The ‘BIG’ scan or anomaly scan (20 week scan) really is a mum-to-be milestone, and as pregnancy events go it is up there as one of the big ones.

You may want to share this special occasion with someone so you can be reassured that you will be allowed bring someone with you.  Most hospitals only allow one person to attend with you.

So what happens during the scan?

This scan is pretty much the same as your 12 week scan or dating scan. However it may take a bit longer – between 30 minutes and an hour. This is because it’s looking at more specific aspects of your baby’s development. A full bladder is recommended.

pregnancy scan

While the excitement can often revolve around finding out the sex of the baby there are some other very important things the sonographer will be looking out for:

Firstly… From 20 weeks, the sonographer can clearly see individual structures in your baby, structures such as the heart and brain.  So the sonographer will look in detail at your baby’s organs and how things like their  hands, tummy, face, spine and feet are forming, as well as the circumference of his head. All of these measurements can help detect certain conditions including cleft lip.

Secondly… The location of your placenta will also be checked. This is to rule out or confirm if it’s low lying which may affect your mode of delivery.

Thirdly…  The amount of amniotic fluid will also be measured.

And the big one…. Should you choose to find out….The sex of the baby.

Finding out the sex is not always 100% guaranteed!!! It depends on what way your baby is lying at that particular time so don’t be disappointed if the sonographer is unable to tell you…They want to be 100% sure too.

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Bump size & baby size