You are here: Home » My Pregnancy » Ultrasound Scans in Pregnancy
Find out about ultrasound baby scans, including the dating scan and anomaly scan, to check for abnormalities in the baby during pregnancy.
Ultrasound scans use sound waves to build a picture of the baby in the womb. The scans are painless, have no known side effects on mothers or babies, and can be carried out at any stage of pregnancy. Talk to your midwife, GP or obstetrician about any concerns you have.
Having a scan in pregnancy is usually a happy event, but be aware that ultrasound scans may detect some serious health conditions, so try to be prepared for that information.
See What if a screening test finds something for more information on if a scan or other screening test suggests your baby may be more likely to have a condition.
Most scans are carried out by sonographers. The scan is carried out in a dimly lit room so the sonographer is able to get good images of your baby.
You'll be asked to lie on your back and reveal your tummy.
The sonographer will put ultrasound gel on your tummy, which makes sure there is good contact between the machine and your skin.
The sonographer passes a probe over your tummy and a picture of the baby will appear on the ultrasound screen.
During the exam, sonographers need to keep the screen in a position that gives them a good view of the baby.
The sonographer will carefully examine your baby's body. The sonographer may need to apply slight pressure on your tummy to get the best views of the baby.
A scan usually takes around 20 to 30 minutes. However, the sonographer may not be able to get good views if your baby is lying in an awkward position or moving around a lot.
If it's difficult to get a good image, the scan may take longer or have to be repeated at another time.
There are no known risks to the baby or the mother from having an ultrasound scan, but it's important that you consider carefully whether to have the scan or not.
This is because the scan can provide information that may mean you have to make further important decisions. For example, you may be offered further tests, such as amniocentesis, that have a risk of miscarriage.
Hospitals in England offer at least 2 ultrasound scans during pregnancy:
The first scan is sometimes called the dating scan. The sonographer estimates when your baby is due (the estimated date of delivery, or EDD) based on the baby's measurements.
The dating scan can include a nuchal translucency (NT) scan, which is part of the combined screening test for Down's syndrome, if you choose to have this screening.
The second scan offered during pregnancy usually takes place between 18 and 21 weeks of pregnancy. It's sometimes called the mid-pregnancy scan. This scan checks for 11 physical conditions in your baby.
You may be offered more than 2 scans, depending on your health and the pregnancy. You can find out more about the 12-week dating scan and the 20-week or mid-pregnancy scan.
The sonographer will be able to tell you the results of the scan at the time.
No, not if you do not want to. Some people want to find out if their baby is more likely to have a condition, while others do not. The 12-week dating scan and 20-week scan will be offered to you, but you do not have to have them.
Your choice will be respected if you decide not to have the scans, and your antenatal care will continue as normal. You'll be given the chance to discuss it with your maternity team before making your decision.
An ultrasound scan can be used to:
Yes. You may like someone to come with you to the scan appointment.
Most hospitals do not allow children to attend scans as childcare is not usually available. Please ask your hospital about this before your appointment.
Remember, an ultrasound scan is an important medical examination and it is treated in the same way as any other hospital investigation. Ultrasound scans can sometimes find problems with the baby.
Most scans show that the baby is developing normally and no problems are found. This is because most babies are healthy. You can continue with your routine antenatal care.
If the scan shows your baby is more likely to have a condition, the sonographer may ask for a second opinion from another member of staff. You might be offered another test to find out for certain if your baby has the condition.
If you're offered further tests, you will be given more information about them so you can decide whether or not you want to have them. You'll be able to discuss this with your midwife or consultant.
If necessary, you will be referred to a specialist, possibly in another hospital.
Finding out the sex of your baby is not offered as part of the national screening programme.
If you want to find out the sex of your baby, you can usually do so during the 20-week mid-pregnancy scan but this depends on the policy of your hospital. Tell the sonographer at the start of the scan that you'd like to know your baby's sex.
Be aware, though, that it's not possible for the sonographer to be 100% certain about your baby's sex. For example, if your baby is lying in an awkward position, it may be difficult or impossible to tell.
Some hospitals have a policy of not telling patients the sex of their baby. Speak to your sonographer or midwife to find out more.
You will need to check if your hospital provides this service. If they do, there may be a charge.
It's important to continue taking any medication prescribed unless your GP/specialist specifically tells you to stop. Please visit our Existing Health Conditions page for more information, or visit 'Bumps' ('Best Use of Medicines in Pregnancy').
Your choices will be saved as a non-identifying cookie. This means that each time you load a webpage from this website, your chosen accessibility options will be applied. These cookies will last for 28 days before resetting.
When text to speech is active, you can click the play button to hear the whole sites content read aloud. You can also highlight a section of text and press play, to hear only the highlighted text.
Choose a language from the Google provided selector below.
A screen mask is a reading tool which follows your cursor. It allows you to remove distractions from around the page and gives a clear area of focus.
Use these icons to increase, decrease or reset the size of the text throughout the site.
Change the colour of text and the background of the site with the selectors below. This removes images and makes the content across the site easier to read.