Have any women treated their PCOS with diet?

Yes. I have PCOS and found out after hubby and I had tried to conceive for 3 years. I ended up taking a dose of clomid and it was successful that. After that my monthly cycles did not return and I was told there was really no way of becoming preggy since I do not ovulate. For almost FOUR years after having the other child I participated in a fitness challenge at my local gym. Going earned points as did weight loss. I went to the gym every day for an hour for six weeks. While doing this I did the South Beach Diet religiously. I lost 15 lbs in those 6 weeks! A few weeks after the end of the challenge I started to feel sick. I was better by late afternoon and hubby finally said I should take a preggy test. WHAT!?!? I thought. But alas, here I am, 30 weeks preggy with our little surprise. Turns out that that diet and exercise caused me to ovulate. So I can say with certainty that the South Beach Diet combined with exercise straightened me out. I have found the South Beach Diet to make me feel a LOT better. Since PCOS is basically a pre-diabetic state, high carb diets always made me feel groggy and sluggish. I did not realize how much they did until I felt the effects of the diet. I would highly suggest your wife try this out. It's hard so she'll need your support. Perhaps you can do it with her. PCOS also causes intense carb cravings so getting through Phase 1 can be a challenge w/o willpower! Good luck to you and to her, PCOS can really cause havoc to a body and she will love your support as she tries to curb her symptoms!