1. What is the Pregnancy Due Date Calculator?

The Pregnancy Due Date Calculator estimates the expected delivery date (EDD) based on the conception date. It uses the standard medical calculation of 266 days (38 weeks) from conception to estimated delivery.

2. How Does the Calculator Work?

The calculator uses the following formula:

Where:

• 266 days represents the typical gestation period from conception to delivery
• This is equivalent to 38 weeks of gestation

Note: The more commonly known "40 weeks" pregnancy duration is calculated from the first day of the last menstrual period (LMP), which is typically about 2 weeks before conception.

3. Importance of Due Date Calculation

Details: Accurate due date estimation is crucial for proper prenatal care, monitoring fetal development, and planning for delivery. It helps healthcare providers schedule important tests and assessments at the appropriate times during pregnancy.

4. Using the Calculator

Tips: Enter the known or estimated conception date. The calculator will provide the estimated due date and current gestational age if the conception date is in the past.

5. Frequently Asked Questions (FAQ)

Q1: How accurate is this calculation?
A: While 266 days is the average, normal pregnancies can vary by ±2 weeks. Only about 5% of women deliver on their exact due date.

Q2: What if I know my LMP but not conception date?
A: The standard Naegele's rule adds 280 days (40 weeks) to the first day of your last menstrual period (LMP).

Q3: Does this account for leap years?
A: Yes, the calculator automatically accounts for leap years in the date calculation.

Q4: Why 266 days instead of 280?
A: 280 days (40 weeks) is counted from LMP, while 266 days (38 weeks) is from conception, which typically occurs about 2 weeks after LMP.

Q5: How does ultrasound dating compare?
A: Early ultrasound measurements (especially first trimester) can provide even more accurate dating than LMP or conception date estimates.