my sister has PCOS and breast fed all 3 of her children. I dont know details except only the last one needed suplementation due to nutritional concerns and that it took her first one a week or 2 to get the hang of nursing.
My BFF just had a baby and after about a week had to give up on trying because even with pumping, she was getting maybe 3 oz a day. However- her lactation consultation said it may be actualy be problems from scar tissue from 2 open heart surgeries about 10 and 12 years ago (late teens/early 20s). She is not officialy dxed with PCOS, but she has a lot of the symtoms.
I also have PCOS and plan on trying ot BF, but keeping a formula plan on the table because I had radical breast reduction done 17 years ago (I was 16, and wore a 32G- it was causing malformation of my shoulders, ribs, and back) so I dont know if I will be able to anyway.