Right before or about the same time you would normally expect your menstrual period, you may experience a small amount of spotting and occasionally some mild cramping. This sometimes happens 3-12 days after conception, when your newly-fertilized egg implants itself into the lining of your uterus (or the “endometrium”).
Implantation bleeding is lighter than a regular menstrual period and usually pink or brownish in color. Implantation bleeding may confuse you, since it’s not always easy to tell whether you’re experiencing break-through bleeding between periods, a lighter-than-normal period or in fact, spotting from implantation.
The majority of women don’t experience spotting at the time of implantation, but for others, it can be one of the earliest symptoms of pregnancy.