Thanks for those links - bookmarked! Came across a few similar ones last night when Googling thyroid/IGF-1 links. Thanks also for the thyroid testing advice. I know this can be a complicated area in terms of testing and diagnosis, so it's good to have some thoughts on where to begin.
I got a letter from the hospital today saying that my IGF-1 levels were "mildly" elevated in the previous blood tests and that the endo has decided to arrange an MRI regardless of the results of the glucose tolerance test, so I guess they're taking no chances, which is reassuring. Re: other pituitary hormones, well, yes and no. The set of blood tests ordered by my GP's surgery in the spring (I'd gone in complaining of worsened hirsutism and growing dependence on those facial oil-absorbing wipes marketed at teenagers) showed high prolactin, though not elevated to the extent that would point straight to a prolactinoma. The prolactin result was the reason for the referral to endocrinology. The hospital ran a new set of blood tests, and by that time my prolactin had gone back down to normal, but was near the high end of the normal range. FSH and LH were normal. Everything else they tested for was also normal (e.g. estrogen, testosterone, etc) apart from mildly high DHEAS.
I'm glad nothing is too high for you, but that almost works against you because nothing is as clear cut.
I hope that MRI goes well and there is no sign of a pituitary adenoma. Let me know how the OGTT GH suppression test and the MRI goes. I hope they clear you of any problems and your abnormal labs were just an unexplained blip like mine.