How is conception estimated from due date?

Pregnancy is about 266 days from conception to due date. So conception ≈ due date minus 266 days.

How from last period?

Ovulation/conception is typically about 14 days after the first day of your last menstrual period (LMP).

Estimate conception date from due date (≈266 days before) or from last menstrual period (LMP) date (≈14 days after LMP).

Method

From due dateFrom last period (LMP)

Due date

How is conception estimated from due date?: Pregnancy is about 266 days from conception to due date. So conception ≈ due date minus 266 days.
How from last period?: Ovulation/conception is typically about 14 days after the first day of your last menstrual period (LMP).

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