I have friends and family with PCOS. My friend has stayed stable around 300 lbs, whereas my family member has only continued to grow past that weight since we were kids. In both cases, they have issues with food. My friend used to binge eat, and my cousin has absolute dogshit nutritional sense, despite being a vegetarian.
The disease makes it wicked easy to gain weight, and incredibly hard to lose it. Fat is stored primarily in the belly, and because it causes testosterone production, some people get body and facial hair. Exercise only stimulates the testosterone production too. And yes, periods are miserable and fertility is questionable.