12 weeks scan

The 12 week scan or dating scan is definitely one of the most exciting moments for a future mum.

Until now, your life hasn't changed that much. Sure, you've been dealing with annoying pregnancy symptoms, but at first sight you don't yet appear to be pregnant. Well, this is about to change when you have the 12 week ultrasound. Symptoms aside, this will be the first time that you'll see your baby-to-be growing inside your womb, and how amazing is that? 

Prepare for such thrilling pregnancy milestone by taking a look at the following article, where you'll find all the information and tips about the dating scan.

When will you have the 12 week scan?

The name 12 weeks scan is actually a bit of a misnomer because they don’t always happen by the time you’re 12 weeks pregnant. Typically, they will take place between 11 weeks pregnant and 14 weeks pregnant, but there are also other factors that can affect exactly when you will have yours. First, if your pregnancy is going smoothly without any bad side effects like pain or bleeding, or a history of difficult pregnancies, your doctor will probably follow a normal schedule. However, if there are problems, they could choose to do this first pregnancy scan early, just to check in on your little one.

After the 12 week scan or dating scan, you will be expected to have a second ultrasound, called the anomaly scan, at 20 weeks pregnant. As its name indicates, this one will help the doctor look for any abnormalities in the baby's development. Finally, you could be offered a third ultrasound from 28 weeks pregnant to 40 weeks pregnant, in case you had undergone difficulties in past pregnancies, such as having a smaller foetus than normal or getting gestational diabetes. And if you want to see your baby once again, ask your doctor or midwife about the 4D scan!


What will the 12 week scan be like and what will I see?

When you have your first pregnancy scan, you will probably be very excited to get a first glimpse at your little one! The procedure is easy and painless. You will simply lie on the doctor’s table while the sonographer uses a special hand-held scanner to look through your tummy into your uterus. In some cases, you may need to have a vaginal scan instead, but it still shouldn’t hurt.

Usually the sonographer will let the mummy and daddy watch the whole process on a screen. The image of the 12 week scan will look a lot like an X-Ray, all in black and white. You’ll see mostly black, which will be your uterus and the amniotic fluid. To the untrained eye, your baby will probably just look like little grey blobs. But the doctor and sonographer know exactly what they are looking at: a head, arms and legs, some organs, and a beating heart.

The size of your growing little one will help the doctors determine more accurately how far along you are in your pregnancy. Here are the average sizes that can be expected in the 12 week scan:

  • 10 weeks: 1.2 inches
  • 11 weeks: 1.3 – 1.9 inches
  • 12 weeks: 2 – 2.5 inches
  • 13 weeks: 2.6 – 2.9 inches


What information is the doctor looking for in the 12 week scan?

As suggested by the name “dating scan,” the most important piece of information the sonographer wants to find out is your due date. In addition to the size of the foetus, the doctors will listen to the heart, look at the brain and other organs, and check for general growth and development. They will also look at the size and location of your placenta in order to make sure that your baby is growing in the proper place in your body.

It has become fairly common for medical centres to offer screening tests for Down syndrome at the same time as the first pregnancy scan. As explained thoroughly in our article about nuchal translucency, this is a simply test that measures the amount of fluid at the base of your baby’s skull, just where it meets the spine. Excess fluid is a common indicator of Down syndrome.

Besides looking for indications of Down syndrome, doctors will not be focused on looking for abnormalities or developmental problems. A more thorough check-up will take place during your next pregnancy scans, which you can read about in our article on the 20 week scan.


What if there are problems?

Sadly, the results of a 12 week scan don't always turn well. You need to be prepared for any complication, accept it and get ready to look for second opinions. The 12 week ultrasound isn't 100% accurate, so if the sonographer spots a problem, he'll schedule you an appointment with a fetal medicine consultant. He or she will be the one to confirm whether the foetus shows any abnormality and how to take care about it for the rest of your pregnancy.


How much does the 12 week scan cost?

Like all medical procedures, the cost of the 12 weeks scan will depend on where you live and what kind of healthcare coverage you have. In the UK, all necessary pregnancy related tests are 100% covered by NHS. If you live outside of the UK, you will have to ask your healthcare provider how much it will cost in your specific case.

Typically the medical centre will provide you with a couple of black and white images of the scan, but many offer the option of purchasing additional images, video, or a CD Rom copy for a few pounds.


In general, you don't have much to worry about before getting the 12 week scan. It isn't harmful for either you or the baby, and it provides your doctor with vital information about the state of your pregnancy. Also, it is an emotional experience, since you'll get your first glimpse of your little one. Enjoy it and don't be nervous, because it will most likely be alright.