12-Week Scan (Nuchal Translucency): What to Expect & Cost

The nuchal translucency (NT) scan is an ultrasound done between 11 weeks and 13 weeks 6 days. The sonographer measures a small pocket of fluid at the back of your baby's neck - the nuchal translucency - along with your baby's growth and early anatomy.

Combined with a blood test and factors like your age, the measurement estimates the chance of certain chromosomal conditions such as trisomy 21 (Down syndrome). This combination is called combined first-trimester screening.

No. Screening is a choice, and plenty of parents decide differently - some have the full combined screening, some choose NIPT instead, some have the scan mainly to check on their baby's development, and some skip screening altogether.

Your GP, obstetrician, or midwife will talk you through the options so you can decide what's right for you. There's no wrong answer.

They test in different ways:

• The NT scan is an ultrasound measurement, combined with a blood test, that estimates chance - it doesn't give a yes/no answer. It also physically checks your baby's growth and early anatomy, which a blood test can't do. • NIPT (non-invasive prenatal testing) analyses fragments of the baby's DNA in your blood from about 10 weeks. It's more sensitive for the common trisomies, but it's a lab test - no pictures, no anatomy check - and currently has no Medicare rebate, so it costs a few hundred dollars out of pocket.

Many parents who have NIPT still have an ultrasound around 12-13 weeks to check the baby itself. Which path to take is a conversation for your care provider.

Preparation is simple:

• Your clinic may ask for a moderately full bladder - follow their exact instructions when you book. • Wear comfortable, two-piece clothing so your belly is easy to access. • Bring your referral, Medicare card, and any previous pregnancy scans.

If you're having combined screening, the blood test is usually taken from about 10 weeks - your referrer will arrange the timing so the results come together.

With a valid referral and Medicare card:

• Bulk billed: available at some radiology clinics - no out-of-pocket cost. • Private fees: specialist obstetric imaging practices commonly charge a gap of roughly $100-$250 after the Medicare rebate for an NT scan.

If you have NIPT as well, that's a separate lab fee with no Medicare rebate. Comparing imaging clinics before you book can meaningfully cut the scan side of the cost - Radly shows prices and bulk-billing side by side.

The nuchal translucency measurement is only meaningful while your baby is within a specific size range, which corresponds to 11 weeks - 13 weeks 6 days. Outside that window the measurement can't be interpreted reliably, and the screening calculation can't be done.

That's why clinics ask your dates carefully when you book - and why it's worth booking this scan as soon as your dating scan confirms them. If the window is missed, your doctor will talk to you about second-trimester screening options instead.

A specialist reviews the images and your referring doctor or midwife receives the report, usually alongside your blood test results if you're having combined screening. They'll explain what the results mean - remember screening estimates chance; it doesn't diagnose.

Your next routine scan is the morphology scan at 18-22 weeks. See the full pregnancy scan timeline.