I know I am.
There is no physical reason that I know of why I wouldn't be able to. Periods have always been totally normal and regular, I haven't had any major medical treatments that might make it unlikely. But I still worry that I might not be able to have them, as I won't know for sure until I start ttc.
Also, I have a coil in and the other day there was something on the radio about how they didn't used to put coils in women who hadn't had children, in case it damaged them or something and made them infertile. I have never had an infection with mine, but still worry about this!
I think it's just because I really want them, and I am a natural pessimist! Can't imagine life being any good without them.