Due Date Accuracy Evidence suggests that, in the first 20 weeks of pregnancy, the first ultrasound may be the most accurate tool for calculating a fetuss gestational ages. If you cant remember the date of your last menstrual period date, an early ultrasound can give you a fairly reliable due date.

How accurate is first ultrasound due date?

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.

Does ultrasound determine due date?

If you have more ultrasounds, each ultrasound report will contain a new due date based on the most recent measurements. An expected due date shouldnt be changed based on measurements from a second- or third-trimester ultrasound. Due date estimations are more accurate earlier in pregnancy.

Do you find out your due date at your first appointment?

Estimating Your Due Date At your first prenatal exam, your health care provider will ask questions to try to predict your due date as precisely as possible. Knowing your babys due date will help your provider monitor your babys growth more accurately.

How far along are you when you get your first ultrasound?

A first-trimester ultrasound is usually done 7 to 8 weeks from the first day of your last menstrual period, says Rebecca Jackson, MD, assistant professor of obstetrics and gynecology at the Sidney Kimmel Medical College at Thomas Jefferson University in Philadelphia, PA.