When to stop birth control

I have been on the pill for 15 years (I'm 33 now) & never experienced significant side effects until the last year or so.  I am getting migraines that seem to be hormonal as they tend to start during PMS.  I'm just getting over a 3 day migraine now that made me so nauseous I threw up.  My periods have also become irregular - spotting between periods & some missed periods.  My doctor said the irregularities don't mean anything unless they continue when I go off the pill.  I'm planning on going off the pill just before our December wedding as we want to start TTC right away once we're married.  I guess I'm wondering if I should tough it out until then, or if I should go off the pill sooner to make sure nothing is wrong and get back into a normal cycle for a while before TTC?  What have been your experiences with going off the pill & getting pregnant after a long time on birth control?