Time pregnant is counted from the first day of your last menstrual period.

All four fields in the due date calculator (estimated due date, weeks pregnant, last menstrual period, and date of conception) are connected and take into account 38 weeks of gestation and approximately 2 weeks from your last period until ovulation. If you enter your date of conception, Ovia will add two weeks to account for the time between your last menstrual period and date of conception.

Please check out out our article on calculating time pregnant: