Otosclerosis is a hereditary condition in which hearing loss occurs slowly, over time and involves the stapes bone of the middle ear.  It is common in women and is aggravated or made worse with pregnancy.  If mild, hearing aids can be helpful.  For more severe cases, surgery, stapedotomy, can be done and is performed using a laser.  The affected middle ear bone, the stapes, is replaced with a prosthesis.