image on the screen. You can read more about what is an ultrasound.
 

Are pregnancy Ultrasound safe?

 
As ultrasound imaging involves bouncing the sound waves off of internal objects to produce an image, it is considered safe for mother-to-be and the baby and can help to ensure the baby is healthy making it pregnancy ultrasound a true must-have.

 

What is a 2D Ultrasound?

A general baby ultrasound produces a 2D (a two-dimensional still view) image of the foetus. This image  generally appears on the ultrasound screen in different shades of black and white.

Ultrasound imaging started as 2D imaging and as technology improved and computers became faster the ultrasound machine progress to 3D and 4D technology. You an read more about the history of ultrasound on the linked article.

What is a 3D Ultrasound?

 A 3D scan is a 3 dimensional image of the baby anatomy and they let you see the baby's face for the first time. 3D scans can be performed with a standard 2D probe or with a special 3D probe.

If a standard 2D probe is used the sonographer will move the probe in a steady speed to obtain the image but with a 3D probe the sonographer only needs to rest the probe on the correct location and the probe moves internally to obtain the desired image.

What is a 4D Ultrasound?

A 4D ultrasound is nothing more than a 3D scan with the added dimension of time and therefore you can see your baby in real time.

Are 4D ultrasound safe?

 4D ultrasound are considered safe in experienced hands as they are still use sound.  Some doctors might use 3D and 4D ultrasounds because they can show certain birth defects, such as cleft palate, analysis of amniotic fluid, placenta and foetal-placental circulation better than 2D scans.

When these scans are offered as bonding scans with no medical benefit most of the healthcare bodies are against the practice due to unnecessary exposure of the foetus as  too much exposure to any ultrasound may not be good for your baby. So getting an ultrasound just to see your baby's face may not be a good idea -- especially at an ultrasound centre that may not employ highly skilled NHS sonographers.

At International Ultrasound Services in London we offer a wide range of baby scans complementary to the NHS but we do not offer 4D ultrasounds.

Written by:

Updated on:

  • September 30, 2024

Medically Reviewed by Tareq Ismail Pg(Dip), BSc (Hons)