Epistemis

Gestational Age and Naegele's Rule

Calculates the Probable Date of Delivery (PPD) based on the date of the last period (LMP) using the classic Naegele formula:

Required inputs

The inputs this calculator asks for inside the app.
VariableExample value
First Day of Last Period (FUR)2025-01-15
Do you have a First Trimester Ultrasound?
Date of Ultrasound2025-03-01
Cephalo-Caudal Length (CRL) (mm)45

Run the calculation in the app

This page explains the score but does not run it. In Epistemis, the calculator validates units, flags values outside physiological ranges, and provides the interpretation that a number alone cannot convey.

Epistemis is educational review material. It is not a medical device, does not diagnose or prescribe treatment, and does not replace formal medical training, current clinical guidelines, or professional clinical judgment.

Specialty
Gynecology and Obstetrics
Area
Specialties
Variables
4
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