*butts in* (and that is such a poor choice of words considering the topic ^^;;)

speaking from my (limited) personal experience they do not poke you in there unless they can't get an image off the regular ultrasound wand (the one you see on TV/movies/etc when pregnant ladies get ultrasounds). so unless you're over-weight(like me >.>) or something, you should be good. if you do need a internal exam, tell the doctor doing your exam and they should walk you through it.

hope this helps ^^;

*leaves her 2 cents and runs*