Implantation bleeding is defined as a small amount of light spotting or bleeding. It typically occurs about 10 to 14 days after conception. Implantation bleeding is common, and it usually isn't a sign of a problem.

Implantation bleeding is thought to happen when the fertilized egg attaches to the lining of the uterus. Implantation bleeding usually occurs around the time you would expect to have a menstrual period. However, implantation bleeding is lighter than menstrual bleeding.

Some people don't experience implantation bleeding and others don't notice it. Sometimes, implantation bleeding is mistaken for a light period. If this happens, you might not realize that you're pregnant. This can lead to mistakes when determining a baby's due date. A fetal ultrasound — typically done during the first trimester of pregnancy — can help accurately determine the baby's due date.

Implantation bleeding is light, stops on its own and doesn't require treatment. If you're concerned about any vaginal bleeding during pregnancy, contact your health care provider.