Women can estimate the when they got pregnant, also known as the date of conception, based on their last menstrual period, according to the American Pregnancy Association. Some women know the exact date of conception in their pregnancies because they have had certain medical procedures or have infrequent sexual encounters.Continue Reading
For women who know the first day of their last menstrual period before they got pregnant, they can estimate when they got pregnant because conception usually occurs 10 to 11 days after the first day of a menstrual period, reports the American Pregnancy Association. For this reason, it is helpful for couples trying to get pregnant to keep track of menstruation and ovulation cycles and sexual activity with a calendar. Some pregnant women do not know the first day of their last menstrual period, so determining the date of conception is based on their best guess.
For pregnant women who have had infrequent sexual encounters, they may know the exact date of conception without calculating it based on their last menstrual cycle. Women who undergo artificial insemination or in vitro fertilization will typically know the date of conception because it is the date that procedure took place explains the American Pregnancy Association. BabyCenter has a useful tool on its website for pregnant women to help them calculate their due date based on the first day of their last menstrual period.Learn more about Pain & Symptoms