Hi. Thanks for your query. Noted your history and understood your concerns. To have fluffy dark green colored stool after 6 months of PCOS treatment with Metformin is not known. Hence I would advise you the following: Get the stool tests done. Tests of blood for CBC, blood sugar, Insulin, thyroid and other hormonal functions. Ultrasonography of the whole abdomen. These tests will give an insight of all the problems and thus help you to get a proper diagnosis. If there is an intestinal infection, get the course of an antibiotic active against intestinal infection, probiotics and you may have a cure. Also see for the source of water and food whether this is contaminated as you are having persistent problems. I the problem is not solved then you may need further tests of CT scan of the abdomen and colonoscopy. If all the investigations are normal then intolerance to certain foods and beverages or IBS that is irritable bowel syndrome is suspected and get treated accordingly. Stress and anxiety are known to occur with PCOS, hence get treated properly to have an additional benefit.