Since many women who are assisted reproduction pregnant are confused about their last menstrual period and maternity period, the calculation of last menstrual period and maternity period for IUI, IVF day 3 transfer and blastocyst transfer are published as follows The calculation methods of last menstruation and maternity period for artificial insemination, IVF day 3 transfer and blastocyst transfer are announced and examples are as follows: 1. For example, if a woman has artificial insemination on October 20, her last menstrual date is October 6. (1) If the embryo is transferred on the 3rd day, the last menstrual date is the date of transfer minus 17 days. For example, if a woman’s transfer date is October 20, her last menstrual period will be October 3. (2) If day 5 and day 6 blastocysts are transferred, the last menstrual date is the transfer date minus 19 days. For example, if the transfer date is October 20, the last menstrual period will be October 1. Calculation of the expected date of delivery: All maternity dates are calculated by adding 9 to the month of the last menstrual period and adding 7 to the date of the last menstrual period. For example, a woman’s last menstrual period is February 3, 2015, which means that the maternity date is approximately November 10, 2015.