What should you know about a USS growth scan?

USS is shorthand for ultrasound scan. The appointment gives your maternity team information to combine with your dates, symptoms and other checks.

You generally lie comfortably while gel and an ultrasound probe are used over the abdomen. The sonographer records images and may measure the baby's head, abdomen and thigh bone. These measurements help estimate size and identify a pattern that may need watching. The scan can also assess heartbeat, movement, presentation, placenta location and amniotic fluid.

Sometimes Doppler ultrasound is used to assess blood flow. This is decided according to your pregnancy and the reason for the scan. The report is not interpreted in isolation, and an estimated size is not a direct measurement of the baby's weight.

Read the appointment instructions carefully because bladder requirements can vary. Wear a two-piece outfit and bring your maternity information. Tell the team about pain, bleeding, leaking fluid, changes in movement or any medical condition. Before leaving, check whether the result will be explained immediately or shared at a later visit, and write down any recommended follow-up.

Contact your maternity service without waiting for the scan if fetal movements are reduced or noticeably different, or if you have bleeding, fluid loss, regular painful contractions, severe abdominal pain, severe headache or vision changes. Seek emergency care for heavy bleeding, fainting, breathing problems or severe illness. A normal appointment cannot rule out a later change.

Ask what growth trend is being followed, whether fluid and placental findings are reassuring, whether blood-flow measurements were needed, and what would trigger another scan. Confirm the telephone number to use if movement changes.