for those of you with long/irregular cycles, how long does your DR let you go without a period before they induce it?

i'm on day 71 of this cycle (which is totally awesome when your TTC, ugh) and have an appt on monday. she usually lets me go 80 before she says i have to induce AF. i start acupuncture a week from tomorrow, so maybe they can get it started without me having to take anything. i did try vitamin C mega dosing, but only gave myself hot flashes and a nasty headache =(