A lot might depend, for you, on when the group was formed and if you are a new member among those who have already been meeting for a time or if the group is brand new and everyone is new. Too, your leader(s) are very important, how well they lead and how comfortable and safe they make you feel while sharing. Age of members might be significant and other experiences; if you are young and single and there are several older, married women with kids, that could make a difference.

Think of some easy way to introduce yourself maybe. Bare facts like, "I'm trdleblue, 24, and was sexually abused by a family friend when I was 8" will go a long way for the first couple sessions while you are listening and coming to better understand the dynamics of your particular group and its members. Start with obvious, factual statements (you are in a csa group so everyone has been affected by csa) and maybe think how to gradually expand on them when you see a good place; if someone talks about how they were abused by their uncle, for example, and you were abused by your cousin and wonder about your uncle, you might ask some questions and give some information about yourself, relating to the other person and thus get a little closer to your feelings, based on how brave the other person is (or you wish you or they were) in sharing there's, etc.

I went rappelling down cliffs once in college because another girl I admired was brave enough to be first of the girls and I didn't want to be thought too scared :-) I got stuck on a ledge (the site was not picked well, we didn't really have but half an expert with us) and it turned out to be one of my best experiences ever, talking myself off that ledge and down (it was too small for a helicopter to rescue me and I couldn't climb back up, something had to give so I went for it and continued down :-) and I found group therapy to be a little like that, challenging yourself in light of other people's bravery or your wish to comfort another by letting them know you yourself have had similar experiences and they are not in it alone, etc.