1. What is the Pregnancy Due Date Calculator?

The Pregnancy Due Date Calculator estimates the expected date of delivery (EDD) based on the first day of the last menstrual period (LMP) using the standard Naegele's rule (280 days or 40 weeks from LMP).

2. How Does the Calculator Work?

The calculator uses the following formula:

Where:

• LMP — First day of last menstrual period
• 280 days — Standard length of pregnancy (40 weeks)

Explanation: This calculation assumes a regular 28-day menstrual cycle with ovulation occurring on day 14.

3. Importance of Due Date Calculation

Details: Accurate due date estimation is crucial for proper prenatal care, monitoring fetal development, and planning for delivery.

4. Using the Calculator

Tips: Enter the first day of your last menstrual period in the format YYYY-MM-DD. The calculator will add 280 days (40 weeks) to this date.

5. Frequently Asked Questions (FAQ)

Q1: How accurate is this due date calculation?
A: Only about 5% of women deliver on their exact due date. Most deliver within 2 weeks before or after.

Q2: What if my cycle isn't 28 days?
A: The calculation may need adjustment. Consult your healthcare provider for a more accurate estimate.

Q3: Can ultrasound change my due date?
A: Yes, early ultrasound measurements (especially first trimester) may lead to adjustment of the due date.

Q4: What's the difference between gestational age and fetal age?
A: Gestational age is measured from LMP, while fetal age is from conception (typically 2 weeks less).

Q5: When should I contact my doctor about my due date?
A: If you have irregular cycles, don't know your LMP, or if your ultrasound due date differs significantly from LMP calculation.