When your doctor figures your due date, he or she will work from your last date of menstruation, so technically your pregnancy “begins” about two weeks before your egg was fertilized. See what else is happening during weeks 1-2. © Medical-Artist.com
Even though you may not feel pregnant yet, your body is already going through huge transformations—long before your baby has even began developing.
Pregnancy technically begins at implantation—when your fertilized egg implants into the wall of your uterus—which is usually about five days after fertilization.
However, the first two weeks are included in your overall pregnancy timetable, which is a total of 40 weeks—this includes fertilization. If you’re looking to calculate your due date, add 280 days to the date of when your last period began.
Read more about weeks 1-2.
Reviewed by Dr. Jen Lincoln, November 2018