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EDD Calculation Formula:
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The Pregnancy Calculator estimates the due date based on the last day of your menstrual period using the standard 280-day pregnancy duration calculation method.
The calculator uses the standard EDD formula:
Where:
Explanation: This calculation assumes a regular 28-day menstrual cycle and adds 280 days (40 weeks) to the first day of your last menstrual period to estimate the due date.
Details: Accurate due date estimation is crucial for proper prenatal care, monitoring fetal development, planning for delivery, and ensuring the health of both mother and baby throughout pregnancy.
Tips: Enter the exact date of the last day of your menstrual period. Ensure the date is accurate for the most reliable due date estimation. This method works best for women with regular menstrual cycles.
Q1: How accurate is this calculation method?
A: This method provides a good estimate but may vary based on individual cycle length and ovulation timing. Ultrasound dating is often more precise.
Q2: What if my menstrual cycle is irregular?
A: For irregular cycles, this calculation may be less accurate. Consult with your healthcare provider for a more precise due date determination.
Q3: Why 280 days instead of 9 months?
A: Pregnancy is calculated as 40 weeks from the last menstrual period, which equals 280 days, rather than calendar months which vary in length.
Q4: Can the due date change during pregnancy?
A: Yes, healthcare providers may adjust the due date based on ultrasound measurements, especially if there's a significant difference from the LMP-based calculation.
Q5: What percentage of babies are born on their due date?
A: Only about 5% of babies are born exactly on their due date. Most births occur within two weeks before or after the estimated due date.