Implantation Bleeding

Implantation bleeding is light bleeding that may be experienced at the onset of pregnancy.  This bleeding is usually lighter, shorter or more spotty that a regular menstrual cycle.  Implantation bleeding and small cramping often lead women to believe they are experiencing a pending period.

What causes implantation bleeding?

Implantation bleeding may occur when the fertilized embryo implants in the uterine wall following conception.  The penetration of the fertilized egg into wall may trigger traces of blood which is usually lighter and shorter than a regular period.

When does implantation bleeding occur?

Implantation bleeding first occurs sometime between four to 10 days after conception; it is usually closer to six days.  It is possible that you may experience small traces of implantation bleeding for up to 29 to 35 days after your last menstrual period (LMP).

How frequently do they occur?

Because implantation bleeding may be so light or short and that some women will actually miss it; it is hard to know an accurate percentage of women that experience implantation bleeding. 


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