I also have PCOS (only diagnosed 3 months or so) & have been low carbing now for about 2 months - although not Atkins but much more gently - following Dr Schartzbien's Program of Wellness. So Although I have lost 10kg it has not been at a dramatic rate.
However my Gynecologist said that how much you were losing was not the key thing - it was the direction that was important. She said that the latest research was showing that even loses per week as little as 0.5g would greatly increase fertillity....Although i a not pregnant yet this theory seems to be working with me as I had my first 'regular' cycle ever last month - which feels like a great achievement

Good luck...