How do I use the Due Date By Ultrasound Calculator?
Enter the date of your ultrasound and the crown-rump length (CRL) in centimeters. The calculator will then estimate your due date based on these inputs.
What is crown-rump length (CRL)?
Crown-rump length is the distance from the top of the fetus’s head to the bottom of its buttocks, measured during an ultrasound. It helps determine gestational age.
Why is the CRL important for calculating the due date?
CRL is crucial because it provides a direct measurement of fetal growth, allowing healthcare professionals to estimate the gestational age and, consequently, the due date with high accuracy.
What if my ultrasound measurement is in millimeters? How should I input it?
Convert your CRL measurement from millimeters to centimeters by dividing by 10 before entering it into the calculator.
Can this calculator be used for all pregnant women?
This calculator is most accurate for early pregnancy, typically up to about 20 weeks gestation. It may not be as reliable after that point.
How does the calculator estimate the due date?
The calculator uses the formula: Due Date = Date of Ultrasound + (40 – CRL/2.5) * 7 days, where CRL is in centimeters. This accounts for the average duration of pregnancy.
What should I do if my due date changes after the initial ultrasound?
If your due date changes, simply update the calculator with the new ultrasound date and CRL measurement to get an updated estimate.