text: my girl friend has been having problems with her period. its either really late or it will skip intire months. please help figure out what is wrong! wow, it could be all manner of things. birth control pills/ patches can cause her periods to be irregular. pcos (poly cystic ovarian syndrome)or an std. have her see a gynocologist asap. please don't wait on this. could be a sign of a serious infection that could possibly interfere with fertility. i don't mean to scare you, but i have to impress how important it is that she see a doctor