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Pregnancy Due Date Calculation:
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Pregnancy cycle calculation estimates the due date of a pregnancy based on the first day of the last menstrual period (LMP). The standard calculation adds 280 days (40 weeks) to the LMP date to determine the expected delivery date.
The calculator uses the standard pregnancy calculation formula:
Where:
Explanation: This calculation is based on Naegele's rule, which assumes a 28-day menstrual cycle with ovulation occurring on day 14.
Details: Accurate due date estimation is crucial for proper prenatal care, monitoring fetal development, planning for delivery, and identifying potential pregnancy complications.
Tips: Enter the first day of your last menstrual period. The calculator will determine your due date and current pregnancy week. For irregular cycles, consult with a healthcare provider for a more accurate estimation.
Q1: How accurate is the 280-day calculation?
A: While 280 days is the average, only about 5% of women deliver exactly on their due date. Most deliveries occur within two weeks before or after the calculated date.
Q2: What if I have irregular periods?
A: For women with irregular cycles, an early ultrasound provides a more accurate due date estimation than LMP-based calculation.
Q3: Does this calculation work for IVF pregnancies?
A: For IVF pregnancies, the embryo transfer date is typically used instead of LMP for more accurate dating.
Q4: Why is pregnancy calculated from LMP rather than conception?
A: LMP is used because most women can recall their last period date more accurately than conception date.
Q5: When should I confirm my due date with a healthcare provider?
A: You should schedule your first prenatal appointment within the first 8 weeks of pregnancy to confirm dating and begin proper prenatal care.