The best way to determine your conception date is with a pregnancy confirmation ultrasound. Pregnancy ultrasounds look directly at the development of your growing baby to determine its age and when you likely conceived.

Can you tell when you conceive?

"You can take a home pregnancy test," says Dr. Hou. But since implantation happens one or two weeks after ovulation, it may be too early to get an accurate reading. It's better to wait about a week after implantation when levels of the hCG will be high enough to detect.

How do you calculate date of conception?

Typically women ovulate about two weeks after their menstrual cycle starts, so the best way to estimate your due date is to count 40 weeks, or 280 days, from the first day of your last menstrual period. Another way to do it is to subtract three months from the first day of your last period and add seven days.