1. What is Gestational Age?

Gestational age refers to the duration of pregnancy measured from the first day of the last menstrual period or conception date. It is typically expressed in completed weeks and is crucial for monitoring fetal development and determining appropriate prenatal care.

2. How Does the Calculator Work?

The calculator uses the gestational age formula:

Where:

• \( GA \) — Gestational age in weeks
• \( CD \) — Current date
• \( CPD \) — Conception date
• \( \lfloor \rfloor \) — Floor function (rounding down to nearest integer)

Explanation: The formula calculates the number of complete weeks between the conception date and current date by dividing the total days by 7 and rounding down to the nearest whole number.

3. Importance of Gestational Age Calculation

Details: Accurate gestational age calculation is essential for determining fetal growth milestones, scheduling prenatal tests, estimating due dates, and making critical decisions about pregnancy management and delivery timing.

4. Using the Calculator

Tips: Enter the current date and conception date in the format YYYY-MM-DD. Ensure the conception date is earlier than the current date. The calculator will automatically compute the gestational age in completed weeks.

5. Frequently Asked Questions (FAQ)

Q1: What is the difference between gestational age and fetal age?
A: Gestational age is measured from the first day of the last menstrual period or conception, while fetal age is measured from the actual time of fertilization, typically about 2 weeks less than gestational age.

Q2: How accurate is this calculation method?
A: This method provides a basic calculation of completed weeks. For clinical purposes, ultrasound measurements in early pregnancy provide the most accurate gestational age assessment.

Q3: What if I only know the last menstrual period date?
A: If using last menstrual period, add approximately 14 days to get an estimated conception date, as conception typically occurs about 2 weeks after the start of the last menstrual period.

Q4: Why use floor function instead of rounding?
A: The floor function ensures that only completed weeks are counted, which is the standard practice in obstetric dating to avoid overestimating gestational age.

Q5: Can this calculator be used for IVF pregnancies?
A: For IVF pregnancies, use the embryo transfer date as the conception date and add the appropriate number of days based on whether it was a day 3 or day 5 embryo transfer.