When do i have a dating scan

Unless there are concerns about the pregnancy it is better to wait to have this scan after 7 weeks as the images are clearer for you to see and better for us to measure. If you come before 7 weeks the baby will be less than 1cm in size and so the scan sometimes has to be performed transvaginally placing the probe inside the vagina to enable us to see the baby well enough to measure and to see the heartbeat. We ask that you come with a full bladder for this scan as it usually allows us to get the best possible picture of the baby. If you decide to go ahead with this optional screening test you will be offered a scan between 11 weeks 2 days and 13 weeks 6 days ideally 12 weeks.

Back to Your pregnancy and baby guide. All pregnant women in England are offered an ultrasound scan at around 8 to 14 weeks of pregnancy. This is called the dating scan. It's used to see how far along in your pregnancy you are and check your baby's development. Your midwife or doctor will book you a dating scan appointment.

Melissa Maimann July 03, When is the best time in pregnancy to get an accurate dating scan? Our midwife explains.

As its name suggests, the main purpose of a dating scan is to check how advanced the pregnancy is and therefore when the baby is due. Measuring the baby can be more accurate than dating by the last menstrual period. It is also an opportunity to check the baby is alive and developing as expected, and check for twins. This scan may also be part of your screening test for Down's syndrome nuchal translucency scan.