Hi Pandaeyes
Re your comments:-
"To be honest though, my pcos must be quite mild as other than the cysts and slightly long cycles, I have no symptoms".
PCOS is PCOS. It is though a very individualistic disorder and thus it does affect women with it very differently. My only symptoms were irregular periods and a couple of stray hairs in the nipple area. Came as something as a shock to me also, I had never heard of PCOS till diagnosis.
"I DO ovulate every month. If I chart, the chart is very normal looking (definitely no rocky mountains) and I get a +opk on the day of O etc".
Again (and I am sorry to say this) I would not assume you are actually ovulating solely on the basis of temp charts (you can have a temp rise in the second half of your cycle when an egg has not been shed) and opk's. Blood tests are the only accurate indicator here, if blood tests are showing ovulation then fabulous. OPK's measure the amount of LH hormone; with PCOS many people produce an excess of such a hormone and the kit will thus read that. OPK's are a waste of money if PCOS is an issue; spend that cash on something else instead for your good self!!!.
"I guess I'm struggling to accept I have pcos but I have not conceived after 4 cycles so I am resigned to starting the horrid sounding metformin when af comes!".
I think you are struggling with this PCOS issue like many women and I can empathise because I felt the same on diagnosis. You may not need metformin at all, it is not for all PCOSers to take. It is usually for women who show signs of insulin resistance (not all women with PCOS are IR). There are other treatments out there for PCOS (I had ovarian diathermy surgery) but as previously mentioned no one therapy or treatment will completely eradicate PCOS as the cystic follicles do return over time.
Verity is helpful and would suggest you look at their website for more information (infact I would say that to any PCOSer)
www.verity-pcos.org.uk
I would seriously consider asking your GP now for a referral to a gynae.