1. What Is The Pregnancy Calculator MSD?

The Pregnancy Calculator MSD estimates the due date based on the last menstrual period using the standard 280-day pregnancy duration. This method follows the Naegele's rule for pregnancy dating.

2. How Does The Calculator Work?

The calculator uses the standard pregnancy calculation formula:

Where:

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

Explanation: This calculation assumes a regular 28-day menstrual cycle and 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 prenatal care planning, monitoring fetal development, scheduling important tests, and preparing for delivery.

4. Using The Calculator

Tips: Enter the first day of your last menstrual period in the date field. The calculator will provide your estimated due date and current gestational age.

5. Frequently Asked Questions (FAQ)

Q1: How Accurate Is This Calculation?
A: This method is accurate for women with regular 28-day cycles. For irregular cycles, ultrasound dating may be more precise.

Q2: What If My Cycle Is Longer Than 28 Days?
A: For longer cycles, add the number of extra days to the calculated due date. For example, if your cycle is 35 days, add 7 days to the EDD.

Q3: When Should I Confirm With Ultrasound?
A: Early ultrasound (8-12 weeks) provides the most accurate dating and is recommended to confirm the due date.

Q4: What Percentage Of Babies Are Born On Their Due Date?
A: Only about 5% of babies are born exactly on their due date. Most are born within two weeks before or after.

Q5: Can This Calculator Be Used For IVF Pregnancies?
A: For IVF pregnancies, use the embryo transfer date plus 266 days (or 38 weeks) for more accurate dating.