A dating ultrasound or dating scan is a scan done early in pregnancy (before 12 weeks). It is usually done to check how many weeks pregnant you are and therefore to calculate the estimated due date, but it can be done for other reasons. • Only a few women need a dating scan.

How is a dating scan performed?

A dating scan is carried out by ultrasound. A sonographer, who is usually a radiographer or a midwife trained in ultrasound, will complete your scan. If the scan is after 10 weeks, ultrasound recordings are usually made through your abdomen.