Obstetrics• Updated 21 October 2026
Anomaly Scan (Level II Scan)
A detailed scan at 18–22 weeks of pregnancy that checks the baby's organs and development.
Results: Same day
Quick Summary
Primary Purpose
To look for structural problems in the baby's brain, heart, spine, kidneys and limbs.
What It Measures
Baby's anatomy, growth, placenta and fluid.
Preparation
No special preparation.
Overview
The anomaly scan can find many, but not all, problems.
If something is found, you'll be offered more tests and specialist advice.
What It Measures
Organs
Brain, heart, spine, kidneys, limbs.
Placenta and fluid
Position and amount.
How It's Performed
- 01
Timing
Between 18 and 22 weeks.
- 02
Scan
Takes about 30–45 minutes.
- 03
Follow-up
Explained by the sonologist or doctor.
Sources and further reading
Last updated 21 October 2026. For more detail, see these trusted health organisations.
- Ultrasound(opens in a new tab) · MedlinePlus, US National Library of Medicine
- 20-week scan(opens in a new tab) · NHS