What does it mean spotting between your period?

Spotting - also known as "breakthru bleeding" is either having a "mini period" between the 27-28 some odd days between ones "normal" period or (as the Word implies). Times where there are spots of blood between the cycle. This can last a day or a week.

There are times it can act as a normal period - the term is broad based and depends on what ones physician has indicated for the female experiencing it.