If you choose to have a dating scan, it will most probably be your first scan. You will need to get a referral from your doctor or midwife for a dating scan. Most women can instead have their first scan at 11 to 13 weeks — this is usually called the 12-week scan.

How accurate is the 12 week scan for dating?

How accurate is the ultrasound examination? 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 you see a bump at 12 weeks?

If its your first pregnancy youll probably start to show between 12 to 16 weeks. But this initial bump is not from the baby. In fact, at 15 weeks, the average fetus is 4 inches long, or about as large as an orange.