What to expect: first trimester ultrasounds

Young couple with their first baby ultrasound

There’s nothing quite like seeing your baby for the first time, and just a few weeks into your pregnancy you’ll get the chance to view your little bean on an ultrasound.

Depending on how early your doctor recommends your first ultrasound, it will be either a transabdominal ultrasound or a transvaginal ultrasound. If you’re unsure of your dates, your doctor may recommend a dating ultrasound to get a more accurate indication of how far along you are. Other reasons for a dating ultrasound include making sure the pregnancy is not ectopic and of course checking how many babies you’re having.

Here’s what to expect from first trimester ultrasounds:

Internal ultrasound

If you’re less than eight weeks pregnant and your doctor has requested an early ultrasound, it will most likely be a transvaginal, or internal ultrasound. It involves the use of a probe inserted into the vagina, which can capture clearer images in early pregnancy.

Transabdominal ultrasound

If you’re eight weeks or more, you will likely have a transabdominal ultrasound – which involves scanning your lower belly.

Generally, you’ll be asked to have a comfortably full bladder when having this ultrasound to allow the sonographer to better see your baby and organs.

Combined screening test

Somewhere between your 10th and 12th week of pregnancy, you’ll have a blood test, followed by an ultrasound between 11 and 13 weeks. This is sometimes called the nuchal translucency ultrasound, nuchal scan or NT scan.

When these tests are combined, it will indicate the chances of your baby being born with certain chromosomal abnormalities, including Down syndrome or Trisomy 18. The test won’t tell you if your baby has Down syndrome, it will tell you if your risk is high or low.

If your combined screening returns a high risk, you will also be offered an additional test, either a CVS (Chronic Villus Sampling) or amniocentesis. A CVS is usually carried out between 11 and 14 weeks but can be done later, and includes a small sample being taken from the placenta.

What your baby looks like on an ultrasound

9 week baby ultrasound photo

5 to 6 weeks: baby is a teeny tiny embryo, just a few millimetres long. You may not see the embryo you probably will see the sack. It’s normal not to hear a heartbeat at this stage.

6 to 7 weeks: baby is measuring about five to nine millimetres. and the heartbeat can be detected.

8 to 10 weeks: by this stage, you should be able to see your baby on a transabdominal ultrasound.

11 to 12 weeks: there’s a baby! An ultrasound at this stage will show a fully formed baby with a head, body, arms and legs. You may even see babe wriggling around.