Pregnancy due date

Calculation based on:
First day of last menstrual period
Conception date
Date of 3-day embryo transfer
Date of 5-day embryo transfer


Estimated due date:

Computational notes

Conception date can be date of ovulation, egg retrieval, or insemination.

The pregnancy due date is estimated by adding 280 days (9 months and 7 days) to the first day of the last menstrual period (LMP).

When the date of conception is known precisely, such as with in vitro fertilization, the estimated pregnancy due date is calculated by adding 266 days to the date of conception.

Please remember that your due date is only an estimate. Every pregnancy is unique and your baby will come when it's ready. Be sure to talk to your health care provider about your due date.

Disclaimer: The authors make no claims of the accuracy of the information contained on this web page. Your reliance upon information and content obtained at or through this website is solely at your own risk. All calculations must be confirmed before use. MedCalc Software shall not be liable for any special, consequential, or exemplary damages resulting in whole or part from any user's use of or reliance upon this material.

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