How accurate is 12 week dating scan
See What if a screening test shows a possible problem?
for more information on what may happen if a scan or other screening test suggests an abnormality.
There are no known risks to the baby or the mother from having an ultrasound scan, but it is 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.
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.
For example, you may be offered further tests, such as amniocentesis, that have a risk of miscarriage.
The first scan is sometimes called the dating scan.
Having a scan in pregnancy is usually a happy event, but be aware that ultrasound scans may detect some serious abnormalities, so try to be prepared for that information.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.Some women may be offered more than two scans, depending on their health and their pregnancy.You can find out more about the dating scan and the anomaly or mid-pregnancy scan. Some people want to find out if their baby has problems, while others don't.