1. What is the Due Date Calculator?

The Due Date Calculator estimates the expected delivery date based on the last menstrual period using the standard 280-day pregnancy duration. This calculation is commonly used in perinatal services for pregnancy dating and monitoring.

2. How Does the Calculator Work?

The calculator uses the standard obstetric formula:

Where:

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

Explanation: This calculation follows Naegele's rule, which adds 280 days (40 weeks) to the first day of the last menstrual period to estimate the due date.

3. Importance of EDD Calculation

Details: Accurate due date estimation is crucial for proper prenatal care, monitoring fetal development, scheduling important tests, and preparing for delivery. It helps healthcare providers track pregnancy progress and identify 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 for the most reliable due date estimation. The calculator will automatically compute your estimated due date.

5. Frequently Asked Questions (FAQ)

Q1: How accurate is the 280-day calculation?
A: While 280 days is the standard, only about 5% of women deliver exactly on their due date. Most deliveries occur within two weeks before or after the estimated date.

Q2: What if I have irregular periods?
A: For women with irregular cycles, an early ultrasound dating is more accurate than LMP-based calculation for determining the due date.

Q3: Can the due date change during pregnancy?
A: Yes, healthcare providers may adjust the due date based on early ultrasound measurements, which are most accurate in the first trimester.

Q4: What is gestational age vs fetal age?
A: Gestational age is calculated from LMP (about 2 weeks longer than fetal age), while fetal age starts from conception. Medical professionals typically use gestational age.

Q5: Are there other methods to calculate due date?
A: Yes, other methods include ultrasound measurements, conception date calculation, and IVF transfer date calculation for assisted pregnancies.