Leg Squeezing = ConeHead???

I'm a leg squeezer. Pretty much been doing it since I can remember... I don't get off by fingers, or toys, or humping things... but by squeezing my legs together for a few minutes. I know a lot of women do it, although it's not really talked about and I have not found very much information on the subject.

Does anyone else masturbate this way? and does it cause any harm to your baby? I don't know, subconsciously I feel like I am going to squeeze and give my baby a cone head! Or not be able to give birth vaginally... (ok, I know that one makes no sense but it's truly something I worry about!)