There is a LOT of information here on the Forum about BCG....In fact, I would bet that it is our "favorite" topic! For a start, go to the thread "Non-invasive...." You will find, at the top, several threads that cover this topic extensively which we have saved for people such as you, new to the topic, and wanting information. You can also use the "Search Forum" funtion at the top of this page.
If you have any questions after checking these out, ask away and we will try to answer them.
Sara Anne
