Does Implantation Bleeding Always Happen?

    Implantation bleeding is small spotting that can happen at the time of implantation, the attachement of the fertilized egg to the uterine wall.

    Some women report spotting around the time the egg implants into the uterus. There are few data available on how often this happens. But it's likely that most women who become pregnant do not experience implantation bleeding, and many women who are not pregnant experience some spotting.