Hi sandilu, I have such a clip in my right breast. As "J" mentioned, it's placed at the location where the biopsy was performed and serves as a reference marker for future diagnostic purposes. So, it'll always show up on your mammograms. The needle biopsy process can be rather time consuming; but it's virtually painless. The position that you'll have to lie down in will probably be the most uncomfortable part of the procedure. A local anesthetic is used and, you'll feel a bit of pressure from the needle probe. The healing is quick and the scarring is minimal. I have a small puncture scar that is barely noticeable. Best wishes and good luck.
The clips are made of titanium. They are placed to mark the site of the biopsy. It helps guide clinicians to the site of interest. This can assist in both diagnosis and treatment.
This subject came up again recently for me.
Previously there was talk of needing a clip after having a stereotactic breast biopsy. I didn't consent to one and the doctor didn't think one was necessary. However, after several surgeries and now a need for radiation therapy I have been told my whole breast needs the radiation and not just a single isolated area because the location was not marked.
You may find some information if you look up stereotactic breast biopsy or maybe even titanium clips used in breast biopsies, etc.
There have been some discussions about these clips on this forum so you may also like to search the archives.
J