Any hormonal issues, birth control, menopause, anything like that?

Have you tried using store-bought lubricant (even if it seems like you don't have to)? That might be worth a shot.

And also, it would be helpful to know where the pain is. If it's more external (the outer vagina or vulva) it's probably due to friction, but pain in her cervix (which would be deeper or feel like sharp abdominal cramps) would more likely be due to irritation/bumping up against her cervix during sex (deep penetration usually). Also, does it happen more or less at different times during her cycle?

we've tried different lubricants... she has been on birth control for well over a year without issue... and she is 21... so no menopause...

this has been going on for a while... it didnt start happening until once about a year ago... we had purchased condoms w/ spermicide lubricant by accident and decided to use them anyways... it seemed to bother her quite a bit after the fact... in consistant pain... and ever since then... we've been having this problem.... talked to her doctor and he found nothing but a little swelling

it doesnt seem to matter what time of the month it is... if we wait a week or so... she will be fine... we can do what ever we want but if we try to do it again shortly there after... the pain is back.

the pain seems to be as soon as i enter her (sorry for lack of medical terminology)

its pretty instant... but seems to lighten the deeper in i am... so i would say right at the entrance....

-EDIT-
she describes the pain like a sunburn that someone is touching if that helps at all...

Thanks

Yeah, that sounds like friction pain to me, as I get the same thing. It doesn't hurt once the penis is inside. Have you taken any long breaks form sex since the spermicide condoms? She may have been chemically burned by them (not as serious as it sounds) and has not been able to heal since then.

Yeah, spermicide did that to me. Also, birth control can make you dry in general. She isn't on the ring, is she? Anyway... I'd say try using lubricants (and reapplying often, it does dry up) and really over-do it. If that works, you know your problem. If that doesn't help, she might want to push the issue with a doc or change birth control.

we took several long breaks... one of which was nearly 3 months... and the others around a month at a time without any sexual contact...

any ideas?

She's not on the ring, is she?

Otherwise, just what I said. Use a ton of lube, re-applying, and see if it works. If it doesn't help, she should probably see her doctor. There are some conditions that have painful sex as a symptom. If the doctor isn't finding anything wrong, push the issue, and perhaps a change in birth control.