Online Pregnancy Conception Calculator
Pregnancy Conception Calculator
This calculator helps estimate the conception date based on due date, last menstrual period (LMP), or current pregnancy information.
Conception Date Results
Fertility Window
Based on your cycle information, here's when conception was most likely:
Pregnancy Timeline
Key Facts About Conception
- Conception typically occurs within 24 hours of ovulation
- Sperm can survive in the female reproductive tract for up to 5 days
- The fertile window includes the 5 days before ovulation and the day of ovulation itself
- Implantation usually occurs 6-12 days after conception
- Pregnancy tests can typically detect pregnancy 10-14 days after conception
Understanding Conception Dates
The conception date is the day when sperm fertilizes the egg. This calculator estimates when conception most likely occurred based on different pregnancy milestones.
Conception vs. Last Menstrual Period
Conception typically occurs about 2 weeks after the first day of your last menstrual period. This is because ovulation (when the egg is released) usually happens around day 14 of a 28-day cycle.
Conception from Due Date
Since pregnancy lasts about 40 weeks from LMP (or 38 weeks from conception), you can estimate conception by subtracting 38 weeks from your due date.
Ultrasound Measurements
Early ultrasound measurements like Crown-Rump Length (CRL) can provide accurate estimates of gestational age, which can then be used to calculate conception date.
Factors Affecting Conception Timing
Several factors can influence when conception occurs, including cycle length, luteal phase length, and the exact timing of ovulation. This calculator accounts for these variables to provide the most accurate estimate possible.