In my case, as far as I remember, the docs never directly related thyroid issues with PCOS, but thyroid issues to hypothyreosis; hypothyreosis to a slow metabolism, a slow metaboism to weight
gain to obesity
, obesity to pre-diabetic issues and PCOS.
The thyroid issues have been an incidential finding; I was diagnosed with Hashimoto and was put on L-Thyroxin 50µ. That was 10 years ago; I weighted 50kg, had a small thyroid and no PCOS.