20 Week Ultrasound - Baby's Development

At the 18-20 week scan, your baby's development is checked. It's also a wonderful chance to see your baby up close.

Your big scan

The 18-20 week scan is a real milestone in your pregnancy – giving you the chance to see your beautiful baby growing inside you.

Generally recommended around 18-20 weeks, this ultrasound – called the fetal morphology or anomoly scan – is a thorough head-to-toe check of your baby and its surrounds. It takes between 30 and 60 minutes.

One thing you’ll need to decide before you go into the scan is whether you want to find out if the baby is a boy or a girl. Some mums and dads want to know; others prefer to keep it a surprise for the birth. Remember, though, it’s not always possible to find out the sex – it can depend on your baby’s position during the scan.

Why 18-20 weeks for your ultrasound?

From about 18 to 20 weeks, your baby’s organs are becoming much more fully developed. It’s possible for the sonographer to detect some anomalies using ultrasound – so that, if needed, the right care is available from the moment your baby is born.

They will also look at your baby’s surrounding environment to make sure that everything is going well.

By taking some measurements, they can also confirm your baby’s due date.

What does the sonographer look at?

During the ultrasound, the sonographer will look at:

  • Your baby’s head, to check for any brain problems or cleft lip/palate
  • Your baby’s spine and abdomen to see that everything is aligned and developed
  • The size and shape of your baby’s heart
  • The stomach, which you should be able to see below the heart. You might be able to see some of the amniotic fluid your baby has swallowed – it will look like a black bubble in its tummy!
  • Your baby’s kidneys and bladder
  • Your baby’s hands and feet – although they probably won’t count the fingers or toes
  • The placenta, umbilical cord and amniotic fluid
  • The measurements of your baby’s head, abdomen and thigh bone to ensure that they are growing equally well

Sometimes, if your baby is not lying in the right position or you are carrying a little excess weight, the sonogrpaher may not be able to see everything they need to. In this case, they may book you in for another scane in a few weeks. 

If there are any signs of problems, you should be told straight away and referred on to the appropriate health professional.


Want to know more? Call us on 1800 842 098 or Live Chat now.


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