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OB-Gyn — EDD & Gestational Age

Estimate Expected Date of Delivery (Naegele's rule) and current Gestational Age from the patient's last menstrual period (LMP).

EDD = LMP + 7 days − 3 months + 1 year · GA = today − LMP

Last Menstrual Period (LMP)

First day of the last normal menstrual period.

Today: 10 June 2026

Naegele's rule assumes a regular 28-day cycle. For irregular cycles or after IVF, prefer ultrasound dating in the first trimester (CRL).

Gestational Age

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Estimated Date of Delivery

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Trimester

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Days remaining

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Select an LMP date.