Ultrasound scans in pregnancy

Routine pregnancy ultrasound scans
These are offered in:

• the first trimester at around 11-13 weeks
• the second trimester at around 18-20 weeks.

Non-routine pregnancy ultrasound scans
In early pregnancy, your midwife or doctor might recommend a non-routine pregnancy ultrasound scan if:

• You have vaginal bleeding or abdominal pain.
• There’s uncertainty about your pregnancy dates.

Later in pregnancy, your midwife or doctor might recommend extra ultrasounds if:

• There are concerns about your health or your baby’s health and development.
• There were complications in a previous pregnancy.
• You’re expecting twins or multiples.
• Your baby is overdue.

Pregnancy ultrasound scans are safe for you and your baby. It’s your choice whether to have these scans.

The 20-week scan: what it’s for

The 20-week ultrasound scan is one of the recommended routine tests in pregnancy. It:

• checks that your baby is developing as expected
• checks the position of the placenta
• checks the length of your cervix
• looks at your baby’s body parts and organs
• looks at the umbilical cord, blood flow and amniotic fluid surrounding your baby
• can usually pick up on conditions like spina bifida, congenital heart disease and limb differences
• can indicate whether to do more tests for certain genetic conditions.

If you’re interested in finding out your baby’s sex, you can ask the ultrasonographer to look. But the ultrasonographer won’t always be able to tell the sex for sure.

This 20-week ultrasound scan usually happens at an ultrasound clinic or a public hospital department. The results will be sent directly to your midwife or doctor. They’ll contact you to let you know about the results or discuss them with you at your next appointment.

This scan often happens at around 20 weeks in pregnancy, but it can happen anywhere between 18 and 20 weeks. It’s 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 their spine, their face, and their 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.

If you want a photo or video of your baby, ask the clinic or hospital what it offers. Some services will give you a hard copy, and others might send them to you digitally. Some services have 3D, 4D or even 5D ultrasound scanners, but these scans often cost extra.

Miscarriage, development problems or health conditions at 20 weeks

Most 20-week scans show that babies are developing well.

It might help you to know that the 20-week scan is unlikely to show that there has been a miscarriage. From about 13 weeks, miscarriages are uncommon.

Sometimes the 20-week scan picks up development problems, health conditions or other complications. For example, around half of all babies with congenital heart disease are diagnosed through pregnancy ultrasound scans.

Some development problems and health conditions in unborn babies won’t need much, if any, treatment. But others might be more serious. It’s worth thinking about how you might feel if the ultrasound picks up on serious problems or conditions. You and your partner will need support. Your midwife or doctor will be able to help.

What is an ultrasound scan?

An ultrasound scan is a medical technique used to look inside your body and make images using high-frequency sound waves. Ultrasound scans are often used to look at the soft tissues beneath the skin, like the muscles, organs and tendons. They can also be used to look at unborn babies and placentas.

If you’re having a pregnancy ultrasound scan, an ultrasonographer will put gel onto your abdomen and then move a probe across your skin. You’ll see images of your baby on a screen next to the ultrasonographer.