I experienced a series of miscarriages this year.  After completing a variety of tests and procedures, it was discovered that scar tissue, likely from a d&c after the first miscarriage, was likely preventing the additional pregnancies to progress.  The scar tissue blocked part of my uterus, creating a smaller cavity and limited blood supply to the embryos.  I just had surgery - a hysteroscopy- using microscopic scissors to remove scar tissue.  Now I have a small balloon in my uterus - likely for one week- to prevent additional scar tissue from emerging and to prevent the uterus from adhering to itself.  It's pretty uncomfortable, but not as horrific as I anticipated.  We're hopin to proceed with invitro in a couple of months.