PCOS and Weight The relationship between obesity and polycystic ovary syndrome may be exaggerated. Study finds women with PCOS had about the same obesity rates as those who didn't have PCOS. Dr. Azziz said. "A lot of patients believe PCOS leads to obesity and we really don't have strong data to support that. In fact, our evidence suggests that is not the case. Growing evidence also suggests that -- regardless of how much they have -- the fat in women with PCOS behaves differently."