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Due Date Calculation Formula:
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The Pregnancy Calculator Due Date Based On Conception estimates the expected delivery date by adding 266 days to the known conception date. This method provides an accurate due date calculation when the exact conception date is known.
The calculator uses the following formula:
Where:
Explanation: This calculation assumes a standard 266-day gestation period from conception to delivery, which corresponds to approximately 38 weeks of pregnancy.
Details: Accurate due date calculation is essential for proper prenatal care, monitoring fetal development, planning for delivery, and ensuring the health of both mother and baby throughout the pregnancy.
Tips: Enter the exact conception date in the date field. The calculator will automatically compute the estimated due date by adding 266 days to the provided conception date.
Q1: Why 266 days instead of 280 days?
A: 280 days is calculated from the first day of the last menstrual period (LMP), while 266 days is from the actual conception date, accounting for the typical 2-week difference.
Q2: How accurate is this calculation method?
A: When the exact conception date is known, this method is highly 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 the conception date is unknown, use the last menstrual period (LMP) method which adds 280 days to the first day of your last period.
Q4: Can due dates change during pregnancy?
A: Yes, healthcare providers may adjust the due date based on ultrasound measurements, especially if there's a significant discrepancy from the initial calculation.
Q5: What factors can affect the actual delivery date?
A: Maternal health, fetal development, multiple pregnancies, and various medical conditions can influence when delivery actually occurs.