Anomaly / Level II Assessment

The anomaly scan is the most detailed structural review carried out during pregnancy. The baby's anatomy is examined in a defined sequence, and measurements are taken to assess growth.

It takes longer than most scans, and a doctor may pause and return to a view if the baby is not in a helpful position.

The head and brain, face, spine, chest and heart, abdomen and abdominal wall, kidneys and bladder, and the limbs — together with the placenta, the umbilical cord and the volume of amniotic fluid.

Growth measurements are taken and compared against the expected range for the stage of pregnancy.

A detailed scan can identify many structural differences, but it cannot identify all of them. Some conditions are not visible on ultrasound, some develop later in pregnancy, and some are only recognised after birth.

How much can be seen also depends on the baby's position, the stage of pregnancy and imaging conditions on the day. A normal anomaly scan is reassuring, but it is not a guarantee.

If some views could not be completed, a repeat appointment may be suggested purely to finish the review — this is common and is not in itself a cause for concern.

Where a finding needs a closer look, your doctor may advise a focused assessment such as a fetal cardiac scan, or a discussion about further testing.

Findings are reported to you and to your treating doctor, who advises on any next step.