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EDD Calculation Formula:
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The EDD (Estimated Due Date) From Conception Day calculation estimates the expected delivery date by adding 266 days to the known conception date. This method provides a precise due date calculation when the exact conception day is known.
The calculator uses the simple formula:
Where:
Explanation: This calculation assumes a standard 266-day gestation period from conception to birth, which corresponds to 38 weeks of pregnancy.
Details: Accurate due date calculation is crucial for prenatal care planning, monitoring fetal development, preparing for delivery, and scheduling important medical tests and appointments throughout pregnancy.
Tips: Enter the exact conception date in the date picker. The calculator will automatically compute the estimated due date by adding 266 days to the provided conception date.
Q1: Why 266 days specifically?
A: 266 days represents the average gestation period from conception to delivery, which equals 38 weeks of pregnancy.
Q2: How accurate is this calculation method?
A: When the exact conception date is known, this method is very accurate. However, only about 5% of babies are born exactly on their due date.
Q3: What if I don't know my exact conception date?
A: If conception date is unknown, use the last menstrual period (LMP) method which adds 280 days (40 weeks) to the first day of your last period.
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 initial calculation.
Q5: What is considered full term pregnancy?
A: Full term is between 39 weeks 0 days and 40 weeks 6 days. Babies born between 37 weeks 0 days and 38 weeks 6 days are considered early term.