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Understanding Conception Date Estimation
Formula
Conception typically occurs about 266 days (38 weeks) before the due date, or approximately 14 days after the last menstrual period for a 28-day cycle. The conception date calculator estimates this by working backward from the due date or birth date.
The actual day of conception may vary by a few days from the estimate since sperm can survive up to 5 days in the reproductive tract and the exact ovulation date varies between cycles.
Common use cases:
- Estimating conception timing
- Paternity questions
- Understanding pregnancy timeline
Frequently Asked Questions
Dr. David Park
Applied Mathematician, PhD Mathematics
David holds a PhD in Applied Mathematics from MIT. He has published research on numerical methods and computational algorithms used in engineering and scientific calculators.
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