The 20-week scan — sometimes called the anomaly or mid-pregnancy scan — usually takes place between 18 and 21 weeks. It's a detailed examination of your baby's physical development.
It looks for a number of physical conditions, most of which are rare. For most parents, it's reassuring; occasionally it finds something that needs a closer look or follow-up care.
🔍What it checks
- Detailed measurements of the head, abdomen and thigh bone
- The brain and spine
- The heart and major organs
- The face, lips and abdominal wall
- The position of the placenta
💛What to expect
The scan is done over your tummy and usually takes around 20–30 minutes. Sometimes the sonographer needs you to move or come back later if your baby is in an awkward position.
Many hospitals can tell you your baby's sex at this scan if you'd like to know — say so at the start. Some hospitals have a policy not to, so do check.
💬Questions worth asking
- Is everything measuring as expected?
- Where is my placenta lying?
- Would you be able to tell us the baby's sex?
Good to know. If the scan finds something, it doesn't always mean a problem — it often just means more information is needed. Your team will explain any next steps clearly.
Sources:
www.nhs.uk