Pregnancy Timeline: Determining Conception Date Based on Ultrasound

No, it is not possible that you conceived on February 29, 2008, if an ultrasound determined that you are 8 weeks and 1 day on April 23, 2008. Pregnancy is typically calculated from the first day of your last menstrual period, and 8 weeks and 1 day of pregnancy would be closer to 10 weeks from conception. Since February 29 is not a leap year, it would be impossible to have conceived on that day in 2008.