Ah ok. Normally they start you off on the smallest doses, monitor you and increase the dose if needed. I was on 5mg carbimazole. If it's too high then yeah that would definitely send you hypo from hyper.I'm not sure what tpo is as they've never mentioned that to me? I get major anxiety when I go hyper. Only know now that I was hyper in the past because of the bouts of anxiety/depression and major weight loss. How long have you been trying if you don't mind me asking? I'm part of a Graves fb support group and part of Graves is we all are either hypo or hyper and there are so many successful pregnancy stories on there. If you have positive antibodies did they say what it was for? Like Graves, hashimotos or something? Don't worry too much. You'll find the stress is probably affecting things more. My friend was desperate to get pregnant and was ttc for 6 years. As soon as they got an ivf appt to check everything out she relaxed and found out she was pregnant a couple of days before the appt! She now has a gorgeous daughter. Everything will be absolutely fine, there are ways to keep it in check and managed. It's always the way that as soon as you stop "trying" you fall pregnant! X