The earlier the ultrasound is done, the more accurate it is at estimating the babys due date. Ultrasounds performed during the first 12 weeks of pregnancy are generally within 3 - 5 days of accuracy. The most accurate time is between 8 and 11 weeks gestation.

Can 12-week scan be done at 11 weeks?

The nuchal translucency scan is best done during the 12th week, but it can be done from 11 weeks and 3 days up until 14 weeks and your local NHS hospital will offer you an appointment to have this done at around this time. Nevertheless, some parents may opt to have this done privately instead.