1. What is Pregnancy Due Date Calculation?

The pregnancy due date calculation estimates the expected date of delivery based on the first day of the last menstrual period. This method, known as Naegele's Rule, adds 280 days (40 weeks) to the first day of the last menstrual period to determine the estimated due date.

2. How Does the Calculator Work?

The calculator uses the standard pregnancy due date formula:

Where:

• \( EDD \) — Estimated Due Date
• \( LMP \) — First day of Last Menstrual Period
• \( 280 \) — Standard pregnancy duration in days (40 weeks)

Explanation: This calculation assumes a regular 28-day menstrual cycle and that conception occurred approximately 14 days after the first day of the last menstrual period.

3. Importance of Due Date Calculation

Details: Accurate due date calculation is essential for proper prenatal care, monitoring fetal development, scheduling important tests, and preparing for delivery. It helps healthcare providers track pregnancy progress and identify any potential complications.

4. Using the Calculator

Tips: Enter the first day of your last menstrual period in the date field. The calculator will automatically compute your estimated due date by adding 280 days (40 weeks) to the entered date.

5. Frequently Asked Questions (FAQ)

Q1: How accurate is this due date calculation?
A: This method provides an estimate. Only about 5% of women deliver exactly on their due date, with most delivering within two weeks before or after the estimated date.

Q2: What if my menstrual cycle is longer or shorter than 28 days?
A: For women with irregular cycles, an ultrasound measurement in the first trimester often provides a more accurate due date estimate.

Q3: Why is pregnancy calculated from the last menstrual period instead of conception?
A: Most women can accurately recall their last menstrual period date, while conception date is often unknown. This provides a consistent starting point for calculation.

Q4: Can the due date change during pregnancy?
A: Yes, healthcare providers may adjust the due date based on early ultrasound measurements, especially if there's a significant difference from the LMP-based calculation.

Q5: What is considered full-term pregnancy?
A: A pregnancy is considered full-term between 39 weeks 0 days and 40 weeks 6 days. Early term is 37 weeks 0 days through 38 weeks 6 days.