Gynecologists?

I'm 16 and I'm sexually active, I want to start seeing a gynecologist but would I have to have a parents consent since they are looking all up in there? My mom doesn't know and I know people are going to say "you should tell your mom blah blah" but my sister knows everything that goes on with me including my partners and when, but I really want to know if I need my mom to go with me or if I need a parents consent because I really don't want her to find out