method
Conception Date Calculator
Calculate when conception likely occurred based on your due date or last period.
Gestational age calculations follow ACOG Committee Opinion on methods for estimating the due date, cross-referenced with NHS and AAFP clinical guidanceReview is overdue.Reviewed: March 2025Full Methodology
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Due Date from LMP
Calculate the due date using the first day of the last menstrual period (10 weeks ago).
Key values: LMP method · 28-day cycle · Singleton
First Trimester Check
A pregnancy at approximately 8 weeks from conception date.
Key values: Conception method · 8 weeks ago · First trimester
Ultrasound Dating
Calculate timeline from an ultrasound performed at 12 weeks, 3 days.
Key values: Ultrasound method · 12w 3d at scan · 4 weeks ago
IVF Transfer Timeline
Estimate due date from a day-5 embryo transfer completed 14 days ago.
Key values: IVF method · Day-5 transfer · High confidence dating
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