Most pregnancies include at least two routine ultrasound scans. Some people have extra scans if there is a medical reason. Here is when each main scan usually happens.
Early pregnancy scan (6 to 10 weeks)
Not everyone has this scan. It may be offered if you have bleeding, pain, a previous ectopic pregnancy or fertility treatment. It confirms where the pregnancy is and whether a heartbeat can be seen.
Dating scan (about 8 to 14 weeks)
This scan measures the baby to work out how many weeks pregnant you are and set your due date. It also checks how many babies there are. ACOG considers a first-trimester ultrasound the most accurate way to date a pregnancy.
NT scan (11 to 14 weeks)
The nuchal translucency (NT) scan measures fluid at the back of the baby’s neck. Combined with a blood test, it estimates the chance of conditions such as Down syndrome. It is often done at the same visit as the dating scan. Screening is optional.
Anomaly scan (18 to 22 weeks)
This detailed scan looks at the baby’s organs, bones and growth, and checks the placenta. In the UK it is offered between 18 and 21 weeks. You may be able to find out the baby’s sex if you wish.
Growth scans (third trimester)
Extra scans later in pregnancy are not routine for everyone. They may be offered if your bump measures small or large, if you have a condition such as diabetes or high blood pressure, or if you are expecting twins.
Is ultrasound safe?
Medical ultrasound has been used in pregnancy for decades and is considered safe when done by trained professionals for a medical reason.
Had your dating scan? Get your due date from it with our Ultrasound Due Date Calculator.