Pregnancy scan, 2nd and 3rd trimester

anomaly scan · 20 week scan · growth scan · third trimester scan · Doppler scan in pregnancy

An ultrasound of your baby in the second and third part of pregnancy. The doctor checks how the baby is growing, the baby's organs, the placenta, and the fluid.

Offered to all pregnant women: the second scan usually at 18 to 21 weeks, the third at about 30 to 34 weeks. Your doctor will tell you the exact timing.

⏱ Duration: usually 30 to 40 minutes

Be sure to tell your doctor

How many weeks pregnant you are, and your first scan results
If you are expecting twins or the pregnancy is after IVF
If you have had discharge, pain, or changes in the baby's movements
Long-term health conditions and medicines

How to prepare

Preparation. No special prep needed. A full bladder is usually not needed at this stage.
Food. You can eat as usual. Do not come hungry.
Clothes. Wear something comfortable so your belly is easy to uncover.

What to bring

Your pregnancy record or referral
Results of past scans and ultrasounds
A tissue or towel

How it goes

You lie on your back with your belly bare
The doctor puts on gel and looks at the baby through your belly
The baby's growth is measured and the organs are checked
The placenta, the amount of fluid, and the cervix are checked
At the third scan, blood flow is often checked. This is called Doppler

What you'll feel

It does not hurt. You feel the probe pressing
If you feel dizzy or sick lying on your back, say so. You will be turned onto your side
You may see your baby on the screen

Afterwards

You usually get the report right away
If something needs a closer look, the doctor will tell you which tests you need

Contact a doctor straight away if

Bleeding, leaking fluid, or severe belly pain: call emergency services
The baby is moving much less than usual: see a doctor right away
A severe headache, spots before your eyes, or a swollen face: call emergency services

Common questions

Can I find out the baby's sex at the second scan?

Usually yes, if the baby is lying in a good position. But the main goal is to check how the baby is developing.

Why have a third scan if the second one was fine?

Near the end of pregnancy, it matters how the baby is growing, how the placenta is working, and how the baby is lying before birth.