According to the Iron Overload Diseases Association, an average human body loses only about 1 milligram of iron a day, through hair, fingernails, skin cells, and other organic waste. It's about 1.5 milligrams for women of reproductive age. We get iron in our diets and it is not excreted. Therefore, it's hard to produce a net loss of iron without phlebotomy or chelation.
No individual is "average" so it's worth knowing your serum ferritin level. Even if it does not drop while you are transfusion independent, I'm sure you're glad not to have it rise.
For more information, see
A New Perspective on Iron Deficiency, and of course talk to your own doctor.