Question 1

Is the conception date exact?

Accepted Answer

It is an estimate. Sperm can survive days; ovulation timing varies.

Question 2

Why 266 vs 280 days?

Accepted Answer

280 dates from LMP; ~266 approximates fertilization-to-due in a 40-week LMP framework.

Question 3

Medical record conflicts?

Accepted Answer

Trust your provider’s dating, especially after early ultrasound.

Conception Calculator

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