What should you know about growth scan in which week?

Growth scans are often arranged later in pregnancy, but there is no single week that suits everyone. Your clinician considers the first day of your last period, dating scan, previous growth pattern, pregnancy conditions, placenta findings and whether you are expecting more than one baby. The timing is chosen so the measurements answer a practical question and can be compared with earlier information.

Sometimes a scan is repeated after an interval to see the direction of growth. A result is interpreted with fluid volume, Doppler blood flow, movements and your clinical examination rather than by one number alone.

Check the date, location and whether the service has preparation instructions. Bring your maternity records and tell the team about any new symptoms or changes in movement. At the visit, ask who will discuss the findings and when. If you cannot attend, contact the maternity service promptly so a clinically suitable appointment can be arranged.

Do not move or cancel the scan based on an online calendar. The right timing may be different when the purpose is routine monitoring, checking a previous concern or deciding whether another assessment is needed.

Seek maternity advice immediately for reduced fetal movements, bleeding, leaking fluid, painful regular contractions or severe abdominal pain. Severe headache, visual disturbance, chest pain, breathlessness, or sudden swelling with feeling unwell also needs prompt assessment. These concerns should be assessed when they occur, regardless of the planned scan week.

Ask why this week was selected, what the scan is intended to assess, whether another scan may be needed, and how the result could affect monitoring. Confirm the route for urgent advice between appointments.