What Exactly is an Ultrasound

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What Exactly is an Ultrasound

All types of ultrasound are a medical procedure which is otherwise known as a scan. This involves high frequency sound waves transmitted through the body and then picked up on a screen.

During pregnancy, a device known as a transducer is used to move along the mother’s abdomen and this sends sound waves via her abdomen and through her uterus. These sound waves bounce off the baby in the form of echoes. A computer picks up the echo messages and translates them onto a screen. As the baby moves and kicks, images can be seen on the ultrasound screen. These sound waves are very high in pitch and intensity and cannot be heard by the human ear.

Ultrasound is a painless and non invasive procedure. However, as you may need to have a full bladder if you are in the early stages of your pregnancy, it can be a little uncomfortable.

What’s the difference between a 3D and 4D ultrasound?

4D or 4 dimensional scans build on the technology of 3D scans. The extra dimension is time, so that effectively 4D ultrasounds are moving images of your baby in real time. As your baby kicks, moves, frowns, grimaces, sucks their thumb, opens their eyes and moves their lips, you will be able to see these movements on the scan as they are actually happening.

The technology associated with 4D ultrasounds makes them more expensive and they are not generally offered as part of a routine obstetric service.

3D Ultrasounds are also known as elective prenatal ultrasounds. They are not designed to replace the standard 2D procedure which is commonplace obstetric procedure. Instead they offer a more enhanced “bonding” experience with the unborn baby and are instigated by parents choosing to have them done, rather than a medical need. 
Some parents are very keen to see for themselves how their baby is growing and developing, and for this reason another name for the 4D ultrasound is a “lifestyle” scan.

Important information

Both 3D and 4D ultrasounds are not designed to replace a standard obstetric ultrasound. Many companies will not do a 3D or 4D ultrasound unless a 2D medical diagnostic ultrasound has been done first. This is to screen out any abnormalities for both the mother and her baby.

Mothers also need to be engaged with a pregnancy healthcare provider first before having a 3D or 4D ultrasound.


When should I have my 4D ultrasound?

There is some discrepancy between clinics around when a 3D and/or 4D ultrasound should be done. Many claim the optimum time is somewhere between 27-32 weeks of gestation and others state between 26- 30 weeks. On either side of these time frames a three week “window” will still provide a good viewing alternative.

From 19-24 weeks of gestation, gender determination scans can be done. At this early stage though, the baby does not have enough fat to “fill out” its facial features, so the quality of the scan and images you’ll see won’t be as clear as they will be later. Waiting for just a little longer and being patient will reap a lot of benefits!