You've really been through the mill, Lissie. It is a dangerous business really.
LateNightOwl- I started a thread in the Conception topic about the thyroid and infertility thing. The thing is, there are many people who are borderline hypothyroid without realising it. Your GP may have loked at your results, thought, "Bah, fine, only just underperforming", and failed to take note of the fact that your TSH might give you fertility problems. Does your GP know that you are trying to conceive?
She ought to, as even a mildly underperforming thyroid (ie one deemed "sublclinically" abnormal- ie not enough to cause symptoms) can cause the problems I outlined below. The test they do is a TSH test.
If your TSH level is anything over 2, you should ask for further investigation. If you have the symptoms of thyroid problems, but the test show you as "fine" (quote marks used b/c every person's personal levels are different, and the test is but a crude judge of how fcked someone's thyroid really is), I recommend that you ask what your levels are. Make a note of them, and use Dr Google and the various excellent websites I can provide you with to judge whether you are actually hypothyroid without exceeding the NHS's necessary fckedness level. It can still affect your fertility substantially.
Fo example, my TSH level is 5.05, but I suspect from the way I used to be that it has risen a lot, and my T4 level of 14 something is actually very low for me. GPs do not understand the endocrine system- it is all very finely balanced, and very complicated. They have little ability to distinguish between what's normal and what's not without their little books. Bottom line re thryoid is: if you have the symptoms, then you probalby are no matter what the test results throw up. Keep plugging away at them and good luck.