What the 20-week scan is for

The 20-week scan can happen anywhere between 18 and 20 weeks. It shows what’s going on for your baby about halfway through the pregnancy.

This detailed ultrasound:

• looks at your baby’s body parts, including internal organs
• checks the location of the placenta
• picks up any obvious problems in your baby’s development or growth, like spina bifida, heart defects and limb defects.

If you want to find out the sex of your baby, this is the time to ask. Say what you want before the scan, so the sonographer can have a close look and tell you (or keep it secret). Keep in mind that sex identification in this scan is about 95% accurate.

This scan is sometimes called a morphology scan.

What you can see at the 20-week scan

At the 20-week scan, you’ll probably see your baby’s heart beating, the curve of baby’s spine, baby’s face, and baby’s arms waving and legs kicking. There might even be some cute thumb-sucking.

Because you can see so much in this scan, you might get a stronger sense of the baby or babies coming into your life.

Usually you can get an ultrasound photo or even a DVD to share with family and friends. Some services have 3D or even 4D ultrasound scanners, but these scans often cost extra.

Miscarriage or health problems at 20 weeks

It’s rare to lose a pregnancy after about 13 weeks. The overall risk of miscarriage after this time is only about 3%.

There’s a small chance that the scan might pick up a serious health problem or complication. Some abnormalities won’t be seen on a scan at all or can’t be seen until later in the pregnancy.

Genetic conditions like Down syndrome can be diagnosed only by special antenatal tests like amniocentesis. If you’re thinking about having these tests, genetic counselling services can give you more information about them.

Things you can do

• Decide with your partner on whether you want to find out your baby’s sex.
• Make the 20-week scan appointment with your partner for a time and day that suits you too, if possible.
• Well ahead of the day, ask your employer for time off work so you can go to the scan. Going to the ultrasound is one of the few chances you’ll get to see your baby before birth.
• Read more about tests during pregnancy.