Growth Scans in Pregnancy: When They're Needed & Cost

A growth scan is a third-trimester ultrasound that measures your baby - head, abdomen, and thigh bone - to estimate size and weight, and checks the amniotic fluid and placenta.

Unlike the dating and morphology scans, growth scans aren't routine for every pregnancy in Australia. They're ordered when your doctor or midwife has a specific reason to keep a closer eye on things.

Common reasons include:

• Your bump measuring smaller or larger than expected for your dates • Gestational diabetes • High blood pressure or pre-eclampsia monitoring • Twins or other multiples • A low-lying placenta at the morphology scan - usually rechecked around 32 weeks • Reduced baby movements • A previous small or large baby

Being sent for a growth scan is common and usually precautionary - it's your care team gathering information, not a diagnosis.

Doppler is an ultrasound technique - often part of a growth or wellbeing scan - that measures blood flow, most commonly in the umbilical cord. It helps your care team check that the placenta is supplying your baby well, and is completely painless with no radiation, like all ultrasound.

Almost nothing to do:

• No full bladder is usually needed in the third trimester - follow your clinic's instructions when you book. • Wear comfortable, two-piece clothing. • Bring your referral, Medicare card, and previous pregnancy scan reports so the sonographer can compare growth over time.

With a valid referral and Medicare card:

• Bulk billed: many radiology clinics bulk bill growth scans - no out-of-pocket cost. • Private fees: where a gap is charged, it's commonly in the range of $100-$250 after the Medicare rebate.

If you need repeat growth scans - for example fortnightly monitoring - gaps add up quickly, so it's especially worth finding a bulk-billing clinic. Radly shows prices and bulk-billing status side by side.

The measurements are plotted against your baby's earlier scans, and a report goes to your referring doctor or midwife - who will explain the trend, not just a single number, and whether any further monitoring is recommended.

See where growth scans fit in the full pregnancy scan timeline.