Hey @viking1, I was told by my surgeon not to wear underwires as I had mastectomy with implant and she told me it can lead to encapsulation issues (where tissue grows around implant and causes pain and problems) another very knowledgeable lady (bows to @primek) has cleared this up for me by advising it is in fact due to bacteria. Unfortunately I had already given my gorgeous underwires to my sister. If you are worried about the underwires you could always be a smarty like Jane @Hopes_and_Dreams who removed the underwire from her mastectomy side - too clever !!! Xx