Personally, I'd take an adrenal supp, I'm using Allergy Research Group's adrenal support, we've also got a Priority One supp. I'd take them if I were pregnant.
Nettle infusions are also helpful, I've read some folks have done the good lifestyle stuff, daily liver and nettles and gotten fairly good results. I feel like I need more now, but I'm also a liver-wimp.
Consider salt, I mix 1/2 tsp in water and do that 2-3x/day, the amount is pretty variable, but it makes me feel better and I think it's because it's just getting enough sodium in my body to do all the cellular work that needs to be done (minerals in/out of cells).
Do you have a really good multi? I used a crappy multi with my first child, wish I'd gotten something better. I settled on Rainbow Light 2nd time around, I bet there are good recs in Traditional Foods, maybe in one of the pregnancy boards too?
If you failed the GTT, I'd really try to make dietary changes if you can. Are you avoiding anything? (gluten/dairy, LC, anything?) Dietary changes really reduced stressed on my adrenals, for me gluten and dairy, ymmv.