Growth scans around seven months of pregnancy

The sonographer measures parts of the baby's head and abdomen and the length of a thigh bone. Software combines these measurements to estimate size; it is an estimate rather than a direct weight. The scan may also record the baby's position, movements, amniotic fluid and placental location. In some circumstances, blood-flow measurements are added. A single value is interpreted alongside the pregnancy dates, earlier scans and the pattern seen over time.

Follow the appointment instructions about drinking water and bring your maternity notes or previous scan information if requested. Wear clothing that allows easy access to the abdomen. During the visit, tell the team about changes in fetal movement, bleeding, fluid leakage, contractions or new health concerns. If measurements differ from the expected pattern, the next step may be a repeat scan, additional monitoring or a review by the maternity team; one scan result does not by itself explain the cause.

Contact your maternity unit promptly if your baby's movements are reduced or have changed from their usual pattern. Seek urgent assessment for vaginal bleeding, suspected leaking of fluid, regular painful contractions, severe abdominal pain, a severe or persistent headache, visual disturbance, sudden marked swelling, chest pain, difficulty breathing, fainting or feeling seriously unwell. Do not wait for a booked ultrasound to discuss these symptoms.

Ask how the measurements compare with your earlier scans and whether the overall pattern is reassuring. Clarify whether the amniotic fluid, placenta and any blood-flow assessment need follow-up. If another appointment is recommended, ask what it is intended to check, when it should happen and whether you need other monitoring between visits. Also confirm how to contact the maternity unit if fetal movements change.