I have pcos and had very irregular periods but when I did have them, they where about 7 days with light, med, and heavy days with bad cramps. I started taking metformin in August and now get my period every month between 24-29 days. Only they last about 3-4 days and are so light I only need a panty liner and little to no cramping. I did get a positive opk in sept and conceive but had a miscarriage in oct. I haven't had a really strong positive opk since then. Just wondering if anyone else has periods like mine and still ovulate.