1. What Is Pregnancy Due Date Calculation?

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

2. How Does The Calculator Work?

The calculator uses the standard pregnancy due date formula:

Where:

• \( EDD \) — Estimated Due Date (date)
• \( LMP \) — Last Menstrual Period (date)
• \( 280 \text{ days} \) — Standard pregnancy duration (40 weeks)

Explanation: This calculation assumes a regular 28-day menstrual cycle and ovulation occurring on day 14. The 280 days represents 40 weeks of gestation from 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 screenings, 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. Ensure the date is accurate as this forms the basis for all subsequent pregnancy dating. The calculator will provide both the estimated due date and current pregnancy week.

5. Frequently Asked Questions (FAQ)

Q1: How accurate is the due date calculation?
A: The calculation provides an estimate - 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 my menstrual cycle is irregular?
A: For women with irregular cycles, an early ultrasound (usually between 8-12 weeks) provides more accurate dating than LMP-based calculation.

Q3: 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, and it provides a standardized method for healthcare providers.

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 are the trimesters of pregnancy?
A: Pregnancy is divided into three trimesters: First trimester (weeks 1-13), Second trimester (weeks 14-27), and Third trimester (weeks 28-40+).