1. What is Ultrasound Gestational Age?

Ultrasound gestational age is the estimated age of pregnancy measured through ultrasound examination. It provides accurate dating of pregnancy based on fetal measurements and development.

2. How Does the Calculator Work?

The calculator uses ultrasound measurements to determine gestational age:

Where:

• \( Ultrasound\ Measurement \) — Weeks determined from ultrasound examination

Explanation: Ultrasound dating is most accurate in early pregnancy and provides reliable gestational age assessment throughout pregnancy.

3. Importance of Ultrasound Dating

Details: Accurate gestational age determination is crucial for monitoring fetal development, scheduling prenatal tests, determining due date, and managing high-risk pregnancies.

4. Using the Calculator

Tips: Enter the gestational age in weeks as measured by ultrasound. Valid range is typically 5-42 weeks of pregnancy.

5. Frequently Asked Questions (FAQ)

Q1: How accurate is ultrasound dating?
A: Ultrasound dating is most accurate in the first trimester (±5-7 days) and becomes less precise as pregnancy progresses.

Q2: What measurements are used for ultrasound dating?
A: Crown-rump length (CRL) in first trimester, biparietal diameter (BPD), head circumference (HC), abdominal circumference (AC), and femur length (FL) in later trimesters.

Q3: When is the best time for dating ultrasound?
A: Between 8-13 weeks gestation provides the most accurate dating using crown-rump length measurement.

Q4: Can ultrasound dating change my due date?
A: Yes, if there's a significant difference (>7 days) between LMP dating and ultrasound dating in first trimester, the ultrasound date is typically used.

Q5: What if ultrasound shows different gestational age than my LMP?
A: Ultrasound dating is generally more reliable than last menstrual period (LMP) dating, especially if the ultrasound is performed in the first trimester.