Hi, I'm coming in to this late & haven't read the whole thread, but thought I'd just add my experience.
I have PCOS & had been on & off dianette for a few years before TTC. In the off times (stops working for me after about 6 months & my normal horrific periods reassert themselves), I did natural family planning, which is kind of a rational scientific version of the rhythm method, charting temps but also mucus & cervical position. I realised I was only ovulating every other month, plus my cycle got really erratic, particularly when I was stressed.
Anyway, 18 months or so ago, dianette stopped working again and dp & I figured we'd try nothing & see what happened for a couple of years, by which time we'd have lots of charts showing my mayhem cycle & could go through worst case IVF etc but still not be totally ancient. 3 months later, I was up the duff, and now have beautiful 7 month old.
There was one thing that did seem to change my cycle & make it more regular, it's weird, and I'm totally not superstitious, but it was leaving my curtains open to let the full moon in just at full moon, or sleeping with a nightlight on if it was cloudy. Whenever I remembered, my cycle was a neat 28 days, and the month I got pregnant our bedroom curtain rod collapsed & we couldn't be arsed to put it back up!
I read something about it, a book called 'The Wise Wound', a bit old-school periods are great (not mine!) stuff, but had an interesting bit about research into sea birds and how the base brain that controls basic functions like reproduction is the really old bit of brains that even birds have, and kind of works like an eye and responds to direct light on it. There was something about an experiment painting black dots on cormorants' heads, that made them forget to mate, or migrate or something. Anyway, worth a go, but mostly relax and enjoy the sex , once you've got a bub it'll become a distant memory!