I'm sorry I do see where you wrote you are on glucophage. It really does help. I'm on metformin and since they're increased my dose I've lost 24 pounds. I have a problem with my weight too and would like to take off about 40 more. It's slow going.
I have PCOS too. I was diagnosed with it about 8 years ago. In dealing with my PCOS I've found that there is nothing predictable about it. At the heart of the matter, PCOS is an endocrine disorder, which basically means it messes with your hormones big time. It actually goes a LOT deeper than that and is something which I cannot fully explain because I just don't fully understand it. Nor do any of the experts so how can we? When I was tested for it my hormones actually all came back normal so I think that saying it messes with your hormones is really just putting it in layman's terms. It must be much subtler and more complex than that. It must be because no one knows the cause or how to fix the problem. Just to deal with it. I write this only to get to the point that it is complex, very complex. I've had periods that have been normal and I've had some that would start and then stop and then start. I've had some very painful, heavy periods that came only after two weeks of stopping my period. You've been regular for 18 months and that's great but the problem is that with PCOS all bets are off. I don't ovulate either on my own and chances are if you have PCOS and aren't ovulating then you're probably not going to without a little medicinal help. Look I've been given three different kinds of oral meds. for this cycle and the PCOS is putting up such a fight to keep me from ovulating that if this last round doesn't work, they're going to injectibles. In addition to the ovulation drugs their are drugs to help with the PCOS, Metformin, Glucophage, Fortamet. You may already be on one of these, I don't know but usually they will increase your dosage when you start ttc. These also help to lose weight as well as keep the cysts under control. The bottom line is you really need to see your OB/GYN and then after you've ruled out other possibilities that could be affecting you as well (like endometriosis) then you should ask about being referred to a reproductive endocronologist (fertility specialist). It may be nothing, your cycle may just be shorter this time around but with PCOS I would check because that is an entire issue all by itself. I hope I've been of some help :) Good Luck.
I'm bumping your post to the top to see if anyone has any ideas about what's going on. The only thing I can think of is that w/PCOS, one doesn't always ovulate so you need to find out if that's even going on.
congrats on the weight loss! I'm on the same journey but haven't lost near the amount of weight you have but I just got started - jen